Ошибка “the task has already been executed (a task can be executed only once)” в AsyncTask

#java #android

public class MainActivity extends AppCompatActivity {

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

        Button get_string_button = (Button) findViewById(R.id.get_string_button);
        Button get_screen_button = (Button) findViewById(R.id.get_screen_button);
        final SenderThread senderThread = new SenderThread();

        View.OnClickListener onClickListener = new View.OnClickListener() {
        String line;
        Toast toast;

        @Override
        public void onClick(View view) {
            try {
                switch (view.getId()){
                    case R.id.get_string_button:
                        senderThread.execute("getRandomNumber");
                        line = senderThread.get();
                        toast = Toast.makeText(getApplicationContext(), line, Toast.LENGTH_LONG);
                        toast.show();
                        break;
                    case R.id.get_screen_button:
                        senderThread.execute("getScreen");
                        line = senderThread.get();
                        toast = Toast.makeText(getApplicationContext(), line, Toast.LENGTH_LONG);
                        toast.show();
                        break;
                }
            } catch (InterruptedException e) {
                Toast toast = Toast.makeText(getApplicationContext(), e.toString(),
Toast.LENGTH_LONG);
                toast.show();
            } catch (ExecutionException e) {
                e.printStackTrace();
            }
        }

    };
    get_string_button.setOnClickListener(onClickListener);
    get_screen_button.setOnClickListener(onClickListener);
 }

}


SenderThread

class SenderThread extends  AsyncTask {

private Socket socket;
InputStream sin;
OutputStream sout;
DataInputStream in;
DataOutputStream out;
CloseSocket closeSocket = new CloseSocket();

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

@Override
protected String doInBackground(String... params) {

    String line;
    String command = params[0];

    try{
            socket = new Socket(ip, 6666);
            sin = socket.getInputStream();
            sout = socket.getOutputStream();
            in = new DataInputStream(sin);
            out = new DataOutputStream(sout);
        if(socket.isConnected()) {
            out.writeUTF(command);
            out.flush();
            line = in.readUTF();
            closeSocket.close(in,out,socket);
            return line.toString();
        }else{
            throw new Exception("Socket not alive!");
        }
     }catch(Exception ex) {
        return ex.toString();
    }
 }
}


logcat 

E/AndroidRuntime: FATAL EXCEPTION: main
                                                                  Process: com.lordradix.client,
PID: 21168
                                                                  java.lang.IllegalStateException:
Cannot execute task: the task has already been executed (a task can be executed only once)
                                                                      at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:605)
                                                                      at android.os.AsyncTask.execute(AsyncTask.java:560)
                                                                      at com.lordradix.client.MainActivity$1.onClick(MainActivity.java:44)
                                                                      at android.view.View.performClick(View.java:6261)
                                                                      at android.widget.TextView.performClick(TextView.java:11159)
                                                                      at android.view.View$PerformClick.run(View.java:23748)
                                                                      at android.os.Handler.handleCallback(Handler.java:751)
                                                                      at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                      at android.os.Looper.loop(Looper.java:154)
                                                                      at android.app.ActivityThread.main(ActivityThread.java:6776)
                                                                      at java.lang.reflect.Method.invoke(Native
Method)
                                                                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1496)
                                                                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1386)

    

Ответы

Ответ 1

Точно не помню, но по моему один экземпляр AsyncTask нельзя использовать дважды.
Создайте другой экземпляр для второго клика, так например:

switch (view.getId()){
       case R.id.get_string_button:
             SenderThread senderThread = new SenderThread();
             senderThread.execute("getRandomNumber");
             line = senderThread.get();
             toast = Toast.makeText(getApplicationContext(), line, Toast.LENGTH_LONG);
             toast.show();
             break;
      case R.id.get_screen_button:
             SenderThread senderThread = new SenderThread();
             senderThread.execute("getScreen");
             line = senderThread.get();
             toast = Toast.makeText(getApplicationContext(), line, Toast.LENGTH_LONG);
             toast.show();
             break;
 }


Вам компилятор подсказывает:


  the task has already been executed (a task can be executed only once)


То есть


  задача уже выполнена (задача может быть выполнена только один раз)