Android/カスタムListener

独自Listenerを作る方法

足し算処理を例にする

-CustomData.java

public class CustomData {
   public int code;
   public String message;
   public CustomData(int code, String message) {
       this.code = code;
       this.message = message;
   }
}

-CustomListener.java

public interface CustomListener {
   void onLoad(CustomData data);
   void onStart(CustomData data);
   void onSuccess(CustomData data);
   void onError(CustomData data);
   void onFinish(CustomData data);
   void onClose(CustomData data);
}

-CustomTask.java

public class CustomTask {
   private CustomListener mListener;
   private CustomData data;
   CustomTask() {
       data = new CustomData(123, "hello");
   }
   public void exec(int num, int addnum, int sum) {
       mListener.onLoad(data);
       mListener.onStart(data);
       if (num + addnum == sum) {
           data.message = "success " + num + "+" + addnum + "=" + sum;
           mListener.onSuccess(data);
       } else {
           data.message = "error " + num + "+" + addnum + "!=" + sum;
           mListener.onError(data);
       }
       mListener.onFinish(data);
       mListener.onClose(data);
   }
   public void setCustomListener(CustomListener listener) {
       mListener = listener;
   }
}

-メイン処理(MainActivity.java)

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        CustomListener listener = new CustomListener() {
            @Override
            public void onLoad(CustomData data) {
                Log.i("test", "task onLoad()");
            }
            @Override
            public void onStart(CustomData data) {
                Log.i("test", "task onStart()");
            }
            @Override
            public void onSuccess(CustomData data) {
                Log.i("test", "task onSuccess() code=" + data.code + " " + data.message);
            }
            @Override
            public void onError(CustomData data) {
                Log.i("test", "task onError() code=" + data.code + " " + data.message);
            }
            @Override
            public void onFinish(CustomData data) {
                Log.i("test", "task onFinish()");
            }
            @Override
            public void onClose(CustomData data) {
                Log.i("test", "task onClose()");
            }
        };
        CustomTask task = new CustomTask();
        task.setCustomListener(listener);
        task.exec(1, 1, 2); // 処理1
        task.exec(1, 1, 3); // 処理2
    }
}

処理1

test: onLoad()
test: onStart()
test: onSuccess() code=123 success 1+1=2
test: onFinish()
test: onClose()

処理2

test: onLoad()
test: onStart()
test: onError() code=123 error 1+1!=3
test: onFinish()
test: onClose()