android - Why onDestroy inActivity A not being called after a call to finish() in ActivityB -

the next process simple understand , reproduce leads bug:

• activitya starts activityb in oncreate() method
• activityb created , call finish() in onresume() method
• activityb ondestroy() called
• activitya onresume() called
• and here in activitya, click menu button call finish() - or press key.
• activitya removed ondestroy() not called , still living ( adb shell dumpsys 'mypackagename' indicates many living activities )

code

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="gleroy.com.algo">      <application         android:allowbackup="true"         android:icon="@mipmap/ic_launcher"         android:label="@string/app_name"         android:theme="@style/apptheme">         <activity             android:name=".activity.mainactivity"             android:label="@string/app_name">             <intent-filter>                 <action android:name="android.intent.action.main" />                  <category android:name="android.intent.category.launcher" />             </intent-filter>         </activity>           <activity             android:name="gleroy.com.algo.activity.fakea"             android:label="@string/app_name"></activity>          <activity             android:name="gleroy.com.algo.activity.fakeb"             android:label="@string/app_name"></activity>     </application> </manifest> 

activity :

public class fakea extends activity {      private final static string tag = fakea.class.getcanonicalname();      @override     protected void oncreate(bundle savedinstancestate) {         log.d(tag, "oncreate, taskid :" + gettaskid());         super.oncreate(savedinstancestate);          intent intent = new intent(fakea.this, fakeb.class);         startactivity(intent);     }      @override     protected void onresume() {         log.d(tag, "onresume");         super.onresume();     }       @override     protected void ondestroy() {         log.d(tag, "ondestroy");         super.ondestroy();     }      @targetapi(build.version_codes.honeycomb)     @override     public boolean oncreateoptionsmenu(menu menu) {         // inflate menu; adds items action bar if present.         getmenuinflater().inflate(r.menu.menu_main, menu);         super.oncreateoptionsmenu(menu);         return true;     }      @override     public boolean onoptionsitemselected(menuitem item) {          switch (item.getitemid()) {             case r.id.stop_session_menu_item:                 /* stop , quit */                 finish();                 return false;         }          return super.onoptionsitemselected(item);     } } 

activity b :

public class fakeb extends activity {      private final static string tag = fakeb.class.getcanonicalname();      @override     protected void oncreate(bundle savedinstancestate) {         log.d(tag, "oncreate, taskid :"+gettaskid());         super.oncreate(savedinstancestate);     }      @override     protected void onresume() {         super.onresume();         log.d(tag, "onresume, isfinishing :" + isfinishing());         finish();     }      @override     protected void ondestroy() {         super.ondestroy();         log.d(tag, "ondestroy");     } } 

activity started mainactivity contains simple button :

 @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);      findviewbyid(r.id.btn).setonclicklistener(new view.onclicklistener() {         @override         public void onclick(view v) {             intent intent = new intent(mainactivity.this, fakea.class);             startactivity(intent);         }     }); 

so know can't sure ondestroy() gonna called here activitya leaking.

also observed if use timer , timertask delay startactivity in activitya or finish() in activityb don't have bug anymore.

here events :

• fakea oncreate, taskid :154
• fakea onresume
• fakea onpause, isfinishing : false
• fakeb oncreate, taskid :154
• fakeb onresume, isfinishing :false
• fakea onresume
• fakeb ondestroy
• call finish or press key : fakea onpause, isfinishing : true

in place of finish() try finishaffinity(). far know: finish() destroys current live activity while, finishaffinity() destroys active activities.