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BroadcastReceiver対WakefulBroadcastReceiver

誰かが BroadcastReceiver と WakefulBroadcastReceiver の正確な違いを説明できますか？

どのような状況で各Receiverクラスを使用する必要がありますか？

javaandroidbroadcastreceiverwakelock
61
user2107111

BroadcastReceiverとWakefulBroadcastReceiverの違いは1つだけです。

onReceive()メソッド内でブロードキャストを受信すると、

、

BroadcastReceiver：

  • 保証されていませんCPUは起動したままです長時間実行されているプロセスを開始した場合。 CPUはすぐにスリープ状態に戻る場合があります。

WakefulBroadcastReceiver：

  • 保証CPUはアウェイク状態のままcompleteWakefulIntentを起動するまでです。

例：

ここで、ブロードキャストを受信すると、WakefulBroadcastReceiverを使用しているため、サービスを開始します。wakelockを保持し、サービス内での作業を完了して起動するまでCPUをスリープさせません。 completeWakefulIntent

コード：

public class SimpleWakefulReceiver extends WakefulBroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        // This is the Intent to deliver to our service.
        Intent service = new Intent(context, SimpleWakefulService.class);

        // Start the service, keeping the device awake while it is launching.
        Log.i("SimpleWakefulReceiver", "Starting service @ " + SystemClock.elapsedRealtime());
        startWakefulService(context, service);
    }
}

class SimpleWakefulService extends IntentService {
    public SimpleWakefulService() {
        super("SimpleWakefulService");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        // At this point SimpleWakefulReceiver is still holding a wake lock
        // for us.  We can do whatever we need to here and then tell it that
        // it can release the wakelock.  This sample just does some slow work,
        // but more complicated implementations could take their own wake
        // lock here before releasing the receiver's.
        //
        // Note that when using this approach you should be aware that if your
        // service gets killed and restarted while in the middle of such work
        // (so the Intent gets re-delivered to perform the work again), it will
        // at that point no longer be holding a wake lock since we are depending
        // on SimpleWakefulReceiver to that for us.  If this is a concern, you can
        // acquire a separate wake lock here.
        for (int i=0; i<5; i++) {
            Log.i("SimpleWakefulReceiver", "Running service " + (i+1)
                    + "/5 @ " + SystemClock.elapsedRealtime());
            try {
                Thread.sleep(5000);
            } catch (InterruptedException e) {
            }
        }
        Log.i("SimpleWakefulReceiver", "Completed service @ " + SystemClock.elapsedRealtime());
        SimpleWakefulReceiver.completeWakefulIntent(intent);
    }
}
105
Mehul Joisar