广播接收器vs唤醒广播接收器

广播接收器vs唤醒广播接收器

BroadcastReceiver

和之间只有一个区别

WakefulBroadcastReceiver

。

当您收到内部广播

onReceive()

方法时，

假设，

BroadcastReceiver ：

• 它 不保证 该 CPU将保持清醒 ，如果你启动一些长时间运行的进程。CPU可能会立即回到睡眠状态。

WakefulBroadcastReceiver ：

• 这是 保证 该 CPU将保持清醒 ，直到你开除

  completeWakefulIntent

  。

例：

在这里，当您接收广播时，即表示您正在使用的方式启动一项服务，直到您完成服务中的工作并触发后

WakefulBroadcastReceiver

，它将保持

wakelock

并且不会让CPU进入睡眠状态

completeWakefulIntent

码：

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);    }}