android - 将字符串从服务发送到 Activity

Question

我正在尝试通过广播将字符串从服务发送到我的主要 Activity 。我在一些论坛上看到有两种使用广播的方法。一种是在 list 中注册 Activity ，第二种方法是在本地 Activity 上进行。我想知道如何使用第二种方式。我尝试过这样做，但不幸的是我没有成功。

请告诉我我做错了什么。

服务代码

   public class MyGcmListenerService extends GcmListenerService {

private static final String TAG = "MyGcmListenerService";

// [START receive_message]
@Override
public void onMessageReceived(String from, Bundle data) {
    String typemessage = data.getString("typemessage"); // typeMessage = 0 or 1 = lock or unlock
    String datamessage = data.getString("datamessage"); // dataMessage = time and message that says lock or unlock

    Log.d(TAG, "TypeMessage: " + typemessage);
    Log.d(TAG,"DataMesaage:"+ datamessage);

    Intent in = new Intent();
    in.putExtra("TYPE",typemessage);
    in.setAction("NOW");
    sendBroadcast(in);
  ...

主要 Activity 代码

    public class MainActivity extends Activity implements SensorEventListener, Listen {

        private BroadcastReceiver statusReceiver;
        private IntentFilter mIntent;


    Sensor accelerometer;
    SensorManager sm;
    TextView acceleration;
    SendValues sv;
    int counter3 = 0;
    int counter5 = 0;

    private static final String TAG = "MainActivity";

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

         mIntent = new IntentFilter("NOW");

      // this.registerReceiver(,new IntentFilter("status"));

        sm = (SensorManager) getSystemService(SENSOR_SERVICE);
        sm.registerListener(this,accelerometer, SensorManager.SENSOR_DELAY_NORMAL);
        accelerometer = sm.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);

        acceleration = (TextView) findViewById(R.id.sensorTxt);

        statusReceiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {

                String type = intent.getStringExtra("message");  //get the type of message from MyGcmListenerService 1 - lock or 0 -Unlock
                sm = (SensorManager) getSystemService(SENSOR_SERVICE);
                accelerometer = sm.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
                Log.d(TAG, "Status: " + type);
                if (type == "1") // 1 == lock
                {
                    Toast.makeText(getApplication(), "Lock", Toast.LENGTH_LONG).show();
                } else {
                    Toast.makeText(getApplication(), "UNLOCK", Toast.LENGTH_LONG).show();
                }
            }

        };
    }

        @Override
         protected void onResume()
         {
            super.onResume();
            registerReceiver(statusReceiver,mIntent);
          }

    @Override
    protected void onPause() {
        if(mIntent != null) {
            unregisterReceiver(statusReceiver);
            mIntent = null;
        }
        super.onPause();
    }


----------

嗯，我不知道我做错了什么，还有一个问题，我需要在

In set Action("我可以在这里放任何我想要的字符串/ Action ？这意味着什么 Action ？我只想将字符串发送到主要 Activity ，我应该做什么 Action "？)

Answer 1

您可以使用 LocalBroadcastManager 来实现您想要的。就像在您的 service 中一样，当您要发送数据时调用此方法。

private static void sendMessageToActivity(String msg) {
  Intent intent = new Intent("intentKey");
  // You can also include some extra data.
  intent.putExtra("key", msg);
  LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
}

在你的 Activity 中在 onCreate()

中注册一个 Receiver

LocalBroadcastManager.getInstance(getActivity()).registerReceiver(mMessageReceiver, new IntentFilter("intentKey"));

从 onCreate() 这段代码中。

private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
  @Override
  public void onReceive(Context context, Intent intent) {
      // Get extra data included in the Intent
      String message = intent.getStringExtra("key");
      tvStatus.setText(message);
      // Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
  }
};