[코틀린] Retrofit2 데이터 처리 파헤치기

코틀린에서 Retrofit2 라이브러리를 이용하여 서버 데이터를 가져오는 기능을 처리하는데 헷갈려서 정리를 좀 해둔다.

예제1)

먼저 PHP 코드에서 JSON 데이터를 만드는 방법

$R = array(); // 결과 담을 변수 생성     $result = $c->putDbArray($sql);     while($row = $result->fetch_assoc()) {         if($row['photo'] == NULL) {             $row['photo'] = "";         } else {             $path = "./photos/".$row['photo'];             if(!file_exists($path)) {                 $row['photo'] = "";             }         }         array_push($R, $row);     }     header("Cache-Control: no-cache, must-revalidate");     header("Content-type: application/json; charset=UTF-8");     $status = "success";     $result = array(         'status' => $status,         'message' => $R     );     echo json_encode($result);

while 문을 사용했다는 것은 $R 변수는 배열이라는 것을 명심하자.

서버에서 받은 데이터를 Retrofit 라이브러리에서 받아서 처리하기 위한 data class

@Parcelize data class ContactData (     // PersonData 정보를 담고 있는 객체 생성     var idx: String,     var userNM: String = "",     var mobileNO: String = "",     var officeNO: String = "",     var photo: String = "", // 이미지 경로를 String으로 받기 위해서     var isCheckBoxState: Boolean = false ): Parcelable

@Parcelize class ContactDataResult (     val status: String,     val message: List<ContactData> ): Parcelable

interface IRetrofit {     @FormUrlEncoded     @POST(Value.Contacts)     fun getContactDataResult(@Field("idx") idx: String): Call<ContactDataResult> }

Retrofit 라이브러리 사용법

object RetroClient { // 싱글턴     // 레트로핏 클라어언트 선언     private var retrofitClient: Retrofit? = null     var instance: IRetrofit? = null     val gson = GsonBuilder().setLenient().create()     // 레트로핏 클라어언트 가져오기     fun getClient(baseUrl: String): Retrofit? {         if (retrofitClient == null){             retrofitClient = Retrofit.Builder()                 .baseUrl(baseUrl)                 .addConverterFactory(GsonConverterFactory.create(gson))                 .client(Utils.createOkHttpClient())                 .build()         }         return retrofitClient     }     @JvmName("getInstance1")     fun getInstance(): IRetrofit? {         if (instance == null) {             instance = getClient(Value.API_BASE_URL)?.create(IRetrofit::class.java)         }         return instance     } }

class Value : AppCompatActivity() {     companion object{         const val API_BASE_URL = "https://test.abc.com/androidSample/"         const val Photo_URL = "https://test.abc.com/androidSample/photos/"         const val Contacts = "getContactData.php"     } }

private fun getServerData() {         RetroClient.getInstance()?.getContactDataResult("1")?.enqueue(object :             Callback<ContactDataResult> {             override fun onResponse(call: Call<ContactDataResult>, response: Response<ContactDataResult>) {                 if (response.body()!!.status.contains("success")){                     addressItemList.clear()                     searchItemList.clear()                     val contactData = response.body()!!.message                     for (item in contactData){                         addressItemList.add(item)                         searchItemList.add(item)                     }                     runOnUiThread { // 갱신된 데이터 내역을 어댑터에 알려줌                         mAdapter.notifyDataSetChanged()                     }                 }             }             override fun onFailure(call: Call<ContactDataResult>, t: Throwable) {                 Log.e(TAG,"Retrofit response fail.")             }         })     }

예제2)

PHP 코드 수정사항

echo json_encode(array('message'=>$R));

결과 형태

{"message":[{"idx":1,"userNM":"\uac1c\ubc1c\uc790","mobileNO":"01000010001","telNO":"0234560001","photo":"1.jpg"}, {"idx":2,"userNM":"\uc774\uc815\uc740","mobileNO":"01001230001","telNO":"","photo":"2.jpg"}, {"idx":3,"userNM":"\uae40\ud64d\uae38","mobileNO":"01001230002","telNO":"","photo":""}, {"idx":4,"userNM":"\ucd5c\uc2e0\ud615","mobileNO":"01001230003","telNO":"","photo":"4.jpg"}]}

코틀린 수정사항

@Parcelize class ContactDataResult (     val message: List<ContactData> ): Parcelable

// 수정사항 없음 @Parcelize data class ContactData (     // PersonData 정보를 담고 있는 객체 생성     var idx: String,     var userNM: String = "",     var mobileNO: String = "",     var officeNO: String = "",     var photo: String = "", // 이미지 경로를 String으로 받기 위해서     var isCheckBoxState: Boolean = false ): Parcelable

RetroClient.getInstance()?.getContactDataResult("1")?.enqueue(object :             Callback<ContactDataResult> {             override fun onResponse(call: Call<ContactDataResult>, response: Response<ContactDataResult>) {                 if (response.isSuccessful){                     addressItemList.clear()                     searchItemList.clear()                     val contactData = response.body()!!.message                     for (item in contactData){                         addressItemList.add(item)                         searchItemList.add(item)                     }                     runOnUiThread { // 갱신된 데이터 내역을 어댑터에 알려줌                         mAdapter.notifyDataSetChanged()                     }                 }             }             override fun onFailure(call: Call<ContactDataResult>, t: Throwable) {                 Log.e(TAG,"Retrofit response fail.")             }         })

예제3)

PHP 코드 수정사항

echo json_encode($R);

