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Finish all previous activities

My application has the following flow screens :

Home->screen 1->screen 2->screen 3->screen 4->screen 5

Now I have a common log out button in each screens

(Home/ screen 1 / screen 2 /screen 3/ screen 4 / screen 5)

I want that when user clicks on the log out button(from any screen), all the screens will be finished and a new screen Log in will open .

I have tried nearly all FLAG_ACTIVITY to achieve this. I also go through some answers in stackoverflow, but not being able to solve the problem. My application is on Android 1.6 so not being able to use FLAG_ACTIVITY_CLEAR_TASK

Is there any way to solve the issue ?

Do you run your nested activities using startActivityForResult?
no.All the activities are started with startActivity.
I am using nested activities while cod runs finishaffinitytask() in nested activity. does it change the behaviour? as sometimes i am getting Failure delivering result ResultInfo when finishaffinitytask runs.
Please check this answer, It will surely help you stackoverflow.com/a/25159180/2732632
Android 21 introduced Activity.finishAndRemoveTask().

A
Anye

Use:

Intent intent = new Intent(getApplicationContext(), Home.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);

This will clear all the activities on top of home.

Assuming you are finishing the login screen when the user logs in and home is created and afterward all the screens from 1 to 5 on top of that one. The code I posted will return you to home screen finishing all the other activities. You can add an extra in the intent and read that in the home screen activity and finish it also (maybe launch login screen again from there or something).

I am not sure but you can also try going to login with this flag. I don't know how the activities will be ordered in that case. So don't know if it will clear the ones below the screen you are on including the one you are currently on but it's definitely the way to go.


User is showing his first screen as home screen,thats the main issue.
well as i have it my response you need to get back to the home screen and finish that one. so the process call the intent above from any screen. receive the intent on the Home screen and instantly lauch a intent towards login and finish home after the startActivity method. you can also override the pending animation to null for in and out so that it doesn't show the transition ( i do that because it feels kinda quicker).so that should be working fine for the thing you need.
Rather than declare the activity as singleInstance, consider using FLAG_ACTIVITY_CLEAR_TOP|FLAG_ACTIVITY_SINGLE_TOP as the flags for the Intent. This will finish intervening activities and start (or bring back to the foreground) the desired activity.
@ CommonsWare Adding intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_ACTIVITY_SINGLE_TOP); to my activity did not help me.It did not finish the intervening activities.When I press back from the Login screen I can see the previous activities.Here is my code Intent intent=new Intent(BaseActivity.this, Login.class);intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_ACTIVITY_SINGLE_TOP);startActivity(intent);.
this code only clear the top activity stack, for clearing all activities intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | IntentCompat.FLAG_ACTIVITY_CLEAR_TASK);
t
tbraun89

You may try Intent.FLAG_ACTIVITY_CLEAR_TASK|Intent.FLAG_ACTIVITY_NEW_TASK. It will totally clears all previous activity(s) and start new activity.


The proper solution, but only API 11+
I ended up using this extra flag as it doesn't cause a delay when showing the main activity (it won't restart it so it's much faster).
@riwnodennyk why API 11+?
Use IntentCompat.FLAG_ACTIVITY_CLEAR_TASK for pre 11 versions
@ono Yes. That should be all you need. Make sure your target activity's launch mode is set as as "singleTask" in the manifest.
H
Henrique

Before launching your new Activity, simply add the following code:

finishAffinity();

Or if you want it to work in previous versions of Android:

ActivityCompat.finishAffinity(this);

ActivityCompat.finishAffinity(this); calls activity.finish() for api < 16. So it won't work.
@Beto Caldas, I have confirmed the source code myself, it will not work for API < 16 as AamirAbro mentioned. It will just finish the activity that you passing on API < 16.
P
Peter Mortensen

When the user wishes to exit all open activities, they should press a button which loads the first Activity that runs when your application starts, clear all the other activities, then have the last remaining activity finish. Have the following code run when the user presses the exit button. In my case, LoginActivity is the first activity in my program to run.

Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.putExtra("EXIT", true);
startActivity(intent);

The above code clears all the activities except for LoginActivity. Then put the following code inside the LoginActivity's onCreate(...), to listen for when LoginActivity is recreated and the 'EXIT' signal was passed:

if (getIntent().getBooleanExtra("EXIT", false)) {
    finish();  
}

Why is making an exit button in Android so hard?

Android tries hard to discourage you from having an "exit" button in your application, because they want the user to never care about whether or not the programs they use are running in the background or not.

