Android: Finish all activity and take user to home without loading home

Question

There is home icon on app's app bar at top and I want to finish all activities and take user to home page. But, I don't want home page to be re-created.

I have already tried following but it re-creates home page and I don't want it

 fun goToHomePage() {
    val homeIntent = Intent(activity, HomeActivity::class.java)
    homeIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
    startActivity(intent)
 }

    <activity
        android:name="HomeActivity"
        android:screenOrientation="portrait"
        android:theme="@style/AppTheme.NoActionBar"/>

Re-creating home put pressure on our backend and we don't want that. How to do achieve it?

From the documentation for `FLAG_ACTIVITY_CLEAR_TOP`: _"The currently running instance of activity B in the above example will either receive the new intent you are starting here in its onNewIntent() method, or be itself finished and restarted with the new intent. If it has declared its launch mode to be "multiple" (the default) and you have not set FLAG_ACTIVITY_SINGLE_TOP in the same intent, then it will be finished and re-created; for all other launch modes or if FLAG_ACTIVITY_SINGLE_TOP is set then this Intent will be delivered to the current instance's onNewIntent()."_ — Michael, Aug 20 '20 at 17:13

Abhimanyu · Answer 1 · 2020-08-20T17:17:11.777

1

For HomeActivity use "singleTop" launchmode.

In AndroidManifest:

<activity 
    android:launchMode="singleTop"
    android:name="HomeActivity"
    android:screenOrientation="portrait"
    android:theme="@style/AppTheme.NoActionBar" />

Reference: https://developer.android.com/guide/topics/manifest/activity-element#lmode

Edit:

From the docs:

If an instance of the activity already exists at the top of the target task, the system routes the intent to that instance through a call to its onNewIntent() method, rather than creating a new instance of the activity.

Use onNewIntent() to handle your scenario.

edited Aug 20 '20 at 17:17

answered Aug 20 '20 at 17:00

Abhimanyu

11,351
7
51
121

I can't put `singleTop` in AndroidManifest as I need to re-create home sometimes like in the case of user logs-in or log out. – user1288005 Aug 20 '20 at 17:06
Does you app support guest users? – Abhimanyu Aug 20 '20 at 17:08
Okay above implementation works but because I have tabs with fragment in activity. How should I make sure that fragments also don't hit the API when activity's onNewIntent is called? I hit API in fragment's `onViewCreated()`. – user1288005 Aug 20 '20 at 18:32
@user1288005 Please post further questions separately in a new post. – Abhimanyu Aug 20 '20 at 18:53
@user1288005 Comment the link here. Will look into that. – Abhimanyu Aug 20 '20 at 18:54
@user1288005 Please upvote and accept my answer if it works. – Abhimanyu Aug 20 '20 at 18:54

score 0 · Answer 2 · answered Aug 20 '20 at 20:18

To return to the existing instance of HomeActivity, just do this:

val homeIntent = Intent(activity, HomeActivity::class.java)
homeIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP)
startActivity(intent)

This will clear all other activities from the stack back to the existing instance of HomeActivity.

HomeActivity.onNewIntent() will be called.

Android: Finish all activity and take user to home without loading home

2 Answers2