JSON 결과==> 배열

[{"idx":1,"userNM":"\uac1c\ubc1c\uc790","mobileNO":"01000010001","telNO":"0234560001","photo":"1.jpg"},  {"idx":2,"userNM":"\uc774\uc815\uc740","mobileNO":"01001230001","telNO":"","photo":"2.jpg"},  {"idx":3,"userNM":"\uae40\ud64d\uae38","mobileNO":"01001230002","telNO":"","photo":""},  {"idx":4,"userNM":"\ucd5c\uc2e0\ud615","mobileNO":"01001230003","telNO":"","photo":"4.jpg"},  {"idx":5,"userNM":"\ud64d\uae38\ub3d9","mobileNO":"01000009880","telNO":"","photo":"5.jpg"}]

코틀린 수정사항

interface IRetrofit {     @FormUrlEncoded     @POST(Value.Contacts)     fun getContactsList(@Field("idx") idx: String): Call<List<ContactData>> }

RetroClient.getInstance()?.getContactsList("1")?.enqueue(object :             Callback<List<ContactData>> {             override fun onResponse(call: Call<List<ContactData>>, response: Response<List<ContactData>>) {                 if (response.isSuccessful){                     addressItemList.clear()                     searchItemList.clear()                     val contactData = response.body()!!                     for (item in contactData){                         addressItemList.add(item)                         searchItemList.add(item)                     }                     runOnUiThread { // 갱신된 데이터 내역을 어댑터에 알려줌                         mAdapter.notifyDataSetChanged()                     }                 }             }             override fun onFailure(call: Call<List<ContactData>>, t: Throwable) {                 Log.e(TAG,"Retrofit response fail.")             }         })

예제4) JSON 파싱하기

PHP 코드 수정사항

echo json_encode(array('result'=>$R));

JSON 결과

{"result":[{"idx":1,"userNM":"\uac1c\ubc1c\uc790","mobileNO":"01000010001","telNO":"0234560001","photo":"1.jpg"},            {"idx":2,"userNM":"\uc774\uc815\uc740","mobileNO":"01001230001","telNO":"","photo":"2.jpg"},        {"idx":3,"userNM":"\uae40\ud64d\uae38","mobileNO":"01001230002","telNO":"","photo":""},        {"idx":4,"userNM":"\ucd5c\uc2e0\ud615","mobileNO":"01001230003","telNO":"","photo":"4.jpg"},        {"idx":5,"userNM":"\ud64d\uae38\ub3d9","mobileNO":"01000009880","telNO":"","photo":"5.jpg"}]}

코틀린 수정사항

interface IRetrofit {     @FormUrlEncoded     @POST(Value.Contacts)     fun getContactsObject(@Field("idx") idx: String): Call<JsonObject> }

object ContactContract {     const val _RESULTS = "result" // 서버 정보를 파싱하기 위한 변수 선언     object Entry : BaseColumns {         const val TABLE_NAME = "PBbook"         const val _IDX = "idx" // 서버 테이블의 실제 필드명         const val _NAME = "userNM"         const val _MobileNO = "mobileNO"         const val _telNO = "telNO"         const val _Team = "Team"         const val _Mission = "Mission"         const val _Position = "Position"         const val _Photo = "photo" // 이미지 필드         const val _Status = "status"     } // SQLite의 데이터 타입은 NULL, INTEGER, REAL, TEXT, BLOB 만 지원한다. }

=== MainActivity.kt 파일에서 발췌 ===     private fun getServerData() {         RetroClient.getInstance()?.getContactsObject("1")?.enqueue(object :             Callback<JsonObject> {             override fun onResponse(call: Call<JsonObject>, response: Response<JsonObject>) {                 if (response.isSuccessful){                     addressItemList.clear()                     searchItemList.clear()                     val jsonObj = JSONObject(response.body().toString())                     val person = jsonObj.getJSONArray(ContactContract._RESULTS)                     for (i in 0 until person.length()) {                         val c = person.getJSONObject(i)                         val idx = c.getString(ContactContract.Entry._IDX)                         val name = c.getString(ContactContract.Entry._NAME)                         val mobileNO = c.getString(ContactContract.Entry._MobileNO)                         val officeNO = c.getString(ContactContract.Entry._telNO)                         val PhotoImage = c.getString(ContactContract.Entry._Photo)                         Log.e(TAG,"name : " + name)                         getAllDataList(idx, name, mobileNO, officeNO, PhotoImage, false)                         selectDataList(idx, name, mobileNO, officeNO, PhotoImage, false)                     }                     runOnUiThread { // 갱신된 데이터 내역을 어댑터에 알려줌                         mAdapter.notifyDataSetChanged()                     }                 }             }             override fun onFailure(call: Call<JsonObject>, t: Throwable) {                 Log.e(TAG,"Retrofit response fail.")             }         })     }       // 아이템 전체 데이터 추가 메소드     fun getAllDataList(uid: String, name: String, mobileNO: String, officeNO: String, photo_image: String, checkItem_flag: Boolean) {         val item = ContactData(uid, name, mobileNO, officeNO, photo_image, checkItem_flag)         addressItemList.add(item)     }     // 선택한 데이터 추가 메소드     fun selectDataList(uid: String, name: String, mobileNO: String, officeNO: String, photo_image: String, checkItem_flag: Boolean) {         val item = ContactData(uid, name, mobileNO, officeNO, photo_image, checkItem_flag)         searchItemList.add(item)     }