Question

知道错误的原因（请参阅下面的堆栈跟踪）以及如何解决它？

在我的Activity类中，我有这些。它永远不会进入onReceive方法..为什么？

private UpdateResultReceiver mUpdateResultReceiver;

@Override
    protected void onCreate(Bundle savedInstanceState) {
      //other stuff...
      registerReceiver();
    }

    @Override
    protected void onResume() {
        super.onResume();

        // Register BroadcastReceiver
        registerReceiver();
    }

    @Override
    protected void onPause() {
        super.onPause();

        // Unregister BroadcastReceiver
        unregisterReceiver();
    }

    /**
     * Register a BroadcastReceiver that receives a result 
     * from the services
     */
    private void registerReceiver() {

        // Create an Intent filter that handles Intents from the services
        IntentFilter intentFilter =
            new IntentFilter(UpdateService1.ACTION_1);
        intentFilter.addCategory(Intent.CATEGORY_DEFAULT);
        intentFilter.addAction(UpdateService2.ACTION_2);

        // Register the BroadcastReceiver.
        LocalBroadcastManager.getInstance(this)
           .registerReceiver(mUpdateResultReceiver,
                             intentFilter);
    }

    /**
     * Unregister the receivers
     */
    private void unregisterReceiver() {
        LocalBroadcastManager.getInstance(this)
            .unregisterReceiver(mUpdateResultReceiver);
    }

    /**
     * The Broadcast Receiver that registers itself to receive result
     * from UploadVideoService.
     */
    private class UpdateResultReceiver 
            extends BroadcastReceiver {
        /**
         * Hook method that's dispatched when the UploadService has
         * uploaded the Video.
         */
        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(UpdateService1.ACTION_1)) {
                mFragment1.getProfileInfo();
                ViewUtils.showToast(getApplicationContext(), "updated profile");
            } else if(intent.getAction().equals(UpdateService2.ACTION_2)) {
                mFragment2.getApptList();
                ViewUtils.showToast(getApplicationContext(), "updated appts");
            }
        }
    }

在我的UpdateService1类中，我已调试直到sendBroadcast方法并且程序崩溃：

private void sendBroadcast（）{ //使用LocalBroadcastManager限制此范围 //对VideoUploadClient应用程序的意图。 LocalBroadcastManager.getInstance（本） .sendBroadcast（新意图（ACTION_1） .addCategory（Intent.CATEGORY_DEFAULT））; }

错误堆栈跟踪：

11-01 19:22:09.041: E/AndroidRuntime(26763): java.lang.NullPointerException: Attempt to invoke virtual method 'void android.content.BroadcastReceiver.onReceive(android.content.Context, android.content.Intent)' on a null object reference
11-01 19:22:09.041: E/AndroidRuntime(26763):    at android.support.v4.content.LocalBroadcastManager.executePendingBroadcasts(LocalBroadcastManager.java:297)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at android.support.v4.content.LocalBroadcastManager.access$000(LocalBroadcastManager.java:46)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at android.support.v4.content.LocalBroadcastManager$1.handleMessage(LocalBroadcastManager.java:116)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at android.os.Handler.dispatchMessage(Handler.java:102)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at android.os.Looper.loop(Looper.java:145)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at android.app.ActivityThread.main(ActivityThread.java:5942)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at java.lang.reflect.Method.invoke(Native Method)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at java.lang.reflect.Method.invoke(Method.java:372)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400)
11-01 19:22:09.041: E/AndroidRuntime(26763):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195)

错误：尝试调用虚方法＆＃39; void BroadcastReceiver.onReceiver（...）＆＃39;在null对象引用上

0 个答案: