来自服务的通知

Question

我正在尝试在收到C2DM消息时显示简单的通知.服务提供给UI,但仍然在主线程上运行.我见过有人声称你可以从服务中创建和显示通知.

 @Override
public void onMessage(Context context, Intent intent) {
    Log.w("Messsage","Message Received");
    Bundle extras = intent.getExtras();
    if (extras != null) {
        String payload = (String) extras.get("test");
        createNotification(context,payload);





    }
}

private void createNotification(Context context, String message){
    NotificationManager notificationmanager =  (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    Notification notification = new Notification(R.drawable.default1,message,System.currentTimeMillis());


    notificationmanager.notify(0,notification);
}

}

06-15 15:39:13.580: E/AndroidRuntime(11603): FATAL EXCEPTION: IntentService    [stp.chrome@gmail.com]
06-15 15:39:13.580: E/AndroidRuntime(11603): java.lang.IllegalArgumentException:   contentView required: pkg=com.upmc id=0 notification=Notification(contentView=null vibrate=null,sound=null,defaults=0x0,flags=0x0)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.os.Parcel.readException(Parcel.java:1331)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.os.Parcel.readException(Parcel.java:1281)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.app.INotificationManager$Stub$Proxy.enqueueNotificationWithTag(INotificationManager.java:299)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.app.NotificationManager.notify(NotificationManager.java:124)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.app.NotificationManager.notify(NotificationManager.java:103)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at com.upmc.C2DMReceiver.createNotification(C2DMReceiver.java:80)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at com.upmc.C2DMReceiver.onMessage(C2DMReceiver.java:66)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at com.google.android.c2dm.C2DMBaseReceiver.onHandleIntent(C2DMBaseReceiver.java:108)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.os.Handler.dispatchMessage(Handler.java:99)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.os.Looper.loop(Looper.java:137)
06-15 15:39:13.580: E/AndroidRuntime(11603):    at android.os.HandlerThread.run(HandlerThread.java:60)

我不知道为什么抛出这个异常.

Answer 1

首先,抛出异常是因为您创建了一个没有引用视图对象的通知(contentView属性设置为null).您必须在显示通知之前调用setLatestEventInfo.

其次,不推荐使用您正在使用的构造函数.请使用Notification.Builder类创建通知.如果您支持Android <API级别11,则可以使用支持库中的NotificationCompat.Builder类.

第三,是的,可以从正在运行的服务创建通知.