android: 从 Broadcastreceiver 调用函数: 无法启动接收器 ... java.lang.ClassCastException: android.app.ReceiveRestrictedContext

Question

我正在尝试通过通知中操作按钮中的按钮从名为“通知 Activity ”的广播接收器调用名为“TrackingScreen”的 Activity 中的函数。

该代码导致程序崩溃并出现标题中提到的错误。

提前感谢您对此的任何帮助:)

代码如下:

在 TrackingScreen.java 中创建通知的代码

public void updateNotification(){

      boolean firstTime = true;

      NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        nID = 1;     

        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this);


        Intent intent= new Intent(this, TrackingScreen.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_SINGLE_TOP);

        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT);
        mBuilder.setContentIntent(pendingIntent);




        Intent stoptracking = new Intent(TrackingScreen.this, NotificationActivity.class);
        stoptracking.putExtra("notificationId",nID);
        PendingIntent btPendingIntent = PendingIntent.getBroadcast(this, 0, stoptracking,0);


        mBuilder.setSmallIcon(R.drawable.ic_launcher)
        .setContentTitle("MRT Alarm - Tracking Location")
        .setOnlyAlertOnce(true)
        .setWhen(0)
        .addAction(R.drawable.fail, "Stop Tracking", btPendingIntent);

        if (distance < 1500){
            mBuilder.setContentText("Distance Remaining: " + distance + " m");

        }else if (distance > 1500){
            mBuilder.setContentText("Distance Remaining: " + distance/1000 + " km");


        }

        mNotificationManager.notify(nID, mBuilder.build());
    }

TrackingScreen.java中Broadcast Receiver调用的Stop Tracking函数代码

public void stoptracking(){

        TrackingScreen.this.unregisterReceiver(TrackingScreen.this.proximityIntentReceiver);    
        NotificationManager notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.cancel(nID);
        selection = null;
        mUpdater.removeCallbacks(mUpdateView);
        index = 0;
        Intent intent = new Intent();
        setResult(2,intent);
        TrackingScreen.this.finish();       

}

NotificationActivity.java 中广播接收器的代码

public class NotificationActivity extends BroadcastReceiver {




@Override
public void onReceive(Context context, Intent intent) {

    int notificationId = intent.getIntExtra("notificationId", 0);


    TrackingScreen localtrackingscreen = (TrackingScreen)context;
//    localtrackingscreen.stoptracking();


    NotificationManager manager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    manager.cancel(notificationId);
}



}  

list

    <receiver
android:name=".NotificationActivity"
android:enabled="true"
>
</receiver>

LOGCAT

  02-02 16:48:39.277: E/AndroidRuntime(17152): FATAL EXCEPTION: main
02-02 16:48:39.277: E/AndroidRuntime(17152): java.lang.RuntimeException: Unable to start receiver com.androidhive.googleplacesandmaps.NotificationActivity: java.lang.ClassCastException: android.app.ReceiverRestrictedContext cannot be cast to com.androidhive.googleplacesandmaps.TrackingScreen
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.app.ActivityThread.handleReceiver(ActivityThread.java:2495)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.app.ActivityThread.access$1500(ActivityThread.java:150)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1374)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.os.Handler.dispatchMessage(Handler.java:99)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.os.Looper.loop(Looper.java:213)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.app.ActivityThread.main(ActivityThread.java:5225)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at java.lang.reflect.Method.invokeNative(Native Method)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at java.lang.reflect.Method.invoke(Method.java:525)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:741)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:126)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at dalvik.system.NativeStart.main(Native Method)
02-02 16:48:39.277: E/AndroidRuntime(17152): Caused by: java.lang.ClassCastException: android.app.ReceiverRestrictedContext cannot be cast to com.androidhive.googleplacesandmaps.TrackingScreen
02-02 16:48:39.277: E/AndroidRuntime(17152):    at com.androidhive.googleplacesandmaps.NotificationActivity.onReceive(NotificationActivity.java:23)
02-02 16:48:39.277: E/AndroidRuntime(17152):    at android.app.ActivityThread.handleReceiver(ActivityThread.java:2488)
02-02 16:48:39.277: E/AndroidRuntime(17152):    ... 11 more

Answer 1

试试这段代码

public class TrackingScreen extends Activity {

    public static TrackingScreen instance = null;

    public void onCreate(Bundle savedInstanceState) {
        instance = this;
    }
}

并在 onRecieve 函数中:

public void onReceive(Context context, Intent intent) {

    int notificationId = intent.getIntExtra("notificationId", 0);
    TrackingScreen localtrackingscreen = TrackingScreen.instance;
    localtrackingscreen.stoptracking();
    NotificationManager manager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    manager.cancel(notificationId);
}