從IntentService發送信息到活動

我的問題是，我如何從我的後臺運行IntentService到主活動發送字符串「消息」（RISES和DROPS）？我想在UI中顯示此消息。從IntentService發送信息到活動

我試圖使用EventBus，因爲它需要更少的代碼，理論上對用戶來說應該更簡單，但不幸的是，它嘗試在onCreate方法中註冊訂戶時崩潰了應用程序。謝謝！

MainActivity.java

import android.app.Activity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.Menu; 
import android.view.View; 

public class MainActivity extends Activity { 


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

} 

@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.menu_main, menu); 
    return true; 
} 

public void startService(View view) { 
    Intent intent = new Intent(this, MyService.class); 
    startService(intent); 
} 

// Method to stop the service 
public void stopService(View view) { 
    stopService(new Intent(getBaseContext(), MyService.class)); 
    System.exit(0); 
} 
}

MyService.java EDITED

import android.app.IntentService; 
import android.app.Service; 
import android.content.Intent; 
import android.media.AudioFormat; 
import android.media.AudioRecord; 
import android.media.MediaRecorder; 
import android.util.Log; 
import android.widget.Toast; 



public class MyService extends IntentService { 

public MyService() { 
    super("MyService"); 
} 

@Override 
protected void onHandleIntent(Intent intent) { 

    Runnable r = new Runnable() { 
     public void run() { 

      final int RECORDER_SAMPLERATE = 8000; 
      final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO; 
      final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT; 
      int frequency; 
      AudioRecord recorder; 
      int numCrossing, p, numSamples; 
      short audioData[]; 
      boolean recording; 

      int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE, 
        RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING); 

      recorder = new AudioRecord(MediaRecorder.AudioSource.MIC, 
        RECORDER_SAMPLERATE, RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING, bufferSize); 

      recorder.startRecording(); 
      recording = true; 
      audioData = new short[bufferSize]; 
      int[] values; 
      int k = 0, t = 0; 

      values = new int[2]; 

      while (recording) { 
       numCrossing = 0; 
       numSamples = 0; 
       recorder.read(audioData, 0, bufferSize); 
       int mod = (bufferSize/4) * 4; 

       for (p = 0; p < mod; p += 4) { 
        if (audioData[p] > 0 && audioData[p + 1] <= 0) numCrossing++; 
        if (audioData[p] < 0 && audioData[p + 1] >= 0) numCrossing++; 
        if (audioData[p + 1] > 0 && audioData[p + 2] <= 0) numCrossing++; 
        if (audioData[p + 1] < 0 && audioData[p + 2] >= 0) numCrossing++; 
        if (audioData[p + 2] > 0 && audioData[p + 3] <= 0) numCrossing++; 
        if (audioData[p + 2] < 0 && audioData[p + 3] >= 0) numCrossing++; 
        if (audioData[p + 3] > 0 && audioData[p + 4] <= 0) numCrossing++; 
        if (audioData[p + 3] < 0 && audioData[p + 4] >= 0) numCrossing++; 
        numSamples += 4; 
       } 
       for (p = 0; p < bufferSize; p++) { 
        if (audioData[p] > 0 && audioData[p + 1] <= 0) numCrossing++; 
        if (audioData[p] < 0 && audioData[p + 1] >= 0) numCrossing++; 
        numSamples++; 
       } 

       frequency = (8000/numSamples) * numCrossing; 

       Log.d("proov", String.valueOf(frequency)); 

       if (frequency >= 2550 && frequency <= 2750 && (values[0] != 2)) { 
        values[0] = 1; 
        values[1] = 2; 
        k = 1; 
       }//if 

       if (frequency <= 3090 && frequency >= 2900 && (values[0] == 0)) { 
        values[0] = 2; 
        values[1] = 1; 
        k = 1; 
       }//if 

       if (frequency <= 3090 && frequency >= 2900 && (values[0] == 1)) { 
        t = 1; 
        break; 
       }//if 

       if (frequency >= 2550 && frequency <= 2750 && (values[0] == 2)) { 
        t = 2; 
        break; 
       }//if 

       if (k != 0) { 
        k = k + 1; 
       }//if 

       if (k == 20) { 
        values[0] = 0; 
        values[1] = 0; 
       }//if 

      }//while 

      if (t == 1) { 
       String message = "RISES"; 
       values[0] = 0; 
       values[1] = 0; 

      }//if 

      if (t == 2) { 
       String message = "DROPS"; 
       values[0] = 0; 
       values[1] = 0; 

      }//if 
     } 
    }; 

    Thread t = new Thread(r); 
    t.start(); 
    //return Service.START_STICKY; 
} 

@Override 
public void onDestroy() { 
    super.onDestroy(); 
    Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show(); 
}

