'안드로이드/Android 활용'에 해당되는 글 28건

WebView webView = findViewById(R.id.webView);
webView.loadUrl("file:///android_asset/license.html"); 

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".TextToSpeechActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/layout_appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <androidx.appcompat.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </com.google.android.material.appbar.AppBarLayout>

    <com.google.android.material.textfield.TextInputLayout
        android:id="@+id/layout_textvoice"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="24dp"
        android:layout_marginTop="30dp"
        android:layout_marginEnd="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/layout_appbar">

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/et_text2voice"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="텍스트를 입력하세요"
            android:padding="10dp"></com.google.android.material.textfield.TextInputEditText>

    </com.google.android.material.textfield.TextInputLayout>

    <com.google.android.material.button.MaterialButton
        android:id="@+id/btn_speech"
        style="@style/Widget.AppCompat.Button.Borderless.Colored"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="24dp"
        android:layout_marginTop="30dp"
        android:layout_marginEnd="24dp"
        android:padding="10dp"
        android:text="음성변환"
        android:textColor="@color/colorOrangeDark"
        android:textSize="16sp"
        android:textStyle="bold"
        app:backgroundTint="@color/colorSkyBlue"
        app:cornerRadius="15dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/layout_textvoice" />

</androidx.constraintlayout.widget.ConstraintLayout> 

import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;

import java.util.Locale;

public class TextToSpeechActivity extends AppCompatActivity {
    private final String TAG = this.getClass().getSimpleName();
    Context mContext;

    private TextToSpeech textToSpeech;
    private EditText speakText;
    private Button speakBtn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_speech);
        mContext = TextToSpeechActivity.this;

        initView();
    }

    private void initView() {
        Toolbar toolbar = findViewById(R.id.toolbar);
        toolbar.setTitle("TextToSpeech");
        setSupportActionBar(toolbar);

        speakText = findViewById(R.id.et_text2voice);
        speakBtn = findViewById(R.id.btn_speech);

        textToSpeech = new TextToSpeech(getApplicationContext(), status -> {
            if (status != TextToSpeech.ERROR) {
                textToSpeech.setLanguage(Locale.KOREAN);
            }
        });

        speakBtn.setOnClickListener(v -> texttoSpeak());
    }

    private void texttoSpeak() {
        String text = speakText.getText().toString();
        if ("".equals(text)) {
            text = "Please enter some text to speak.";
            Toast.makeText(getApplicationContext(), text, Toast.LENGTH_SHORT).show();
            return;
        }

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            textToSpeech.speak(text, TextToSpeech.QUEUE_FLUSH, null, null);
        } else {
            String utteranceId = this.hashCode() + "";
            textToSpeech.speak(text, TextToSpeech.QUEUE_FLUSH, null, utteranceId);
        }
    }

    @Override
    protected void onDestroy() {
        if (textToSpeech != null) {
            textToSpeech.stop();
            textToSpeech.shutdown();
        }
        super.onDestroy();
    }

    @Override
    public void onBackPressed() {
        super.onBackPressed();
        startActivity(new Intent(mContext,SplashActivity.class));
        finish();
    }
}

private void sendEmail_default(String emailTo, String subject, String message){
    Intent emailSelectorIntent = new Intent( Intent.ACTION_SENDTO );
    emailSelectorIntent.setData( Uri.parse( "mailto:" ) );

    final Intent emailIntent = new Intent( Intent.ACTION_SEND );
    emailIntent.putExtra( Intent.EXTRA_EMAIL, new String[]{ emailTo } );
    emailIntent.putExtra(Intent.EXTRA_SUBJECT, subject);
    emailIntent.putExtra(Intent.EXTRA_TEXT, message);
    emailIntent.addFlags( Intent.FLAG_GRANT_READ_URI_PERMISSION );
    emailIntent.addFlags( Intent.FLAG_GRANT_WRITE_URI_PERMISSION );
    emailIntent.setSelector( emailSelectorIntent );

    startActivity( emailIntent );

}

private void ProfileView() {
    ImageView img_profile = findViewById(R.id.img_profile);
    TextView userNM = findViewById(R.id.tv_userNM);
    TextView mobileNO = findViewById(R.id.tv_mobileNO);

    String photoURL = Value.PhotoADDRESS + PrefsHelper.read("profileImg","") + ".jpg";
    // 사진 이미지가 존재하지 않을 수도 있으므로 존재 여부를 체크하여 존재하면 ImageView 에 표시한다.
    PhotoURLExists task = new PhotoURLExists();
    try {
        if(task.execute(photoURL).get()==true){
            Glide.with(mContext).load(photoURL).override(170, 200).into(img_profile);
        }
    } catch (ExecutionException e) {
        e.printStackTrace();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }

    userNM.setText(PrefsHelper.read("userNM",""));
    mobileNO.setText(PrefsHelper.read("mobileNO",""));
}

private class PhotoURLExists extends AsyncTask<String, Void, Boolean> {
    @Override
    protected Boolean doInBackground(String... params) {
        try {
            HttpURLConnection.setFollowRedirects(false);
            HttpURLConnection con =  (HttpURLConnection) new URL(params[0]).openConnection();
            con.setRequestMethod("HEAD");
            return (con.getResponseCode() == HttpURLConnection.HTTP_OK);
        }
        catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }
} 

implementation 'com.github.bumptech.glide:glide:4.11.0'
annotationProcessor 'com.github.bumptech.glide:compiler:4.11.0' 

Intent intent = new Intent(Intent.ACTION_VIEW);
 Uri apkUri = Uri.fromFile(outputFile);
 intent.setDataAndType(apkUri, "application/vnd.android.package-archive");
 intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
 context.startActivity(intent);

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <files-path name="files" path="." />
</paths>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.tistory.link2me.filedownload">

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />

    <application
        android:allowBackup="false"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme.NoActionBar"

        android:usesCleartextTraffic="true">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <provider
            android:name="androidx.core.content.FileProvider"
            android:authorities="${applicationId}.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths"
                tools:replace="android:resource" />
        </provider>

        <activity android:name=".DownloadAPK" />
    </application>

</manifest>

import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import com.gun0912.tedpermission.PermissionListener;
import com.gun0912.tedpermission.TedPermission;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    Context context;

    PermissionListener permissionlistener = new PermissionListener() {
        @Override
        public void onPermissionGranted() {
            MainActivity.this.Button_Click();
        }

        @Override
        public void onPermissionDenied(ArrayList<String> deniedPermissions) {
            Toast.makeText(MainActivity.this, "권한 허용을 하지 않으면 서비스를 이용할 수 없습니다.", Toast.LENGTH_SHORT).show();
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = this.getBaseContext();

        if (Build.VERSION.SDK_INT >= 23) {
            TedPermission.with(this)
                    .setPermissionListener(permissionlistener)
                    .setRationaleMessage("파일을 다운로드 하기 위해서는 접근 권한이 필요합니다")
                    .setDeniedMessage("앱에서 요구하는 권한설정이 필요합니다...\n [설정] > [권한] 에서 사용으로 활성화해주세요.")
                    .setPermissions(new String[]{"android.permission.WRITE_EXTERNAL_STORAGE", "android.permission.READ_EXTERNAL_STORAGE"})
                    .check();
        } else {
            Button_Click();
        }

    }

    private void Button_Click() {
        Button btn_dnload = (Button) findViewById(R.id.btn_image_download);
        btn_dnload.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, DownloadAPK.class);
                startActivity(intent);
            }
        });
    }
}

public class Value extends Activity {
    public static final String APKNAME = "ABC.apk"; // APK name
    public static final String IPADDRESS = "http://100.100.100.100";
}

import android.content.Context;
import android.content.Intent;
import android.media.MediaScannerConnection;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;

public class DownloadAPK extends AppCompatActivity {
    Context context;
    private File outputFile;
    ProgressBar progressBar;
    TextView textView;
    LinearLayout linearLayout;
    DownloadFileFromURL downloadFileAsyncTask;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.downloadapk_activity);
        context = this.getBaseContext();

        linearLayout = (LinearLayout) findViewById(R.id.downloadprogress_layout);
        textView = (TextView) findViewById(R.id.txtView01);
        progressBar = (ProgressBar) findViewById(R.id.progressBar);