The Android OS developers want your program to be able to survive an unexpected shutdown and power off of the phone, and when the user restarts the program, they pick up right where they left off. So the user can receive a phone call while they use your application, and open maps which requires your application to be freed for more resources.

When the user resumes your application, they pick up right where they left off with no interruption. This exit button is usurping power from the activity manager, potentially causing problems with the automatically managed android program life cycle.


A
AkshayT

I guess I am late but there is simple and short answer. There is a finishAffinity() method in Activity that will finish the current activity and all parent activities, but it works only in Android 4.1 or higher.

For API 16+, use

finishAffinity();

For below 16, use

ActivityCompat.finishAffinity(YourActivity.this);

Hope it helps!


G
Gem
Intent intent = new Intent(this, classObject);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | IntentCompat.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);

This Will work for all Android versions. Where IntentCompat the class added in Android Support library.


IntentCompat.FLAG_ACTIVITY_CLEAR_TASK is not recognised, use Intent instead of IntentCompat.
A
Aristo Michael

Use the following for activity

intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);

remove CLEAR_TASK flag for fragment use.

I hope this may use for some people.


C
Community

On a side note, good to know
This answer works (https://stackoverflow.com/a/13468685/7034327)

Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK|Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
this.finish();

whereas this doesn't work

Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);

.setFlags() replaces any previous flags and doesn't append any new flags while .addFlags() does.

So this will also work

Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);

Great explanation about the difference between setFlag vs addFlag, thank you
K
Kos

From developer.android.com:

public void finishAffinity () Added in API level 16

Finish this activity as well as all activities immediately below it in the current task that have the same affinity. This is typically used when an application can be launched on to another task (such as from an ACTION_VIEW of a content type it understands) and the user has used the up navigation to switch out of the current task and in to its own task. In this case, if the user has navigated down into any other activities of the second application, all of those should be removed from the original task as part of the task switch.

Note that this finish does not allow you to deliver results to the previous activity, and an exception will be thrown if you are trying to do so.


J
Jaydeep purohit

If your application has minimum sdk version 16 then you can use finishAffinity()

Finish this activity as well as all activities immediately below it in the current task that have the same affinity.

This is work for me In Top Payment screen remove all back-stack activits,

@Override
public void onBackPressed() {
         finishAffinity();
        startActivity(new Intent(PaymentDoneActivity.this,Home.class));
    } 

http://developer.android.com/reference/android/app/Activity.html#finishAffinity%28%29


D
Djek-Grif

In my case I use finishAffinity() function in last activity like:

finishAffinity()
startHomeActivity()

Hope it'll be useful.


P
Peter Mortensen

A solution I implemented for this (I think I found it on Stack Overflow somewhere, but I don't remember, so thanks to whoever did that in the first place):

From any of your activities do this:

// Clear your session, remove preferences, etc.
Intent intent  = new Intent(getBaseContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);

Then in your LoginActivity, overwrite onKeyDown:

public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
        moveTaskToBack(true);
        return true;
    }
    return super.onKeyDown(keyCode, event);
}

That's usually a very bad idea, tho it may work, it introduces a point of contact that may break in the future and it will be hard to debug. I'm telling you from experience :)
A
Amrit

For logout button on last screen of app, use this code on logout button listener to finish all open previous activities, and your problem is solved.

{
Intent intent = new Intent(this, loginScreen.class);
ntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
}

P
Prashant Kumar
    Intent i1=new Intent(getApplicationContext(),StartUp_Page.class);
i1.setAction(Intent.ACTION_MAIN);
i1.addCategory(Intent.CATEGORY_HOME);
i1.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
i1.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
i1.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(i1);
finish();

why FLAG_ACTIVITY_CLEAR_TASK twice?
From what I understand, .setFlags replaces the previous flags and does not append any flags. .addFlags is what you wanted to use I presume? Cause all the code above i1.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK); gets wiped out
addFlags Works for me
setFlags will replace all previous, so last setFlags is only valid, previous are replaced. So you don't need to call i1.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); i1.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
A
Adnan Abdollah Zaki

i have same problem you can use IntentCompat , like this :

import android.support.v4.content.IntentCompat;
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK |IntentCompat.FLAG_ACTIVITY_CLEAR_TASK);

this code work for me .

