注册时触发BroadcastReceiver onReceive

Question

我有一个广播接收器，它在注册时被触发（随后用onPause / onResume重新触发），这肯定是错误的行为？ 我错过了什么吗？

class FooActivity extends Activity {    

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        broadcastReceiver = new FooBroadcastReceiver();
        intentFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
    }

    @Override
    protected void onResume() {
        super.onResume();
        registerReceiver(connectivityReceiver, intentFilter);         
    }

    @Override
    protected void onPause() {
        super.onPause();
        unregisterReceiver(connectivityReceiver);
    }


class MyBroadcastReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {       
        if (connectivityAction(intent)) {
            Log.d("footag", "onReceive");
        }
    }

    private boolean connectivityAction(Intent intent) {
        return ConnectivityManager.CONNECTIVITY_ACTION.equals(intent.getAction());
    }

}

Answer 1

CONNECTIVITY_ACTION广播似乎在某些设备上很粘（即使文档暗示它不是）。 这意味着当您注册接收器时，它将立即使用最近发送的广播呼叫onReceive() 。 由于您在onPause()和onResume()中注册和取消注册，因此您将获得对onReceive()的大量调用。 您可能希望以不同的方式执行此操作。

Answer 2

谢谢你的回答！ 我的解决方案是他们所有的结果，通过切换到清单声明的接收器并在onResume / onPause中启用/禁用接收器组件停止了接收器的粘性。 通过启用/禁用组件，我可以放心，我是二等公民。

@Override
protected void onResume() {
    super.onResume();
    setReceiverState(PackageManager.COMPONENT_ENABLED_STATE_ENABLED);
}

@Override
protected void onPause() {
    super.onPause();
    setReceiverState(PackageManager.COMPONENT_ENABLED_STATE_DISABLED);
}


private void setReceiverState(int receiverState) {
    ComponentName receiver = new ComponentName(this, FooBroadcastReceiver.class);
    PackageManager pm = this.getPackageManager();
    pm.setComponentEnabledSetting(receiver, receiverState,       
    PackageManager.DONT_KILL_APP);
}

AndroidManifest.xml中

<receiver android:name="com.example.receiver.FooBroadcastReceiver">
  <intent-filter>
    <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
  </intent-filter>
</receiver>

Answer 3

这是另一个对我有用的解决方案：

class FooActivity extends Activity {    

    private Intent mReceiverRegisteringIntent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        broadcastReceiver = new FooBroadcastReceiver();
        intentFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
    }

    @Override
    protected void onResume() {
        super.onResume();
        mReceiverRegisteringIntent = registerReceiver(connectivityReceiver, intentFilter);         
    }

    @Override
    protected void onPause() {
        super.onPause();
        unregisterReceiver(connectivityReceiver);
    }


    private class MyBroadcastReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {       
            if (connectivityAction(intent)) {
                Log.d("footag", "onReceive");
                //if mReceiverRegisteringIntent is not null, then this is the sticky
                //broadcast received when registering the receiver for the first time
                if (mReceiverRegisteringIntent != null) {
                    //set it to null for future broadcasts
                    mReceiverRegisteringIntent = null;
                    return; //do nothing
                }

                //logic for future broadcasts
                ...
            }
        }

        private boolean connectivityAction(Intent intent) {
            return ConnectivityManager.CONNECTIVITY_ACTION.equals(intent.getAction());
        }
    }

}

我假设MyBroadcastReceiver是一个内部类FooActivity以便它可以访问mReceiverRegisteringIntent

Answer 4

删除以下两行，它们不会在onPause和onResume中触发！

registerReceiver(connectivityReceiver, intentFilter);
unregisterReceiver(connectivityReceiver);