        DownloadAPK();
    }

    private void DownloadAPK() {
        // 백그라운드 객체를 만들어 주어야 다운로드 취소가 제대로 동작됨
        downloadFileAsyncTask = new DownloadFileFromURL();
        downloadFileAsyncTask.execute(Value.IPADDRESS + "/Download.php");
    }

    class DownloadFileFromURL extends AsyncTask<String, Integer, String> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            progressBar.setProgress(0);
        }

        @Override
        protected String doInBackground(String... apkurl) {
            int count;
            int lenghtOfFile = 0;
            InputStream input = null;
            OutputStream fos = null;

            try {
                URL url = new URL(apkurl[0]);
                URLConnection connection = url.openConnection();
                connection.connect();

                lenghtOfFile = connection.getContentLength(); // 파일 크기를 가져옴

                File path = getFilesDir();
                outputFile = new File(path, Value.APKNAME);
                if (outputFile.exists()) { // 기존 파일 존재시 삭제하고 다운로드
                    outputFile.delete();
                }

                input = new BufferedInputStream(url.openStream());
                fos = new FileOutputStream(outputFile);
                byte data[] = new byte[1024];
                long total = 0;

                while ((count = input.read(data)) != -1) {
                    if (isCancelled()) {
                        input.close();
                        return String.valueOf(-1);
                    }
                    total = total + count;
                    if (lenghtOfFile > 0) { // 파일 총 크기가 0 보다 크면
                        publishProgress((int) (total * 100 / lenghtOfFile));
                    }
                    fos.write(data, 0, count); // 파일에 데이터를 기록
                }

                fos.flush();

            } catch (Exception e) {
                e.printStackTrace();
                Log.e("UpdateAPP", "Update error! " + e.getMessage());
            } finally {
                if (input != null) {
                    try {
                        input.close();
                    }
                    catch(IOException ioex) {
                    }
                }
                if (fos != null) {
                    try {
                        fos.close();
                    }
                    catch(IOException ioex) {
                    }
                }
            }
            return null;
        }

        protected void onProgressUpdate(Integer... progress) {
            super.onProgressUpdate(progress);
            // 백그라운드 작업의 진행상태를 표시하기 위해서 호출하는 메소드
            progressBar.setProgress(progress[0]);
            textView.setText("다운로드 : " + progress[0] + "%");
        }

        protected void onPostExecute(String result) {
            if (result == null) {
                progressBar.setProgress(0);
                Toast.makeText(getApplicationContext(), "다운로드 완료되었습니다.", Toast.LENGTH_LONG).show();

                System.out.println("getPackageName : "+getPackageName());
                System.out.println("APPLICATION_ID Path : "+BuildConfig.APPLICATION_ID);
                System.out.println("outputFile Path : "+ outputFile.getAbsolutePath());
                System.out.println("Fie getPath : "+ outputFile.getPath());

                // 미디어 스캐닝
                MediaScannerConnection.scanFile(getApplicationContext(), new String[]{outputFile.getAbsolutePath()}, null, new MediaScannerConnection.OnScanCompletedListener() {
                    @Override
                    public void onScanCompleted(String s, Uri uri) {

                    }
                });

                // 다운로드한 파일 실행하여 업그레이드 진행하는 코드
                if (Build.VERSION.SDK_INT >= 24) {
                    // Android Nougat ( 7.0 ) and later
                    installApk(outputFile);
                    System.out.println("SDK_INT 24 이상 ");
                } else {
                    Intent intent = new Intent(Intent.ACTION_VIEW);
                    Uri apkUri = Uri.fromFile(outputFile);
                    intent.setDataAndType(apkUri, "application/vnd.android.package-archive");
                    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    getApplicationContext().startActivity(intent);
                    System.out.println("SDK_INT 23 이하 ");
                }

            } else {
                Toast.makeText(getApplicationContext(), "다운로드 에러", Toast.LENGTH_LONG).show();
            }
        }

        protected void onCancelled() {
            // cancel메소드를 호출하면 자동으로 호출되는 메소드
            progressBar.setProgress(0);
            textView.setText("다운로드 진행 취소됨");
        }
    }

    public void installApk(File file) {
        Uri uri = FileProvider.getUriForFile(context, BuildConfig.APPLICATION_ID + ".fileprovider",file);
        Intent intent = new Intent(Intent.ACTION_VIEW);
        intent.setDataAndType(uri, "application/vnd.android.package-archive");
        intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
        context.startActivity(intent);
    }

}

    public void installApk(File file) {
        Uri fileUri = FileProvider.getUriForFile(context, context.getApplicationContext().getPackageName() + ".fileprovider",file);
        Intent intent = new Intent(Intent.ACTION_VIEW);
        intent.setDataAndType(fileUri, "application/vnd.android.package-archive");
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
        startActivity(intent);
        finish();
    } 

apply plugin: 'com.android.application'
// 코틀린 혼용 사용을 위해 추가
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.3"

    defaultConfig {
        applicationId "com.link2me.android.abc"
        minSdkVersion 23
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility = 1.8
        targetCompatibility = 1.8
    }

}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" // 코틀린 혼용 사용을 위해 추가
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'androidx.core:core-ktx:1.2.0' // 코틀린 혼용 사용을 위해 추가
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'

    implementation 'com.journeyapps:zxing-android-embedded:3.6.0'
    implementation 'gun0912.ted:tedpermission:2.0.0'
    implementation 'com.google.android.material:material:1.0.0'

    implementation 'com.naver.maps:map-sdk:3.7.1' // 네이버 지도 SDK
    implementation 'com.google.android.gms:play-services-location:17.0.0'
}

import android.content.Context;
import android.content.SharedPreferences;

public class PrefsHelper {
    private static Context mContext;
    private static SharedPreferences prefs;
    private static SharedPreferences.Editor editor;
    private static PrefsHelper prefmodule = null;
    public static final String PREF_NAME ="pref";

    public static final String BaudRate = "BaudRate";
    public static final String DataBit = "DataBit";
    public static final String StopBit = "StopBit";
    public static final String Parity ="Parity";

    public static PrefsHelper getInstance(Context context) {
        mContext = context;

        if (prefmodule == null) {
            prefmodule = new PrefsHelper();
        }
        if(prefs==null){
            prefs = mContext.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
            editor = prefs.edit();
        }
        return prefmodule;
    }

    public static String read(String key, String defValue) {
        return prefs.getString(key, defValue);
    }

    public static void write(String key, String value) {
        SharedPreferences.Editor prefsEditor = prefs.edit();
        prefsEditor.putString(key, value);
        prefsEditor.commit();
    }

    public static boolean read(String key, boolean defValue) {
        return prefs.getBoolean(key, defValue);
    }

    public static void write(String key, boolean value) {
        SharedPreferences.Editor prefsEditor = prefs.edit();
        prefsEditor.putBoolean(key, value);
        prefsEditor.commit();
    }

    public static Integer read(String key, int defValue) {
        return prefs.getInt(key, defValue);
    }

    public static void write(String key, Integer value) {
        SharedPreferences.Editor prefsEditor = prefs.edit();
        prefsEditor.putInt(key, value).commit();
    }
}

private void writePreferences(String baudRate, String dataBit, String stopBit, int parity){
    PrefsHelper.getInstance(this).write(PrefsHelper.BaudRate, baudRate);
    PrefsHelper.getInstance(this).write(PrefsHelper.DataBit, dataBit);
    PrefsHelper.getInstance(this).write(PrefsHelper.StopBit, stopBit);
    PrefsHelper.getInstance(this).write(PrefsHelper.Parity, String.valueOf(parity));
}

import android.content.Context;
import android.content.SharedPreferences;

public class PrefsHelper {
    public static final String PREFERENCE_NAME="pref";
    private Context mContext;
    private static SharedPreferences prefs;
    private static SharedPreferences.Editor prefsEditor;
    private static PrefsHelper instance;

    public static synchronized PrefsHelper init(Context context){
        if(instance == null)
            instance = new PrefsHelper(context);
        return instance;
    }

    private PrefsHelper(Context context) {
        mContext = context;
        prefs = mContext.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE );
        prefsEditor = prefs.edit();
    }

