android - How to maintain the state of the activity? -

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i trying save state of activity in android.basic scenario there 2 activities , b.activity contains 2 edittext fields.user enters value , moves activity b via intent.when user comes activity (by intent have provided button) need display values in 2 edittext fields user had entered (i.e maintain state of activity a).also not want use shared preferences or make fields static. have used following code not help:

  @override protected void oncreate(bundle savedinstancestate)  {     super.oncreate(savedinstancestate);     setcontentview(r.layout.manual_entry);             edittext1=(edittext)findviewbyid(r.id.edittext1);     }  @override     protected void onsaveinstancestate(bundle savedinstancestate)     {           super.onsaveinstancestate(savedinstancestate);           savedinstancestate.putstring("cardvalue_saved_inst", value_card_manuallyentered);     }     @override     public void onrestoreinstancestate(bundle savedinstancestate)      {       super.onrestoreinstancestate(savedinstancestate);       value_savedinstance = savedinstancestate.getstring("cardvalue_saved_inst");       log.e("value_savedinstance",""+value_savedinstance);       edittext1.settext(value_savedinstance);     }

in activitya, if launch activityb , don't call finish() on yourself, when activityb finishes (when user presses button or otherwise), activitya shown in same state in. standard android behaviour , don't need special.

onrestoreinstancestate() not called if paused activity gets resumed (which usual case activitya launches activityb , activityb finishes).

onrestoreinstancestate() only called if android killed activity (during orientation change example) or killed process. in case, when user returns activity, android create new instance of activity , call onrestoreinstancestate().


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