android - START_STICKY，前台 Android 服务消失，恕不另行通知

Question

我已经在我的新应用程序中启动了一项服务。该服务是前台的，带有通知。当它在 AVD 2.1 API Level 7 中运行时，一切正常。但是当它在运行 Gingerbread 的 Samsung Galaxy Tab 上运行时，该服务会启动(图标和应用程序名称出现在通知区域的顶部)，但几秒钟后，该服务就会消失。我可以看到的日志中的最后一个条目与我的应用程序相关联，是我的 Log.d("Taglines","Returning with "+ START_STICKY) 的结果，它紧接在 "return START_STICKY ;"之前在我的服务的 onStartCommand 覆盖中，如下所示:

@Override
public int onStartCommand(Intent intent, int flags, int startId) {

    int rc ;
    Log.d("Taglines","onStartCommand()");
    Toast.makeText(this, "Starting service TagsManager", Toast.LENGTH_SHORT).show();
    Log.d("Taglines","Calling super.onStartCommand()");
    rc = super.onStartCommand(intent,flags,startId);
    Log.d("Taglines","super.onStartCommand return code was " + rc);
    createNotification(INITIAL_NOTIFICATION_TEXT);
    Log.d("Taglines","Returning with " + START_STICKY);
    return START_STICKY ;
}

通知设置如下:

void createNotification(String text) {

    Log.d("Taglines","createNotification called");
    if (mNotificationManager == null) {
        // Get a reference to the Notification Manager
        String ns = Context.NOTIFICATION_SERVICE;
        mNotificationManager = (NotificationManager) getSystemService(ns);
        Log.d("Taglines","Obtained reference to Notification Manager");
    }

    // Instantiate the Notification
    int icon = R.drawable.ic_notification;
    CharSequence tickerText = "Taglines";
    long when = System.currentTimeMillis();

    notification = new Notification(icon, tickerText, when);

    // Define Notification's expanded message and intent
    Log.d("Taglines","createNotificacion() .. getApplicationContext");
    context = getApplicationContext();
    contentText = text;
    // notificationIntent = new Intent(this, TagsOverview.class);
    notificationIntent = new Intent(this, TagsServiceMenu.class);
    contentIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);

    notification.setLatestEventInfo(context, contentTitle, contentText, contentIntent);

    // Pass the Notification to the NotificationManager: 
    Log.d("Taglines","createNotificacion() ... passing notification");
    mNotificationManager.notify(NOTIFICATION_ID, notification);
    Log.d("Taglines","Starting foreground");
    startForeground(NOTIFICATION_ID, notification);
    Log.d("Taglines","Started");
}

这是启动服务时“adb logcat”的结果:

D/Taglines(21863): Starting service
D/Taglines(21863): TagsManager(nullary) completed
D/Taglines(21863): onStartCommand()
D/Taglines(21863): Calling super.onStartCommand()
D/Taglines(21863): super.onStartCommand eturn code was 2
D/Taglines(21863): createNotification called
D/Taglines(21863): Obtained reference to Notification Manager
D/Taglines(21863): createNotificacion() .. getApplicationContext
D/Taglines(21863): createNotificacion() ... passing notification
D/Taglines(21863): Starting foreground
D/Taglines(21863): Started
D/Taglines(21863): Returning with 1

在那之后，没有什么特别的(从 PID 21863 开始就没有了)。只是一堆:

D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
W/InputManagerService(  302): Window already focused, ignoring focus gain of:         com.android.internal.view.IInputMethodClient$Stub$Proxy@40bc06e8
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false
D/KeyguardViewMediator(  302): setHidden false

我认为在这种情况下不需要它，但这里是 AndroidManifest.xml 的相关部分:

    <service android:name=".TagsManager"
             android:exported="false">
    </service>

我可能哪里出错了？我还可以提供哪些其他信息？

Answer 1

一些事情:

1. 摆脱 mNotificationManager.notify(NOTIFICATION_ID, notification);。 startForeground() 为您显示通知图标。

2. 前台 Service 仍然可以被终止，只是可能性较小。

3. 2.3 中有一个错误(不确定是否已修复)，当 Service 被终止并重新启动时，它的 onStartCommand() 将不会又叫了。相反，您必须在 onCreate() 中进行任何设置。