    public static String read(String key, String defValue) {
        return prefs.getString(key, defValue);
    }

    public static void write(String key, String value) {
        prefsEditor.putString(key, value);
        prefsEditor.commit();
    }

    public static Integer read(String key, int defValue) {
        return prefs.getInt(key, defValue);
    }

    public static void write(String key, Integer value) {
        prefsEditor.putInt(key, value).commit();
    }

    public static boolean read(String key, boolean defValue) {
        return prefs.getBoolean(key, defValue);
    }

    public static void write(String key, boolean value) {
        prefsEditor.putBoolean(key, value);
        prefsEditor.commit();
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">
    <!-- As the main content view, the view below consumes the entire
         space available using match_parent in both dimensions. Note that
         this child does not specify android:layout_gravity attribute. -->
    <FrameLayout
        android:id="@+id/content"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <!-- android:layout_gravity="start" tells DrawerLayout to treat
         this as a sliding drawer on the starting side, which is
         left for left-to-right locales. The navigation view extends
         the full height of the container. A
         solid background is used for contrast with the content view.
         android:fitsSystemWindows="true" tells the system to have
         DrawerLayout span the full height of the screen, including the
         system status bar on Lollipop+ versions of the plaform. -->
    <com.google.android.material.navigation.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:background="#333"
        android:fitsSystemWindows="true"
        app:menu="@menu/navigation_view_content"
        app:itemIconTint="@color/emerald_translucent"
        app:itemTextColor="@color/emerald_text"
        app:itemBackground="@color/sand_default"
        app:itemTextAppearance="@style/TextMediumStyle" />

</androidx.drawerlayout.widget.DrawerLayout>

<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <!-- 1. 콘텐츠 영역-->
    <include
        layout="@layout/content_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <!-- 2. 왼쪽 사이드 메뉴-->
    <include layout="@layout/nav_header_main" />   

</androidx.drawerlayout.widget.DrawerLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/navi_view"
    android:layout_width="280dp"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    android:background="@color/colorWhite"
    android:orientation="vertical"
    android:theme="@style/ThemeOverlay.AppCompat.Dark"
    >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#ededed"
        android:orientation="vertical"
        android:padding="10dp">

        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal">

            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:src="@drawable/img_info" />

            <ImageView
                android:id="@+id/btn_close"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="right|top"
                android:onClick="NaviItemSelected"
                android:src="@drawable/ic_close" />

        </FrameLayout>
    </LinearLayout>

</LinearLayout> 

public class MainActivity extends AppCompatActivity {
    Context context;
    DrawerLayout drawer_layout;
    ActionBarDrawerToggle toggle;
    //NavigationView navigationView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = MainActivity.this;

        drawer_layout = findViewById(R.id.drawer_layout);
        toggle = new ActionBarDrawerToggle(
                this, drawer_layout, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer_layout.addDrawerListener(toggle);
        toggle.syncState();

        // com.google.android.material.navigation.NavigationView 를 구현했을 때 처리 (구현 안해도 됨)
        //navigationView = findViewById(R.id.nav_view);
        //navigationView.setItemIconTintList(null);
        //navigationView.setNavigationItemSelectedListener(this);

        // content_main.xml 에서 지정한 버튼을 클릭하면 drawer 가 오픈되도록 함.
        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
               drawer_layout.openDrawer(GravityCompat.START);
            }
        });

    }

    // drawer 오픈된 상태에서 실행할 때 동작 이벤트 처리
    public void NaviItemSelected(View view) {
        switch (view.getId()) {
            case R.id.btn_close:
                drawer_layout.closeDrawer(Gravity.LEFT, true);
                break;
            case R.id.btn_logout:
                backPressHandler.appShutdown();
                break;
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'com.google.android.material:material:1.1.0'
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <com.google.android.material.tabs.TabLayout
        android:id="@+id/tab_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="40dp"
        app:tabTextColor="@color/colorDarkGray"
        app:tabSelectedTextColor="@color/colorWhite"
        app:layout_collapseMode="pin"
        app:tabGravity="fill"
        app:tabBackground="@drawable/tab_color_selector"
        app:layout_constraintBottom_toTopOf="@+id/vp_layout"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Monday" />

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Tuesday" />

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Wednesday" />
    </com.google.android.material.tabs.TabLayout>

    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/vp_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/tab_layout">

        <androidx.viewpager.widget.ViewPager
            android:id="@+id/viewPager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

    </androidx.constraintlayout.widget.ConstraintLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="프레그먼트1"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout> 

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="프레그먼트2"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="프레그먼트3"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;

public class Fragment1 extends Fragment {
    private View view;

    private String parameter;

    public static Fragment1 newInstance(String parameter){
        Fragment1 fragment1 = new Fragment1();
        Bundle args = new Bundle(); //Use bundle to pass data
        args.putString("parameter", parameter);
        instance.setArguments(args); //Finally set argument bundle to fragment
        return instance;
    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            parameter = getArguments().getString("parameter");
            Log.e("FragParameter", parameter);
        }
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        view = inflater.inflate(R.layout.fragment_1,container,false);
        return view;
    }

    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
    }
}

public class Fragment2 extends Fragment {
    private View view;

    public static Fragment2 newInstance(){
        Fragment2 fragment2 = new Fragment2();
        return fragment2;
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        view = inflater.inflate(R.layout.fragment_2,container,false);
        return view;
    }
} 

public class Fragment3 extends Fragment {
    private View view;

    public static Fragment3 newInstance(){
        Fragment3 fragment3 = new Fragment3();
        return fragment3;
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        view = inflater.inflate(R.layout.fragment_3,container,false);
        return view;
    }
} 

import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentPagerAdapter;

import java.util.ArrayList;
import java.util.List;

class ViewPagerAdapter extends FragmentPagerAdapter {
    private final List<Fragment> mFragmentList = new ArrayList<>();
    private final List<String> mFragTitleList = new ArrayList<>();

    public ViewPagerAdapter(FragmentManager manager) {
        super(manager);
    }

    @Override
    public Fragment getItem(int position) {
        return mFragmentList.get(position);
    }

    @Override
    public int getCount() {
        return mFragmentList.size();
    }

    public void addFrag(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragTitleList.add(title);
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return mFragTitleList.get(position);
    }
}

import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.FragmentPagerAdapter;
import androidx.viewpager.widget.ViewPager;

import android.os.Bundle;

import com.google.android.material.tabs.TabLayout;

public class MainActivity extends AppCompatActivity {
    private ViewPager viewPager;
    private ViewPagerAdapter adapter;
    private TabLayout tabLayout;

    String code;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        code = getIntent().getExtras().getString("code");
        Log.e("MainActivityCode",code);

        Fragment frag1 = new Fragment1().newInstance(code);

        viewPager = findViewById(R.id.viewPager);
        tabLayout = findViewById(R.id.tab_layout);
        adapter = new ViewPagerAdapter(getSupportFragmentManager());
        adapter.addFrag(frag1, "Web");
        adapter.addFrag(new Fragment2(), "사랑");
        adapter.addFrag(new Fragment3(), "우정");
        viewPager.setAdapter(adapter);
        tabLayout.setupWithViewPager(viewPager);
    }
}

public class FirstFragment extends Fragment {
    // Store instance variables
    private String title;
    private int page;

    // newInstance constructor for creating fragment with arguments
    public static FirstFragment newInstance(int page, String title) {
        FirstFragment fragmentFirst = new FirstFragment();
        Bundle args = new Bundle();
        args.putInt("someInt", page);
        args.putString("someTitle", title);
        fragmentFirst.setArguments(args);
        return fragmentFirst;
    }

    // Store instance variables based on arguments passed
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        page = getArguments().getInt("someInt", 0);
        title = getArguments().getString("someTitle");
    }

    // Inflate the view for the fragment based on layout XML
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_first, container, false);
        TextView tvLabel = (TextView) view.findViewById(R.id.tvLabel);
        tvLabel.setText(page + " -- " + title);
        return view;
    }
} 

public static String getDeviceId(Context context) {

    // 단말기의 ID 정보를 얻기 위해서는 READ_PHONE_STATE 권한이 필요
    String deviceId;

