为什么我的 Bundle extras 不存在？

Question

我正在构建一个应用程序并且正在使用 FCM 通知。当用户单击通知时，我想将他发送到 Main Activity 上的 Fragment1（即片段的名称）。我用 intent.putExtra 这样做但是在 Main Activity 中我记录 Bundle extras=getIntent().getExtras() 我有空指针异常。为什么我在 putExtra 里什么都没有？

这是 myFireBaseMessagingService

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    Log.d("OnMessage", "Received");
    super.onMessageReceived(remoteMessage);
    Log.d(TAG, "From " + remoteMessage.getFrom());
    Log.d(TAG, "Body " + remoteMessage.getNotification().getBody());
    sendNotification(remoteMessage);

}




private void sendNotification(RemoteMessage remoteMessage) {
    Intent intent=new Intent(this, MainActivity.class);
    intent.putExtra("action", "goToFragment1");
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    PendingIntent pendingIntent=PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);
    Uri defaultSoundUri=RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder=new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.logo)
            .setContentText(remoteMessage.getNotification().getBody())
            .setContentTitle("Asp")
            .setAutoCancel(true)
            .setSound(defaultSoundUri)
            .setContentIntent(pendingIntent);
    NotificationManager notificationManager=(NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
    notificationManager.notify(0, notificationBuilder.build());


}

这里是 MainActivity

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    btn1=(Button)findViewById(R.id.dugme1);
    btn2=(Button)findViewById(R.id.dugme2);
    btn3=(Button)findViewById(R.id.dugme3);
    dugme=(Button)findViewById(R.id.subscribe);
    dugme.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            FirebaseMessaging.getInstance().subscribeToTopic("developeri");
            Log.d("Bravo", "Subscribed to developeri!");
        }
    });


    FragmentManager fm=getSupportFragmentManager();
    FragmentTransaction ft=fm.beginTransaction();
    StartFragment startFragment=new StartFragment();
    ft.add(R.id.myFragment, startFragment);
    ft.commit();
    btn1.setOnClickListener(btnOnClickListener);
    btn2.setOnClickListener(btnOnClickListener);
    btn3.setOnClickListener(btnOnClickListener);
    Intent intent=getIntent();
    Bundle extras=getIntent().getExtras();
    Log.d("Bundle", "Bundle is here");
    Log.d("Extras", extras.getString("action"));
    if (extras!=null && extras.containsKey("action") && extras.getString("action").contains("goToFragment1")){
        getSupportFragmentManager().beginTransaction().replace(R.id.myFragment, new Fragment1()).commit();
        Log.d("MainActivity", "IF IS HERE");

    }

}
 Button.OnClickListener  btnOnClickListener= new Button.OnClickListener() {
     @Override
     public void onClick(View view) {
         Fragment newFragment;
         if (view==btn1){
             newFragment =new Fragment1();

         }else if(view==btn2){
              newFragment =new Fragment2();
         }else if (view==btn3){
             newFragment =new Fragment3();
         }else{
             newFragment=new StartFragment();
         }
         FragmentTransaction transaction=getSupportFragmentManager().beginTransaction();
         transaction.replace(R.id.myFragment, newFragment);
         transaction.addToBackStack(null);
         transaction.setTransition(FragmentTransaction.TRANSIT_NONE);
         transaction.commit();


     }
 };

}

我的logcat

06-07 09:22:49.598 23913-23913/com.example.dev3.fragmenti E/AndroidRuntime: FATAL EXCEPTION: main java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.dev3.fragmenti/com.example.dev3.fragmenti.MainActivity}: java.lang.NullPointerException at android.app.ActivityThread.performLaunchActivity(ActivityThread.java) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java) at android.app.ActivityThread.access0(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java) at android.os.Handler.dispatchMessage(Handler.java) at android.os.Looper.loop(Looper.java) at android.app.ActivityThread.main(ActivityThread.java) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:525) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.NullPointerException at com.example.dev3.fragmenti.MainActivity.onCreate(MainActivity.java:53) at android.app.Activity.performCreate(Activity.java) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java) at android.app.ActivityThread.access0(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java) at android.os.Handler.dispatchMessage(Handler.java) at android.os.Looper.loop(Looper.java) at android.app.ActivityThread.main(ActivityThread.java) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:525) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java) at dalvik.system.NativeStart.main(Native Method)

Answer 1

On create 仅在 activity 启动时调用。收到您的通知时，它主要保持 "alive"。因此，您应该让您的代码处理额外的内容：

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);

        if (intent.hasExtra("action")) {
            String action =  intent.getExtras().getString("action");
            // Do what ever is needed
            if (action.equalsIgnoreCase("gotToFragment1")) { 
                getSupportFragmentManager().beginTransaction().replace(R.id.myFragment, new Fragment1()).commit();
            }
        }
    }

将 onNewIntent() 方法添加到您的 MainActivity（activity 接收新的 Intent）。如果您的 activity 已经启动，这将被调用。

Answer 2

试着移动你的

    intent.putExtra("action", "goToFragment1");

以上

PendingIntent pendingIntent=PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);

为什么我的 Bundle extras 不存在？

Why my Bundle extras does not exist?

android

bundle

push-notification

android-intent

firebase