Android api 17


H
Hitesh Kushwah

instead of using finish() just use finishAffinity();


Good answer but requires API 16
H
Husnain Ali

Log in->Home->screen 1->screen 2->screen 3->screen 4->screen 5

on screen 4 (or any other) ->

StartActivity(Log in)
FLAG_ACTIVITY_CLEAR_TOP


When I pressing back button all the previous activities are show in the order they were .those activities need to be closed, when the logout button clicked there will be only one activity in the stack and that will be the login activity.And there is no login screen.User starts from home screen.
K
Kamal Bunkar

for API >= 15 to API 23 simple solution.

 Intent nextScreen = new Intent(currentActivity.this, MainActivity.class);
 nextScreen.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | IntentCompat.FLAG_ACTIVITY_CLEAR_TASK);
 startActivity(nextScreen);
 ActivityCompat.finishAffinity(currentActivity.this);

Elaborate your answer so that everyone can benefit from it.
P
Peter Mortensen

If you are using startActivityForResult() in your previous activities, just override OnActivityResult() and call the finish(); method inside it in all activities.. This will do the job...


No, I am using startActivity only.
It will be difficult to maintain onActivityResult on each activity.I have implemeted DArkO 's suggestion and achieved my goal and thanks for the help.
n
nikki

When user click on the logout button then write the following code:

Intent intent = new Intent(this, LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);

And also when after login if you call new activity do not use finish();


S
Samuel Quiroz

I guess I am late but there is simple and short answer. There is a finishAffinity() method in Activity that will finish the current activity and all parent activities, but it works only in Android 4.1 or higher.

For API 16+, use

finishAffinity();

For below 16, use

ActivityCompat.finishAffinity(YourActivity.this);

Hope it helps!

shareedit answered May 27 '18 at 8:03

Akshay Taru


P
Peter Mortensen

Simply, when you go from the login screen, not when finishing the login screen.

And then in all forward activities, use this for logout:

final Intent intent = new Intent(getBaseContext(), LoginScreen.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
context.startActivity(intent);

It works perfectly.


G
Gabriel Negut

If you log in the user in screen 1 and from there you go to the other screens, use

Intent intent = new Intent(this, Screen1.class);
intent.addFlags(FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);

When I pressing back button all the previous activities are show in the order they were .those activities need to be closed, when the logout button clicked there will be only one activity in the stack and that will be the login activity.
If you want this behavior, you have to override onKeyDown and onBackPressed (or onKeyDown, if you want to support Android versions < 2.0) in each one of your activities (except the login one), and startActivity(login) there as shown above.
I have a button which will take me to the login screen finishing all activities in the stack.Is it possible?
I
ItamarG3

I found this way, it'll clear all history and exit

Intent startMain = new Intent(Intent.ACTION_MAIN);
startMain.addCategory(Intent.CATEGORY_HOME);
startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(startMain);
Intent intent = new Intent(getApplicationContext(), SplashScreen.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);

finish();
System.exit(0);

p
priyankvex

I found this solution to work on every device despite API level (even for < 11)

Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
ComponentName cn = intent.getComponent();
Intent mainIntent = IntentCompat.makeRestartActivityTask(cn);
startActivity(mainIntent);

S
Shivam Tripathi

Best way to close all the previous activities and clear the memory

finishAffinity()
System.exit(0);

M
MosesK

I have tried the flags on my end and still haven't worked. I have an application with a very similar design and I have a possible solution in terms of logic. I have built my Login and Logout using shared preferences.

If I logout, data in my shared preferences is destroyed/deleted.

From any of my activities such as Home.java I check whether shared preferences has data and in this case it won't because I destroyed it when I logged out from one of the screens. Therefore logic destroys/finishes that activity and takes me back to the Login activity. You can replicate this logic in all your other activities.

However remember to perform this check inside onPostResume() because this is what is called when you go back to Home.java

Code Sample Below:

@Override
protected void onPostResume() {
    SharedPreferences pref = this.getSharedPreferences("user_details", Context.MODE_PRIVATE);
    if (pref.getAll().isEmpty()){
        //Shared Preferences has no data.
        //The data has been deleted
        Intent intent = new Intent(getApplicationContext(), Login.class);
        startActivity(intent);
        finish();
        //Finish destroys that activity which in our case is the Home.java
    }


    super.onPostResume();
}

M
Mori

In Kotlin this way:

in Another Activity (with some classes), under Imports

var activity:Activity?=null
    get() = field
    set(value) {
        field = value
    }

Then, under onCreate

activity=this

in MainActivity now:

activity?.finish()