    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        deviceId = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ANDROID_ID);
    } else {
        final TelephonyManager mTelephony = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
        if (ActivityCompat.checkSelfPermission(context, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
            //권한 없을 경우
            if (ActivityCompat.shouldShowRequestPermissionRationale((Activity) context, Manifest.permission.READ_PHONE_STATE)) {
                // 사용자에게 해당 권한이 필요한 이유에 대해 설명
                Toast.makeText(context, "앱 실행을 위해서는 전화 관리 권한을 설정해야 합니다.", Toast.LENGTH_SHORT).show();
            }
            // 최초로 권한을 요청하는 경우
            ActivityCompat.requestPermissions((Activity) context, new String[]{Manifest.permission.READ_PHONE_STATE} , 2);
            return null;
        } else {
            Log.v("TAG","Permission is granted");
            if (mTelephony.getDeviceId() != null) {
                deviceId = mTelephony.getDeviceId();
            } else {
                deviceId = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ANDROID_ID);
            }
        }
    }
    return deviceId;
}

@Override
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
    switch (requestCode) {
        case 2: {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(getApplicationContext(), "Permission granted", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(getApplicationContext(), "Permission denied", Toast.LENGTH_SHORT).show();
            }
            return;
        }
    }
} 

//TelephonyManager tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
String uID = Settings.Secure.getString(getApplicationContext().getContentResolver(), Settings.Secure.ANDROID_ID);

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <Button
        android:id="@+id/btn_fileread"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:text="File Read"
        android:textAllCaps="false"/>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/linear_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="#ffffff">

    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:id="@+id/popupTitle"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="3"
            android:gravity="center"
            android:text="읽은 파일 미리보기"
            android:textSize="18sp"
            android:textStyle="bold"
            android:background="@color/colorPrimary"/>

        <TextView
            android:id="@+id/popupSaveBtn"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="적용"
            android:textSize="18sp"
            android:textStyle="bold"
            android:background="#B5FFD5"/>

        <TextView
            android:id="@+id/popupCancelBtn"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="취소"
            android:textSize="18sp"
            android:textStyle="bold"
            android:background="#FFFF00"/>

    </LinearLayout>

    <ScrollView
        android:id="@+id/popupScrollView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#000000">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <TextView
                android:id="@+id/popupText"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dp"
                android:ellipsize="start"
                android:gravity="left"
                android:textColor="#FFFFFF"
                android:textStyle="bold" />
        </LinearLayout>
    </ScrollView>

</LinearLayout>

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    private static final String TAG = "MainActivity";
    Context mContext;

    Button popup_alert;
    String select_filePath;
    ScrollView pScrollView;
    View popupView;

    private static final int READ_REQUEST_CODE = 42;

    protected View mPopupView; // 팝업 뷰

    private void initView() {
       // 1. 특정 폴더에 있는 파일 읽어서 미리보기 화면에 보여주기
        popup_alert = findViewById(R.id.btn_fileread);
        popup_alert.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.btn_fileread:
                popupView = view;
                showFileChooser();
                break;
        }
    }

    private void showFileChooser() {
        Intent intent;
        if (android.os.Build.MANUFACTURER.equalsIgnoreCase("samsung")) {
            intent = new Intent("com.sec.android.app.myfiles.PICK_DATA");
            intent.putExtra("CONTENT_TYPE", "*/*");
            intent.addCategory(Intent.CATEGORY_DEFAULT);
        } else {

            String[] mimeTypes =
                    {"application/msword", "application/vnd.openxmlformats-officedocument.wordprocessingml.document", // .doc & .docx
                            "application/vnd.ms-powerpoint", "application/vnd.openxmlformats-officedocument.presentationml.presentation", // .ppt & .pptx
                            "application/vnd.ms-excel", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", // .xls & .xlsx
                            "text/plain",
                            "application/pdf",
                            "application/zip", "application/vnd.android.package-archive"};

            intent = new Intent(Intent.ACTION_GET_CONTENT); // or ACTION_OPEN_DOCUMENT
            intent.setType("*/*");
            intent.putExtra(Intent.EXTRA_MIME_TYPES, mimeTypes);
            intent.addCategory(Intent.CATEGORY_OPENABLE);
            intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true);
        }

        try {
            startActivityForResult(Intent.createChooser(intent, "Select a File"), READ_REQUEST_CODE);
        } catch (android.content.ActivityNotFoundException ex) {
            Toast.makeText(this, "Please install a File Manager.",Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode) {
            case READ_REQUEST_CODE:
                if (resultCode == RESULT_OK) {
                    // Get the Uri of the selected file
                    Uri uri = data.getData();
                    select_filePath = getRealPathFromURI(uri); // 이 함수를 다른 걸로 대체하는게 공부
                    Log.e(TAG, "file_path = " + select_filePath);
                    if(select_filePath != null){
                        mPopupWindowShow(readFile(select_filePath));
                    }
                }
                break;
        }
        super.onActivityResult(requestCode, resultCode, data);
    }

    private String getRealPathFromURI(Uri uri) {
        String filePath = "";
        filePath = uri.getPath();
        //경로에 /storage가 들어가면 real file path로 판단
        if (filePath.startsWith("/storage"))
            return filePath;

        String wholeID = DocumentsContract.getDocumentId(uri);

        //wholeID는 파일명이 abc.zip이라면 /document/B5D7-1CE9:abc.zip와 같다.
        // Split at colon, use second item in the array
        String id = wholeID.split(":")[1];

        Log.e(TAG, "id = " + id);

        String[] column = { MediaStore.Files.FileColumns.DATA };

        //파일의 이름을 통해 where 조건식을 만든다.
        String sel = MediaStore.Files.FileColumns.DATA + " LIKE '%" + id + "%'";

        //External storage에 있는 파일의 DB를 접근하는 방법이다.
        Cursor cursor = getContentResolver().query(MediaStore.Files.getContentUri("external"),
                column, sel, null, null);

        int columnIndex = cursor.getColumnIndex(column[0]);

        if (cursor.moveToFirst()) {
            filePath = cursor.getString(columnIndex);
        }
        cursor.close();
        return filePath;
    }

    private String readFile(String filepath) {
        File fileEvents = new File(filepath);
        StringBuilder text = new StringBuilder();
        try {
            BufferedReader br = new BufferedReader(new FileReader(fileEvents));
            String line;
            while ((line = br.readLine()) != null) {
                text.append(line);
                text.append('\n');
            }
            br.close();
        } catch (IOException e) { }
        String result = text.toString();
        return result;
    }

    public void mPopupWindowShow(String url) {
        Display display = ((WindowManager)getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
        Point point = new Point();
        display.getSize(point);
        int height = (int) (point.y * 0.8);
        int width = (int) (point.x * 0.9); // Display 사이즈의 90%

        // inflate the layout of the popup window
        LayoutInflater inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
        LinearLayout layout = (LinearLayout) inflater.inflate(R.layout.popup_window,null);
        mPopupView = layout.findViewById(R.id.linear_layout);

        TextView popupTitle = layout.findViewById(R.id.popupTitle);
        popupTitle.setText("내용 미리보기");
        TextView popupSave = layout.findViewById(R.id.popupSaveBtn);

        TextView popupCancel = layout.findViewById(R.id.popupCancelBtn);

        pScrollView = layout.findViewById(R.id.popupScrollView);
        TextView popupContent = layout.findViewById(R.id.popupText);
        popupContent.setText(url);

        pScrollView.setVerticalScrollBarEnabled(true); // 수직방향 스크롤바 사용 가능하도록 설정
        popupContent.setMovementMethod(new ScrollingMovementMethod());
        popupContent.setTextSize(12);

        // create the popup window
        boolean focusable = true; // lets taps outside the popup also dismiss it
        final PopupWindow popupWindow = new PopupWindow(mPopupView, width, height, focusable);

        popupWindow.showAtLocation(popupView, Gravity.BOTTOM, 0, 0); // Parent View 로부터의 위치

        popupSave.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(mContext, "적용을 시작합니다.", Toast.LENGTH_SHORT).show();
            }
        });

        popupCancel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (popupWindow != null && popupWindow.isShowing()){
                    popupWindow.dismiss();
                }
            }
        });
    }

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/btn_servicestart"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center_vertical"
        android:layout_gravity="center"
        android:text="서비스 시작"
        android:textSize="14sp"
        android:textAllCaps="false"
        android:layout_marginTop="30dp"/>

    <Button
        android:id="@+id/btn_servicestop"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="서비스 종료"
        android:layout_gravity="center"
        android:gravity="center"
        android:textSize="14sp"
        android:textAllCaps="false"
        android:layout_marginTop="20dp"/>

    <Button
        android:id="@+id/btn_bindservice"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="바인드 값"
        android:layout_gravity="center"
        android:gravity="center"
        android:textSize="14sp"
        android:textAllCaps="false"
        android:layout_marginTop="20dp"/>

</LinearLayout>

import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;

public class MyService extends Service {
    private static final String TAG = MyService.class.getSimpleName();
    private Context context;
    private int mCount = 0;
    private Thread mThread;
    public static boolean SERVICE_CONNECTED = false;

    public MyService() {
    }

    private IBinder mBinder = new MyBinder();
    public class MyBinder extends Binder {
        public MyService getService(){
            Log.e(TAG, "MyService MyBinder return.");
            return MyService.this;  // 서비스 객체를 리턴
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        Log.e(TAG, "MyService IBinder onBind");
        // Service 객체와 (화면단 Activity 사이에서) 데이터를 주고받을 때 사용하는 메서드
        // Activity에서 bindService() 를 실행하면 호출됨
        // 데이터를 전달할 필요가 없으면 return null;
        return mBinder; // 리턴한 mBinder 객체는 서비스와 클라이언트 사이의 인터페이스를 정의한다.
    }

    public int getCount(){
        return mCount;
    }

    @Override
    public void onCreate() {
        Log.e(TAG, "MyService Started");
        this.context = this;
        MyService.SERVICE_CONNECTED = true;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.e(TAG, "MyService onStartCommand startID === "+startId); // 계속 증가되는 값
        if(mThread == null){
            mThread = new Thread("My Thread"){
                @Override
                public void run() {
                    while (!Thread.currentThread().isInterrupted()){
                        try {
                            mCount++;
                            Thread.sleep(1000);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                            this.interrupt();
                        }
                        Log.e("My Thread", "서비스 동작 중 " + mCount);
                    }
                }
            };
            mThread.start();
        }
        return START_STICKY;
    }

    @Override
    public void onDestroy() {
        Log.e(TAG,"MyService onDestroy");
        super.onDestroy();
        if(mThread != null && mThread.isAlive() ){
            mThread.interrupt();
            mThread = null;
            mCount = 0;
        }
        SERVICE_CONNECTED = false;
    }
}

import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import java.util.Set;

public class MainActivity extends AppCompatActivity {
    private static final String TAG = MainActivity.class.getSimpleName();
    Context mContext;
    private Button btnServiceStart;
    private Button btnServiceStop;
    private Button btnBindService;

    private MyService myService;
    private boolean mBound = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mContext = MainActivity.this;

        btnServiceStart = findViewById(R.id.btn_servicestart);
        btnServiceStop = findViewById(R.id.btn_servicestop);
        btnBindService = findViewById(R.id.btn_bindservice);

        btnServiceStart.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(mContext, "서비스를 시작합니다.", Toast.LENGTH_SHORT).show();
                Intent intent = new Intent(mContext,MyService.class);
                startService(intent);
            }
        });

        btnServiceStop.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(mContext, "서비스를 종료합니다.", Toast.LENGTH_SHORT).show();
                Log.e(TAG,"MainActivity ServiceStop Button Clicked.");
                if(mBound){
                    unbindService(mConnection);
                    mBound = false;
                }
                stopService(new Intent(mContext,MyService.class));
            }
        });

        btnBindService.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(mBound){
                    Toast.makeText(mContext, "카운팅 : " + myService.getCount(), Toast.LENGTH_SHORT).show();
                }
            }
        });
    }

    @Override
    protected void onDestroy() {
        Log.e(TAG,"MainActivity onDestroy");
        if(mBound){
            unbindService(mConnection);
            mBound = false;
        }
        stopService(new Intent(this,MyService.class));
        super.onDestroy();
    }

    @Override
    protected void onStart() {
        super.onStart();
        Intent intent = new Intent(this,MyService.class);
        bindService(intent,mConnection,BIND_AUTO_CREATE); // startService 버튼 클릭시 시작
//        startService(MyService.class, mConnection,null); // Activity 시작시 startService 자동 실행
    }

    private ServiceConnection mConnection = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            MyService.MyBinder binder = (MyService.MyBinder) service;
            myService = binder.getService();
            mBound = true;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            // 예기치 않은 종료(안드로이드 OS에 의한 종료)

            mBound = false;
        }
    };

    private void startService(Class<?> service, ServiceConnection serviceConnection, Bundle extras) {
        // onStart 메소드에서 서비스 자동 실행 처리할 목적
        if (!MyService.SERVICE_CONNECTED) {
            Intent startService = new Intent(this, service);
            if (extras != null && !extras.isEmpty()) {
                Set<String> keys = extras.keySet();
                for (String key : keys) {
                    String extra = extras.getString(key);
                    startService.putExtra(key, extra);
                }
            }
            startService(startService);
        }
        Intent bindingIntent = new Intent(this, service);
        bindService(bindingIntent, serviceConnection, Context.BIND_AUTO_CREATE);
    }
}

android {
    compileSdkVersion 28

   // 중간 생략

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'gun0912.ted:tedpermission:2.0.0'
    implementation 'androidx.multidex:multidex:2.0.0' // minSdkVersion 이 21 이하인 경우 사용
    implementation 'com.jcraft:jsch:0.1.55'
    implementation 'org.bouncycastle:bcprov-jdk16:1.46'
}

    public void writeToOutput(final String command) {
        if (mDataOutputStream != null) {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        mDataOutputStream.writeBytes(command + "\r\n");
                        mDataOutputStream.flush();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).start();

        }
    }

   public void openShell(final Session session, Handler handler, EditText editText) throws JSchException, IOException {
        Log.e(TAG, "openShell start!");
        if (session == null) throw new NullPointerException("Session cannot be null!");
        if (!session.isConnected()) throw new IllegalStateException("Session must be connected.");
        final Handler myHandler = handler;
        final EditText myEditText = editText;
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    mChannel = session.openChannel("shell");
                    mChannel.connect();
                    try {
                        mBufferedReader = new BufferedReader(new InputStreamReader(mChannel.getInputStream()));
                        mDataOutputStream = new DataOutputStream(mChannel.getOutputStream());
                    } catch (IOException e) {
                        e.printStackTrace();
                    }

                } catch (JSchException e) {
                    e.printStackTrace();
                }

                try {
                    String line;
                    while (true) {
                        while ((line = mBufferedReader.readLine()) != null) {
                            final String result = line;
                            if (mSshText == null) mSshText = result;
                            Log.e(TAG, "result : " + result);
                            myHandler.post(new Runnable() {
                                public void run() {
                                    synchronized (myEditText) {
                                        ((SshEditText)myEditText).setPrompt(result); //set the prompt to be the current line, so eventually it will be the last line.
                                        myEditText.setText(myEditText.getText().toString() + "\r\n" + result + "\r\n"+fetchPrompt(result));
                                        Log.e(TAG, "LINE : " + result);
                                    }
                                }
                            });
                        }

                    }
                } catch (Exception e) {
                    Log.e(TAG, " Exception " + e.getMessage() + "." + e.getCause() + "," + e.getClass().toString());
                }
            }
        }).start();
    }
 

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28

    defaultConfig {
        applicationId "com.link2me.android.wakemeup"
        minSdkVersion 19
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.link2me.android.wakemeup">

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/icon_watch"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <receiver android:name=".AlarmReceiver" />

        <service
            android:name=".RingtoneService"
            android:enabled="true"></service>

    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical"
    android:gravity="top">

    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <TimePicker
            android:id="@+id/time_picker"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center">

        <Button
            android:layout_width="60dp"
            android:layout_height="50dp"
            android:id="@+id/btn_alarmStart"
            android:text="시작"/>

        <Button
            android:layout_width="60dp"
            android:layout_height="50dp"
            android:id="@+id/btn_alarmFinish"
            android:text="종료" />

    </LinearLayout>

    <TextView
        android:id="@+id/tv_alarmON"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:layout_marginTop="30dp"
        android:text="알람 예정 시간"
        android:textSize="14dp"
        android:textColor="@color/colorAccent"/>

</LinearLayout>

package com.link2me.android.wakemeup;

import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Build;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.TimePicker;
import android.widget.Toast;

import androidx.annotation.RequiresApi;
import androidx.appcompat.app.AppCompatActivity;

import com.link2me.android.common.BackPressHandler;

import java.util.Calendar;

public class MainActivity extends AppCompatActivity {
    private static final String TAG = MainActivity.class.getSimpleName();
    Context mContext;
    TextView textView;
    TimePicker alarm_timepicker;
    AlarmManager alarm_manager;
    String am_pm;
    int getHourTimePicker = 0;
    int getMinuteTimePicker = 0;

    Intent alarmIntent;
    PendingIntent pendingIntent;
    private static final int REQUEST_CODE = 1111;
    SharedPreferences pref;

    private BackPressHandler backPressHandler;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mContext = MainActivity.this;
        backPressHandler = new BackPressHandler(this); // 뒤로 가기 버튼 이벤트

        textView = findViewById(R.id.tv_alarmON);
        textView.setText("");

        // 알람매니저 설정
        alarm_manager = (AlarmManager) mContext.getSystemService(ALARM_SERVICE);
        // 알람매니저가 유용한 이유는, Alarm이 한번 등록되면 어플리케이션의 생명주기와 관계없이
        // 어플리케이션이 종료되어있는 경우에도 지정해놓은 operation에 대해 어김없이 실행할 수 있다는 것

        // 타임피커 설정
        alarm_timepicker = findViewById(R.id.time_picker);
        alarm_timepicker.setIs24HourView(true);

        // 알람 Receiver 인텐트 생성
        alarmIntent = new Intent(mContext, AlarmReceiver.class);

        // Button Alarm ON
        Button alarm_on = findViewById(R.id.btn_alarmStart);
        alarm_on.setOnClickListener(new View.OnClickListener() {
            @RequiresApi(api = Build.VERSION_CODES.M)
            @Override
            public void onClick(View v) {
                setAlarm(mContext);
            }
        });

        Button alarm_off = findViewById(R.id.btn_alarmFinish);
        alarm_off.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                releaseAlarm(mContext);
            }
        });
    }

    private void setAlarm(Context context){
        // Calendar 객체 생성
        final Calendar calendar = Calendar.getInstance();

        // calendar에 시간 셋팅
        if (Build.VERSION.SDK_INT < 23) {
            // 시간 가져옴
            getHourTimePicker = alarm_timepicker.getCurrentHour();
            getMinuteTimePicker = alarm_timepicker.getCurrentMinute();
        } else {
            // 시간 가져옴
            getHourTimePicker = alarm_timepicker.getHour();
            getMinuteTimePicker = alarm_timepicker.getMinute();
        }

        // 현재 지정된 시간으로 알람 시간 설정
        calendar.setTimeInMillis(System.currentTimeMillis());
        calendar.set(Calendar.HOUR_OF_DAY, getHourTimePicker);
        calendar.set(Calendar.MINUTE, getMinuteTimePicker);
        calendar.set(Calendar.SECOND, 0);

        pref = getSharedPreferences("pref", Activity.MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putInt("set_hour", getHourTimePicker);
        editor.putInt("set_min", getMinuteTimePicker);
        editor.putString("state", "ALARM_ON");
        editor.commit();

        // reveiver에 string 값 넘겨주기
        alarmIntent.putExtra("state","ALARM_ON");

        // receiver를 동작하게 하기 위해 PendingIntent의 인스턴스를 생성할 때, getBroadcast 라는 메소드를 사용
        // requestCode는 나중에 Alarm을 해제 할때 어떤 Alarm을 해제할지를 식별하는 코드
        pendingIntent = PendingIntent.getBroadcast(mContext,REQUEST_CODE,alarmIntent,PendingIntent.FLAG_UPDATE_CURRENT);

        long currentTime = System.currentTimeMillis(); // 현재 시간
        //long triggerTime = SystemClock.elapsedRealtime() + 1000*60;
        long triggerTime = calendar.getTimeInMillis(); // 알람을 울릴 시간
        long interval = 1000 * 60 * 60  * 24; // 하루의 시간

        while(currentTime > triggerTime){ // 현재 시간보다 작다면
            triggerTime += interval; // 다음날 울리도록 처리
        }
        Log.e(TAG, "set Alarm : " + getHourTimePicker + " 시 " + getMinuteTimePicker + "분");

        // 알림 세팅 : AlarmManager 인스턴스에서 set 메소드를 실행시키는 것은 단발성 Alarm을 생성하는 것
        // RTC_WAKEUP : UTC 표준시간을 기준으로 하는 명시적인 시간에 intent를 발생, 장치를 깨움
        if (Build.VERSION.SDK_INT < 23) {
            if (Build.VERSION.SDK_INT >= 19) {
                alarm_manager.setExact(AlarmManager.RTC_WAKEUP, triggerTime, pendingIntent);
            } else {
                // 알람셋팅
                alarm_manager.set(AlarmManager.RTC_WAKEUP, triggerTime, pendingIntent);
            }
        } else {  // 23 이상
            alarm_manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, triggerTime, pendingIntent);
            //alarm_manager.set(AlarmManager.RTC_WAKEUP, triggerTime,pendingIntent);
            //알람 매니저를 통한 반복알람 설정
            //alarm_manager.setRepeating(AlarmManager.RTC, triggerTime, interval, pendingIntent);
            // interval : 다음 알람이 울리기까지의 시간
        }

        // Unable to find keycodes for AM and PM.
        if(getHourTimePicker > 12){
            am_pm = "오후";
            getHourTimePicker = getHourTimePicker - 12;
        } else {
            am_pm ="오전";
        }
        textView.setText("알람 예정 시간 : "+ am_pm +" "+ getHourTimePicker + "시 " + getMinuteTimePicker + "분");
    }

    public void releaseAlarm(Context context)  {
        Log.e(TAG, "unregisterAlarm");

        pref = getSharedPreferences("pref", Activity.MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putString("state", "ALARM_OFF");
        editor.commit();

        // 알람매니저 취소
        alarm_manager.cancel(pendingIntent);
        alarmIntent.putExtra("state","ALARM_OFF");

        // 알람 취소
        sendBroadcast(alarmIntent);

        Toast.makeText(MainActivity.this,"Alarm 종료",Toast.LENGTH_SHORT).show();
        textView.setText("");
    }

    @Override
    public void onBackPressed() {
        backPressHandler.onBackPressed();
    }

}

package com.link2me.android.wakemeup;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.media.MediaPlayer;
import android.os.PowerManager;
import android.util.Log;

public class AlarmReceiver extends BroadcastReceiver{
    private static final String TAG = AlarmReceiver.class.getSimpleName();
    Context mContext;

    PowerManager powerManager;
    private static PowerManager.WakeLock wakeLock;
    SharedPreferences pref;
    String get_state;
    private MediaPlayer mediaPlayer;

    @Override
    public void onReceive(Context context, Intent intent) {
        mContext = context;
        pref = context.getSharedPreferences("pref", Activity.MODE_PRIVATE);
        get_state = pref.getString("state","");
        Log.e(TAG, "Alarm state : " + get_state);

        AlarmReceiverChk(context, intent);
    }

    private void AlarmReceiverChk(final Context context, final Intent intent){
        Log.d(TAG, "Alarm Receiver started!");
        switch (get_state){
            case "ALARM_ON":
                acquireCPUWakeLock(context, intent);
                // RingtoneService 서비스 intent 생성
                Intent serviceIntent = new Intent(mContext, RingtoneService.class);
                serviceIntent.putExtra("state", get_state);
                if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O){
                    context.startForegroundService(serviceIntent);
                } else {
                    context.startService(serviceIntent);
                }
                break;
            case "ALARM_OFF": // stopService 가 동작하지 않아서 startService 로 처리하고 나서....
                releaseCpuLock();
                Intent stopIntent = new Intent(context, RingtoneService.class);
                stopIntent.putExtra("state", get_state);
                if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O){
                    context.startForegroundService(stopIntent);
                } else {
                    context.startService(stopIntent);
                }
                break;
        }
    }

    @SuppressLint("InvalidWakeLockTag")
    private void acquireCPUWakeLock(Context context, Intent intent) {
        // 잠든 화면 깨우기
        if (wakeLock != null) {
            return;
        }
        powerManager = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
        wakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP
                | PowerManager.ON_AFTER_RELEASE, "WAKELOCK");
        wakeLock.acquire();
        Log.e("PushWakeLock", "Acquire cpu WakeLock = " + wakeLock);
    }

    private void releaseCpuLock() {
        Log.e("PushWakeLock", "Releasing cpu WakeLock = " + wakeLock);

        if (wakeLock != null) {
            wakeLock.release();
            wakeLock = null;
        }
    }
}

package com.link2me.android.wakemeup;

import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.media.MediaPlayer;
import android.os.Build;
import android.os.IBinder;
import android.util.Log;

import androidx.annotation.Nullable;
import androidx.core.app.NotificationCompat;


public class RingtoneService extends Service{
    private static final String TAG = RingtoneService.class.getSimpleName();
    MediaPlayer mediaPlayer;

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        // Service 객체와 (화면단 Activity 사이에서) 데이터를 주고받을 때 사용하는 메서드
        // 데이터를 전달할 필요가 없으면 return null;
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        // 서비스에서 가장 먼저 호출됨(최초에 한번만)
        Log.i(TAG, "RingtoneService Started");

        NotificationHelper notificationHelper = new NotificationHelper(getApplicationContext());
        notificationHelper.createNotification("알람시작","알람음이 재생됩니다.");

        // https://link2me.tistory.com/1514 에 첨부된 파일 받아서 수정 사용하면 해결됨

    }


    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.i(TAG, "onStartCommand startID === "+startId); // 계속 증가되는 값

        String getState = intent.getExtras().getString("state");
        Log.e("TAG","onStartCommand getState : " + getState);

        switch (getState) {
            case "ALARM_ON":
                if(mediaPlayer == null){
                    mediaPlayer = MediaPlayer.create(this,R.raw.ouu);
                    mediaPlayer.start();

                    mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
                        @Override
                        public void onCompletion(MediaPlayer mp) {
                            Log.e(TAG, "mediaPlayer Completed!");
                            mediaPlayer.stop();
                            mediaPlayer.reset();
                            mediaPlayer.release();
                        }
                    });
                }
                break;
            case "ALARM_OFF":
                Log.e(TAG, "onStartCommand Stoped!");

                if (mediaPlayer != null) {
                    if(mediaPlayer.isPlaying() == true){
                        mediaPlayer.stop();
                        mediaPlayer.release(); // 자원 반환
                        mediaPlayer = null;
                    }
                }
                stopSelf();
                break;
            default:
                break;
        }
        return START_NOT_STICKY;
    }

    @Override
    public void onDestroy() {
        Log.i(TAG, "Action Service Ended");
        super.onDestroy();
        stopForeground(true);
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/tv_battery"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:text="배터리 잔량"
        />

</LinearLayout>

import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.Bundle;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TextView textView = findViewById(R.id.tv_battery);

        // 안드로이드의 BatteryManager가 고정 인텐트를 사용하고 있기 때문에
        // 실제 BroadcastReceiver를 등록 할 필요가 없다.

        IntentFilter ifilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
        Intent batteryStatus = registerReceiver(null, ifilter);

        int level = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
        int scale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);

        float batteryPct = level / (float)scale;
        String value = String.valueOf((int)(batteryPct*100));

        textView.setText("Battery Level Remaining: " + value + "%");
    }
}

apply plugin: 'com.android.application'

android {
    compileSdkVersion 27

    defaultConfig {
        applicationId "com.tistory.android.excel"
        minSdkVersion 19
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }

}

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.android.support:support-v4:27.1.1'
    implementation 'com.android.support:recyclerview-v7:27.1.1' // ListView 개선 버전
    implementation 'com.android.support:cardview-v7:27.1.1'
    implementation 'com.android.support:design:27.1.1'
    implementation 'gun0912.ted:tedpermission:2.0.0'
    implementation 'com.android.volley:volley:1.1.0'
    implementation 'com.github.bumptech.glide:glide:3.8.0' // 이미지 라이브러리
    implementation files('libs/poi-4.0.1.jar')
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.tistory.android.excel">

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="${applicationId}.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths"
                tools:replace="android:resource" />
        </provider>

    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="excel" path="." />
</paths>

if (Build.VERSION.SDK_INT >= 24) { // Android Nougat ( 7.0 ) and later
    Uri uri = FileProvider.getUriForFile(context, BuildConfig.APPLICATION_ID + ".fileprovider",xlsFile);
    Intent intent = new Intent(Intent.ACTION_SEND);
    intent.setDataAndType(uri, "application/excel");
    intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
    intent.putExtra(Intent.EXTRA_STREAM,uri);
    startActivity(Intent.createChooser(intent,"엑셀 내보내기"));
} else {
    Uri uri = Uri.fromFile(xlsFile);
    Intent intent = new Intent(Intent.ACTION_SEND);
    intent.setType("application/excel");
    intent.putExtra(Intent.EXTRA_STREAM,uri);
    startActivity(Intent.createChooser(intent,"엑셀 내보내기"));
}

// 미디어 스캐닝 (폴더내에 생성된 파일 보이도록 하는 코드)
MediaScannerConnection.scanFile(getApplicationContext(), new String[]{xlsFile.getAbsolutePath()}, null, new MediaScannerConnection.OnScanCompletedListener() {
    @Override
    public void onScanCompleted(String s, Uri uri) {
    }
}); 

package com.tistory.android.excel;

import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.media.MediaScannerConnection;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.support.design.widget.FloatingActionButton;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Toast;

import com.gun0912.tedpermission.PermissionListener;
import com.gun0912.tedpermission.TedPermission;
import com.tistory.android.common.BackPressHandler;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    Context context;
    ArrayList<String> aryName = new ArrayList<>();
    ArrayList<String> aryAge = new ArrayList<>();

    String exportFolderName = "/DCIM/Excel";
    String outputFileName = "test.xls";
    File xlsFile;

    private BackPressHandler backPressHandler;

    PermissionListener permissionlistener = new PermissionListener() {
        @Override
        public void onPermissionGranted() {
            initView();
        }

        @Override
        public void onPermissionDenied(ArrayList<String> deniedPermissions) {
            Toast.makeText(MainActivity.this, "권한 허용을 하지 않으면 서비스를 이용할 수 없습니다.", Toast.LENGTH_SHORT).show();
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = this.getBaseContext();
        backPressHandler = new BackPressHandler(this); // 뒤로 가기 버튼 이벤트

        // 네트워크 연결상태 체크
        if (NetworkConnection() == false) NotConnected_showAlert();
        checkPermissions();
    }

    private void checkPermissions() {
        if (Build.VERSION.SDK_INT >= 23) { // 마시멜로(안드로이드 6.0) 이상 권한 체크
            TedPermission.with(context)
                    .setPermissionListener(permissionlistener)
                    .setRationaleMessage("앱을 이용하기 위해서는 접근 권한이 필요합니다")
                    .setDeniedMessage("앱에서 요구하는 권한설정이 필요합니다...\n [설정] > [권한] 에서 사용으로 활성화해주세요.")
                    .setPermissions(new String[]{
                            //android.Manifest.permission.READ_PHONE_STATE,
                            //android.Manifest.permission.CALL_PHONE,  // 전화걸기 및 관리
                            //android.Manifest.permission.WRITE_CONTACTS, // 주소록 액세스 권한
                            android.Manifest.permission.READ_EXTERNAL_STORAGE,
                            android.Manifest.permission.WRITE_EXTERNAL_STORAGE // 기기, 사진, 미디어, 파일 엑세스 권한
                            //android.Manifest.permission.RECEIVE_SMS //, // 문자 수신
                            //android.Manifest.permission.CAMERA
                    })
                    .check();

