When receiving a Firebase push notification, while the App is backgrounded, Firebase automatically displays a notification.
The pending Intent included in this notification seems to always include the FLAG_ACTIVITY_NEW_TASK flag, which will cause the App to be restarted when the notification is clicked, even if the App is already alive in the background.
Is there any way to prevent this behaviour and simply have onNewIntent(intent) on the main Activity invoked instead?
The launchMode attribute of the activity affects how the activity is launched.
see:
https://developer.android.com/guide/topics/manifest/activity-element.html#lmode
singleTop, singleTask, or singleInstance should be used to prevent the notification intent from creating a new activity instance.
The flag FLAG_ACTIVITY_NEW_TASK doesn't influence a new activity being created, but makes the launched activity the root of a new task.
see:
https://developer.android.com/reference/android/content/Intent.html#FLAG_ACTIVITY_NEW_TASK
and:
https://developer.android.com/guide/components/tasks-and-back-stack.html
Hope this helps.
in AndroidManifest.xml set your Activity launchMode to singleTask should fix this:
<activity
......
android:launchMode="singleTask"
>
Related
I have an activity which is called if the app receives a push notification. The activity is started with FLAG_ACTIVITY_NEW_TASK and FLAG_ACTIVITY_CLEAR_TOP. The activity, let's call it 'A' shows UI and finishes after a while. In this point have a problem with activity stack.
Scenario:
The app is in the background with another activity 'B'
Then the app receives a push notification and starts Activity A.
After related things done, the app finishes Activity A
Then returns to Activity B and stays in the foreground even the app was in the background before the push notification is received.
After debugging, I figured out that the system calls onResume method of Activity B after finishing Activity A.
How can I do the app keep staying in background if the app started from background? Should I change intent flags of the activity A?
In your case you can achieve this in two ways
1- From manifest file with activity tag android:noHistory="true"
2- From code when you are staring the activity set flags like below
Intent mIntent = new Intent(context, Youractivity.class);
mIntent.setFlags(mIntent.getFlags() | Intent.FLAG_ACTIVITY_NO_HISTORY);
startActivity(mIntent);
For more information checkout developers link
One other thing you can do is instead of this.finish() in notificationActivity is to use this.finishAffinity();. This will close the app instead coming to foreground.
My app and activity is in my list of recent apps when I receive a notification. When I click on the notification, I want the intent of the notification to be honored. In my case I want to restart the activity (brute force) and pass in the new intent: so, finish then re-create. I am reading about such tags as FLAG_ACTIVITY_NEW_TASK and FLAG_ACTIVITY_SINGLE_TOP but I don't understand them enough to know how to force a "finish then re-create` of my activity. And, oh, the activity in question is MainActivity.
The snippet inside GcmListenerService uses
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
for sending the notification intent
Alternatively
If I go with onNewIntent things get complicated because there maybe DialogFragments being displayed, etc. And I would have to clear everything. That is why finish then re-create seem like the simplest solution to me.
Intent flag FLAG_ACTIVITY_CLEAR_TOP should produce the desired behavior. The documentation for Tasks and Back Stack says this in the section for Using Intent Flags:
If the launch mode of the designated activity is "standard", it too is
removed from the stack and a new instance is launched in its place to
handle the incoming intent. That's because a new instance is always
created for a new intent when the launch mode is "standard".
The documentation for FLAG_ACTIVITY_CLEAR_TOP describes the same behavior in more detail.
For an App I am developing, I override the back button to make it act like the home button so that the state of the main activity is preserved even when the app is exited. Now, I also send a notification to the user from time to time using a service. When this notification is pressed I want to open the main activity again. I noticed though that this creates a second instance of the app, which creates major problems. I am trying to make the main activity go to the front again, without calling oncreate again like so:
Intent to launch main activity again:
Intent notificationIntent = new Intent(this, MainActivity.class);
notificationIntent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
This doesn't work though. I still end up with two instances of my main activity. Does anybody know how to fix this?
By the way, I already have android:launchMode="singleInstance" in my manifest.
