Finish all previous activities

问题:

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 ?

回答1:

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 afterwards 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 activites. 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 its definitely the way to go.

Hope this helps.

回答2:

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.

回答3:

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);

回答4:

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.

回答5:

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.

回答6:

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.

回答7:

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.

回答8:

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

回答9:

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);

回答10:

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);
}

回答11:

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);
}

回答12:

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!

回答13:

    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();

回答14:

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

回答15:

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

on screen 4 (or any other) ->

StartActivity(Log in)

with

FLAG_ACTIVITY_CLEAR_TOP

回答16:

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

回答17:

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...

回答18:

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);

回答19:

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();

回答20:

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);

回答21:

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.

回答22:

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);

回答23:

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

finishAffinity()
startHomeActivity()

Hope it\'ll be useful.

回答24:

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);