        } else {
            initView();
        }
    }

    private void initView() {
        initData(); // 읽어온 데이터라고 가정하고 데이터 생성

        FloatingActionButton fab =  findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                saveExcel();
            }
        });
    }

    private void initData(){ // 엑셀에 저장여부만 확인 목적으로 간단하게 추가하는 코드로 작성
        aryName.add("강감찬"); aryAge.add("23");
        aryName.add("이순신"); aryAge.add("57");
        aryName.add("홍길동"); aryAge.add("34");
        aryName.add("이방원"); aryAge.add("53");
        aryName.add("고주몽"); aryAge.add("73");
        aryName.add("유관순"); aryAge.add("68");
    }

    private void saveExcel(){
        Workbook workbook = new HSSFWorkbook();
        Sheet sheet = workbook.createSheet(); // 새로운 시트 생성
        Row row = sheet.createRow(0); // 새로운 행 생성
        Cell cell;

        cell = row.createCell(0); // 1번 셀 생성
        cell.setCellValue("이름"); // 1번 셀 값 입력

        cell = row.createCell(1); // 2번 셀 생성
        cell.setCellValue("나이"); // 2번 셀 값 입력

        cell = row.createCell(2); // 3번 셀 생성
        cell.setCellValue("전화번호"); // 3번 셀 값 입력

        for(int i = 0; i < aryName.size() ; i++){ // 데이터 엑셀에 입력
            row = sheet.createRow(i+1);

            cell = row.createCell(0);
            cell.setCellValue(aryName.get(i));

            cell = row.createCell(1);
            cell.setCellValue(aryAge.get(i));
        }

        // 저장할 폴더 및 파일명
        File xlsPath = new File(Environment.getExternalStorageDirectory() + exportFolderName);
        if (! xlsPath.exists())
            xlsPath.mkdirs(); // 디렉토리가 없으면 생성
        xlsFile = new File(xlsPath, outputFileName);
        if (xlsFile.exists()) { // 기존 파일 존재시 삭제
            xlsFile.delete();
        }

        try{
            FileOutputStream os = new FileOutputStream(xlsFile);
            workbook.write(os); // 지정된 외부 저장소에 엑셀 파일 생성
        }catch (IOException e){
            e.printStackTrace();
        }
        Toast.makeText(getApplicationContext(),xlsFile.getAbsolutePath()+"에 저장되었습니다",Toast.LENGTH_SHORT).show();

        if (Build.VERSION.SDK_INT >= 24) { // Android Nougat ( 7.0 ) and later
            Uri uri = FileProvider.getUriForFile(context, BuildConfig.APPLICATION_ID + ".fileprovider",xlsFile);
            Intent intent = new Intent(Intent.ACTION_SEND);
            intent.setDataAndType(uri, "application/excel");
            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            intent.putExtra(Intent.EXTRA_STREAM,uri);
            startActivity(Intent.createChooser(intent,"엑셀 내보내기"));
        } else {
            Uri uri = Uri.fromFile(xlsFile);
            Intent intent = new Intent(Intent.ACTION_SEND);
            intent.setType("application/excel");
            intent.putExtra(Intent.EXTRA_STREAM,uri);
            startActivity(Intent.createChooser(intent,"엑셀 내보내기"));
        }

        // 미디어 스캐닝
        MediaScannerConnection.scanFile(getApplicationContext(), new String[]{xlsFile.getAbsolutePath()}, null, new MediaScannerConnection.OnScanCompletedListener() {
            @Override
            public void onScanCompleted(String s, Uri uri) {
            }
        });


    }

    private void NotConnected_showAlert() {
        AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
        builder.setTitle("네트워크 연결 오류");
        builder.setMessage("사용 가능한 무선네트워크가 없습니다.\n" + "먼저 무선네트워크 연결상태를 확인해 주세요.")
                .setCancelable(false)
                .setPositiveButton("확인", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        finish(); // exit
                        //application 프로세스를 강제 종료
                        android.os.Process.killProcess(android.os.Process.myPid());
                    }
                });
        AlertDialog alert = builder.create();
        alert.show();
    }

    private boolean NetworkConnection() {
        int[] networkTypes = {ConnectivityManager.TYPE_MOBILE, ConnectivityManager.TYPE_WIFI};
        try {
            ConnectivityManager manager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
            for (int networkType : networkTypes) {
                NetworkInfo activeNetwork = manager.getActiveNetworkInfo();
                if (activeNetwork != null && activeNetwork.getType() == networkType) {
                    return true;
                }
            }
        } catch (Exception e) {
            return false;
        }
        return false;
    }

} 

 import android.app.Activity;
import android.os.Build;
import android.widget.Toast;

public class BackPressHandler {
    private long backKeyPressedTime = 0;
    private Toast toast;

    private Activity activity;

    public BackPressHandler(Activity activity) {
        this.activity = activity;
    }

    public void onBackPressed() {

        if (isAfter2Seconds()) {
            backKeyPressedTime = System.currentTimeMillis();
            // 현재시간을 다시 초기화

            toast = Toast.makeText(activity,
                    "\'뒤로\'버튼을 한번 더 누르시면 종료됩니다.",
                    Toast.LENGTH_SHORT);
            toast.show();

            return;
        }

        if (isBefore2Seconds()) {
            appShutdown();
            toast.cancel();
        }
    }

    private Boolean isAfter2Seconds() {
        return System.currentTimeMillis() > backKeyPressedTime + 2000;
        // 2초 지났을 경우
    }

    private Boolean isBefore2Seconds() {
        return System.currentTimeMillis() <= backKeyPressedTime + 2000;
        // 2초가 지나지 않았을 경우
    }

    private void appShutdown() {
        if (Build.VERSION.SDK_INT >= 21) {
            activity.finishAndRemoveTask(); // Activity를 종료하고 최근 앱 사용 목록에서도 해당 앱을 제거
        } else {
            activity.finish();
        }
        System.runFinalization(); // 작업중인 쓰레드가 다 종료되면, 종료 시키라는 명령어
        System.exit(0); // 현재 Activity 종료
    }
}

 public class Main extends Activity {
    private BackPressHandler backPressHandler;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        backPressHandler = new BackPressHandler(this); // 뒤로 가기 버튼 이벤트

    } // onCreate End

    @Override
    public void onBackPressed() {
        backPressHandler.onBackPressed();
    }

}

Button mms_send = (Button) findViewById(R.id.btn_mms);
mms_send.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        String strPhone = "010-1234-5580";
        String strMessage = "전화주셔서 감사합니다.\n좋은 하루되세요.\n
            행복한 하루, 즐거운 하루, 즐거운 저녁\n
            행복하세요...\n행복은 마음에서..\n
            행복하세요...\n행복은 마음에서..\n
            행복하세요...\n행복은 마음에서..\n
            행복하세요...\n행복은 마음에서..\n
            행복하세요...\n행복은 마음에서..\n
            행복하세요...\n행복은 마음에서..";
        String strAttachUrl = "file://"+ Environment.getExternalStorageDirectory()+"/test.jpg";

        Uri uri = Uri.parse("file://"+ Environment.getExternalStorageDirectory()+"/test.jpg");
        Log.e("strAttachUrl : ", strAttachUrl);
        Log.e("imagePath : ", uri.getPath());

        Intent sendIntent = new Intent(Intent.ACTION_SEND);
        sendIntent.setClassName("com.android.mms", "com.android.mms.ui.ComposeMessageActivity");
        sendIntent.putExtra("address", strPhone);
        sendIntent.putExtra("sms_body", strMessage);
        sendIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse(strAttachUrl));
        sendIntent.setType("image/jpg");
        sendIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        startActivity(sendIntent);
    }
});

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "25.0.0"

    defaultConfig {
        applicationId "com.tistory.link2me.login"
        minSdkVersion 19
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:support-v4:23.0.0'
    compile 'com.android.support:appcompat-v7:23.0.0'
    compile 'com.android.support.constraint:constraint-layout:1.0.2'
    compile 'com.squareup.okhttp3:okhttp:3.9.0'

}

'기본적'으로 안드로이드에는 '어플리케이션 종료' 라는 개념 자체가 없다.
한 번 실행된 프로세스는 메모리가 허락하는 한 영원히 죽지 않는다.