There's a way to force the OS to create only one instance of an activity and thats using the tag launchMode in the Manifest as shown below:
<activity android:name="YourActivity"
android:launchMode="singleInstance"/>
Hope this Helps...
Regards
Try adding this flag to the intent .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP), works for me.
I have just noticed that parameter FLAG_ACTIVITY_SINGLE_TASK is no more available in the Android developer documentation:
I am just trying to do this:
removeCard.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TASK);
startActivity(removeCard);
I have already seen such a parameter in code found in Google but the Java compiler just tells me it does not exist.
I am only able to start the main activity with this parameter but I have to configure the manifest file to perform this:
android:launchMode = "singleTask"
And this does not work for activities other than main activities launched upon app start.
Does someone know why this parameter disappear for Intent ?
Regards,
Franz
Ok so after having a look around, I managed to figure out that there is no such things as FLAG_ACTIVITY_SINGLE_TASK or FLAG_ACTIVITY_SINGLE_INSTANCE, nor has there even been. This is because you are looking for values which can only be defined through the application's launch mode which is defined in the manifest. Only FLAG_ACTIVITY_SINGLE_TOP is available as an intent flag. Therefore if you want to make use of any of the singleTask, singleInstance, singleTop or standard launch modes, they must be defined in the manifest:
<activity
android:name="com.company.ActivityName"
android:launchMode="singleTask">
</activity>
See the launchMode section in the documentation: http://developer.android.com/guide/topics/manifest/activity-element.html
android:launchMode = "singleTask" should work for all activities when used correctly and are you sure you're not referring the FLAG_ACTIVITY_SINGLE_TASK which is still present and appears to do what you are wanting.
public static final int FLAG_ACTIVITY_SINGLE_TOP
Since: API Level 1 If set, the activity will not be launched if it is
already running at the top of the history stack.
No it is not missing. From developer docs......Using Intent flags
FLAG_ACTIVITY_NEW_TASK
Start the activity in a new task. If a task is already running for the activity you are now starting, that task is brought to the foreground with its last state restored and the activity receives the new intent in onNewIntent().
This produces the same behavior as the "singleTask" launchMode value, discussed in the previous section.
That means FLAG_ACTIVITY_NEW_TASK do the same as Singletask do
I know there's been a few posts for what I'm about to ask but I can't find any with the right answer.
From my understanding, if your main activity's (let's call it A) launchMode is set to singleTask, and A has initiated activity B then a click to the home button will destroy the history stack and re-launching the application will take you back to A and not B.
I have launchMode set to singleTask because I have a persistent notification and I don't want to have multiple instances of the main activity to appear whenever the user clicks on the notification.
Is there something I'm missing that would allow me to cater for both?
So I'm asking if there's a way I can ensure that whenever the user wishes to launch the app, from the notification or not, to take him back to the last (current) activity.
If I change launchMode to singleTop it works but I get multiple instances of the main activity whenever I launch it.
Thanks
Andreas
Have you tried setting launchMode to singleTop to all the activities in your app?? Because what i get from your query is that the main activity isn't singleTop, so that might lead to another instance of the main activity being called once the main activity is launched from the activity that was launched from the notification activity.
Or you can specify the launchMode as an attribute to the application tag itself in the manifest.
I use the following code to avoid multiple instances of the activity
Intent intent=new Intent(this,RICO.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_ACTIVITY_SINGLE_TOP);
PendingIntent contentIntent = PendingIntent.getActivity(this, 0, intent, 0);
Changing manifest doesn't look appropriate to me
I'm having issues with both the approches.
The notification works flawless only in this condition:
- using the back button in the main activity (with the history containing only the that activity)
- not using the Home button
- not using the notification IF the activity you are calling is on top and active
In any other case, the notification cannot anymore call on the foreground the activity by using "new Intent(...)"
I've found the alchemical combination of manifest options and intent's flags for getting what I needed:
Intent intent= new Intent(this, YaampActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
using these options
android:launchMode="singleTask"
android:taskAffinity=""
android:excludeFromRecents="true"
inside the element.
Now I've a notification which spawns the main activity (if that activity is not already in the foreground) and its behavior is correct even if the activity is "closed" by pressing the home button and/or the back one.