來源

2015-06-20 AlarMa

您正在使用IntentService錯誤。我們使用'onHandleIntent'方法來做你的後臺工作 - 你不需要產生你自己的線程。 – Blundell

我知道我做了很多錯誤的事情，但不幸的是這只是我得到它的工作方式;）當代碼在onHandleIntent中時，它沒有做任何事情。我想我不知道如何正確啓動HandleIntent。 – AlarMa

因此，用我做的代碼是不可能發送信息到主要活動？ – AlarMa

您可以使用：

public class APIResultReceive extends ResultReceiver { 

    private final static String TAG = "APIResultReceive"; 
    public final static int API_START = 1; 
    public final static int API_END = 2; 
    public final static int API_SUCCESS = 3; 
    public final static int API_FAIL = 4; 
    private Receive receive = null; 

    public interface Receive { 

     public void onReceiveResult(int resultCode, Bundle resultData); 
    } 

    public APIResultReceive(Handler handler) { 
     super(handler); 
    } 

    public void setReceive(Receive receive) { 
     this.receive = receive; 
    } 

    @Override 
    protected void onReceiveResult(int resultCode, Bundle resultData) { 
     super.onReceiveResult(resultCode, resultData); 
     if (receive != null) { 
      receive.onReceiveResult(resultCode, resultData); 
     } 
    } 
}

在您的服務：

@Override 
protected void onHandleIntent(Intent intent) { 
    sendData(
     intent.getIntExtra(EXTRA_COUNT, 0), 
     (ResultReceiver) intent.getParcelableExtra(EXTRA_RECEIVE) 
    ); 
} 

private void sendData(int count, ResultReceiver resultReceive) { 
    resultReceive.send(APIResultReceive.API_START, null); 

    for (int i = 0; i < count; i++) { 
     Log.i(TAG, "i = " + i); 
     SystemClock.sleep(1000); 
    } 

    resultReceive.send(APIResultReceive.API_END, null); 
} 

public static void sendData(Context context, int count, APIResultReceive resultReceive) { 
    Intent intent = new Intent(context, APIService.class); 
    intent.putExtra(EXTRA_COUNT, count); 
    intent.putExtra(EXTRA_RECEIVE, resultReceive); 
    context.startService(intent); 
}

，最後你的活動：

public class MyActivity extends Activity implements APIResultReceive.Receive { 

    private final static String TAG = "MyActivity"; 
    private APIResultReceive resultReceive = null; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     Log.i(TAG, "onCreate"); 

     resultReceive = new APIResultReceive(new Handler()); 
     resultReceive.setReceive(this); 

     // start send data 
     APIService.sendData(this, 10, resultReceive); 
    } 

    @Override 
    protected void onResume() { 
     super.onResume(); 
     Log.i(TAG, "onResume"); 
    } 

    @Override 
    protected void onDestroy() { 
     super.onDestroy(); 
     Log.i(TAG, "onDestory"); 
     resultReceive.setReceive(null); 
    } 

    @Override 
    public void onReceiveResult(int resultCode, Bundle resultData) { 
     switch (resultCode) { 
      case APIResultReceive.API_START: 
       Log.d(TAG, "APIResultReceive.API_START"); 
       break; 
      case APIResultReceive.API_SUCCESS: 
       Log.d(TAG, "APIResultReceive.API_SUCCESS"); 
       break; 
      case APIResultReceive.API_FAIL: 
       Log.d(TAG, "APIResultReceive.API_FAIL"); 
       break; 
      case APIResultReceive.API_END: 
       Log.d(TAG, "APIResultReceive.API_END"); 
       break; 
     } 
    } 
}

來源

2015-06-20 10:32:25 Helmi

-1

您可以使用廣播接收器。這是它的documentaion。

這裏的示例代碼：

MyService.java

@Override 
public int onStartCommand(Intent intent, int flags, int startId) { 
    Intent sendIntent = new Intent("send_message"); 
    sendIntent.putExtra("message","RISES"); 
    sendBroadcast(sendIntent); 
}

MainActivity.java

BroadcastReceiver mMessageReceiver; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    mMessageRecevier = new BroadcastReceiver() { 
      @Override 
      public void onReceive(Context context, Intent intent) { 
       String message = intent.getStringExtra("message"); 
       //Do whatever you want with message 
      } 
    }; 
} 

@Override 
public void onResume() { 
    super.onResume(); 
    IntentFilter intentFilter = new IntentFilter("send_message"); 
    registerReceiver(mMessageRecevier, intentFilter); 
} 

@Override 
public void onPause() { 
    super.onPause(); 
    unregisterReceiver(mMessageRecevier); 
}

我希望它能幫助。

來源

2015-06-20 10:44:11 suheb

從IntentService發送信息到活動

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