Android Clear Activity Stack

Question

I m having several activities in my application  and flow is very complicated  When I click the Logout application navigates to login Screen and from there user can exit by cancel button  calling system exit 0     when I exit or back button  the system invokes an activity from stack    how can I clear all the activities in the stack when I reach Login screen  calling finish   is not practical as there are so many activities and some activities should no be closed when they are active such as native camera invoking activity   validateuser logoutuser   new validateuser    logoutuser logOut    Intent loginscreen   new Intent homepage this  Login2 class    homepage this  finish    loginscreen setFlags  Intent FLAG ACTIVITY CLEAR TOP   Intent FLAG ACTIVITY NO HISTORY   startActivity loginscreen

User · Answer

Clear Activity Backstate by below code   Intent intent   new Intent Your Current Activity this  Your Destination Activity class   intent setFlags Intent FLAG ACTIVITY NEW TASK   Intent FLAG ACTIVITY CLEAR TASK  Intent FLAG ACTIVITY CLEAR TOP   startActivity intent     Done

User · Answer

In my case  LoginActivity was closed as well  As a result    Intent FLAG ACTIVITY CLEAR TOP   Intent FLAG ACTIVITY CLEAR TASK   did not help   However  setting   Intent FLAG ACTIVITY NEW TASK   helped me

User · Answer

Here is a simple helper method for starting a new activity as the new top activity which works from API level 4 up until the current version 17   static void startNewMainActivity Activity currentActivity  Class lt   extends Activity gt  newTopActivityClass        Intent intent   new Intent currentActivity  newTopActivityClass       intent addFlags Intent FLAG ACTIVITY CLEAR TOP       intent addFlags Intent FLAG ACTIVITY NEW TASK       if  Build VERSION SDK INT  gt   Build VERSION CODES HONEYCOMB          intent addFlags 0x8000      equal to Intent FLAG ACTIVITY CLEAR TASK which is only available from API level 11     currentActivity startActivity intent       call it like this from your current activity   startNewMainActivity this  MainActivity class

User · Answer

Using Kotlin   You can set the flag directly using setter method  In Kotlin or is the replacement for the Java bitwise or     intent flags   FLAG ACTIVITY NEW TASK or FLAG ACTIVITY CLEAR TASK   If you plan to use this regularly  create an Intent extension function  fun Intent clearStack         flags   Intent FLAG ACTIVITY NEW TASK or Intent FLAG ACTIVITY CLEAR TASK     You can then directly call this function before starting the intent  intent clearStack

User · Answer

Intent intent   new Intent LoginActivity this MainActivity class                  intent setFlags Intent FLAG ACTIVITY NEW TASK   Intent FLAG ACTIVITY CLEAR TASK   startActivity intent   finish

User · Answer

For Xamarin Developers  you can use   intent SetFlags ActivityFlags NewTask   ActivityFlags ClearTask

User · Answer

When you call startActivity on the last activity you could always use      Intent FLAG ACTIVITY CLEAR TOP   as a flag on that intent    Read more about the flag here

User · Answer

Intent intent   new Intent LoginActivity this  Home class   intent setFlags Intent FLAG ACTIVITY CLEAR TOP      It is use to finish current activity startActivity intent   this finish

User · Answer

I noted that you asked for a solution that does not rely on finish    but I wonder if this may help nonetheless    I tracked whether an exit flag is raised with a static class variable  which survives the entire app lifespan  In each relevant activity s onResume    use   Override public void onResume         super onResume        if  ExitHelper isExitFlagRaised            this finish              The ExitHelper class  public class ExitHelper       public static boolean isExitFlagRaised   false      Let s say in mainActivity  a user presses a button to exit - you can set ExitHelper isExitFlagRaised   true  and then finish    Thereafter  other relevant activities that are resumed automatically will be finished as well

User · Answer

Most of you are wrong  If you want to close existing activity stack regardless of what s in there and create new root  correct set of flags is the following   intent setFlags Intent FLAG ACTIVITY NEW TASK   Intent FLAG ACTIVITY CLEAR TASK     From the doc      public static final int FLAG ACTIVITY CLEAR TASK   Added in API level 11       If set in an Intent passed to   Context startActivity    this flag will cause any existing task that   would be associated with the activity to be cleared before the   activity is started  That is  the activity becomes the new root of an   otherwise empty task  and any old activities are finished  This can   only be used in conjunction with FLAG ACTIVITY NEW TASK

User · Answer

This decision works fine    intent setFlags Intent FLAG ACTIVITY NEW TASK   Intent FLAG ACTIVITY CLEAR TASK     But new activity launch long and you see white screen some time  If this is critical then use this workaround   public class BaseActivity extends AppCompatActivity        private static final String ACTION FINISH    action finish        private BroadcastReceiver finisBroadcastReceiver        Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState            registerReceiver finisBroadcastReceiver   new BroadcastReceiver                  Override             public void onReceive Context context  Intent intent                    finish                             new IntentFilter ACTION FINISH               public void clearBackStack             sendBroadcast new Intent ACTION FINISH                Override     protected void onDestroy             unregisterReceiver finisBroadcastReceiver           super onDestroy              How use it   public class ActivityA extends BaseActivity           Click any button     public void startActivityB             startActivity new Intent this  ActivityB class            clearBackStack              Disadvantage  all activities that must be closed on the stack must extends BaseActivity

[android] Android: Clear Activity Stack

Examples related to android

Examples related to android-activity

Examples related to stack