为什么我的Bundle附加功能不存在

Question

我正在构建一个应用程序，并且正在使用FCM通知。当用户点击通知时，我想将他发送到Main Activity上的Fragment1(即片段的名称)。我用intent.putExtra来做这件事，但当我在Main Activity中记录Bundle extras=getIntent().getExtras()时，我有空指针异常。为什么我在putExtra中没有任何东西？

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.fragmentiE/AndroidRuntime:致命异常：mainjava.lang.RuntimeException：无法启动活动组件信息｛com.example.dev3.fragmenti/com.example.def3.fragmenti.MainActivity｝：java.lang.NullPointerException在android.app.ActivityThread.performLaunchActivity(ActivityThreads.java)在android.app.ActivityThread.handleLaunchActivity(ActivityThreads.java)在android.app.ActivityThread.access$700(ActivityThreads.java)在android.app.ActivityThread$H.handleMessage(ActivityThreads.java)在android.os.Handler.dispatchMessage(Handler.java)在android.os.Looper.loop(Looper.java)在android.app.ActivityThread.main(ActivityThreads.java)位于java.lang.reflect.Method.invokeNative(Native Method)位于java.lang.reflect.Method.ioke(Method.java:525)在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java)网址：com.android.internal.os.ZygoteInit.main(ZygoteNit.java)在dalvik.system.NativeStart.main(本地方法)导致原因：java.lang.NullPointerException在com.example.dev3.fragmenti.MainActivity.onCreate(MainActivity.java:53)在android.app.Activity.performCreate(Activity.java)在android.app.Instrumentation.callActivityOnCreate(Instrumentation.java)在android.app.ActivityThread.performLaunchActivity(ActivityThreads.java)在android.app.ActivityThread.handleLaunchActivity(ActivityThreads.java)在android.app.ActivityThread.access$700(ActivityThreads.java)在android.app.ActivityThread$H.handleMessage(ActivityThreads.java)在android.os.Handler.dispatchMessage(Handler.java)在android.os.Looper.loop(Looper.java)在android.app.ActivityThread.main(ActivityThreads.java)位于java.lang.reflect.Method.invokeNative(Native Method)位于java.lang.reflect.Method.ioke(Method.java:525)在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java)网址：com.android.internal.os.ZygoteInit.main(ZygoteNit.java)在dalvik.system.NativeStart.main(本地方法)

Answer 1

On-create仅在活动启动时调用。在收到您的通知时，它主要保持"活动"状态。因此，你应该让你的代码处理额外的：

@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MainActivity(接收新Intent的活动)。如果您的活动已经开始，将调用此操作。

Answer 2

尝试移动

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

高于

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