android - Weird Activity Lifecycle. -

android - Weird Activity Lifecycle. -

when first start activity main activity, goes through oncreate() onstart(). while in app, if turn off screen, goes onpause() save data. goes onstop(), ondestroy(), again, without turning on screen oncreate(), onstart(), onpause(). should go oncreate(), onstart() right after ondestroy(), without me doing anything?

@override protected void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); requestwindowfeature(window.feature_no_title); getwindow().setflags(windowmanager.layoutparams.flag_fullscreen, windowmanager.layoutparams.flag_fullscreen); setcontentview(r.layout.activity_timegame); } @override protected void onresume() { super.onstart(); if (checkfirsttimerun()) initializegame(); else resumegame(); } @override protected void onpause() { super.onpause(); savegamedata(); }

shorter explanation(considering not using fragments):

creation of activity oncreate,onstart,onresume when rotate screen onpause,onstop,ondestroy- 1 time again oncreate,onstart,onresumebecause activity destroyed , recreated onorientation change

thus, if won't rotate oncreate,onstart,onresume not fired sec time !

understand events executed , when:

have @ 1 of answers posted in stackoverflow - click here

a utilize case example(considering using fragments):

sample project:

i have opensource project download here , execute , see log understand >the sequence of events executes 1 after another(i have fragment in project exclude >fragment logs if don't need it)

project observations

if path activity-fragmentone , alter orientation first time events fired follows mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume

if path activity-fragmentone-orientationchange , alter orientation first time events fired follows

mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume

if path activity-fragmentone-orientationchange-orientationchange , alter orientation first time events fired follows

mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume

if path activity-fragmentone-orientationchange-orientationchange-fragmenttwo , alter orientation first time events fired follows

mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onstop- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmenttwo-onactivitycreated- fragmentone-onstart- fragmentone-onresume

if path activity-fragmentone-orientationchange-orientationchange-fragmenttwo-orientationchange , alter orientation first time events fired follows

mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmentone-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onstop- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmenttwo-onactivitycreated- fragmentone-onstart- fragmentone-onresume- fragmentone-onpause- fragmentone-onsaveinstancestate- fragmentone-onsaveinstancestate- fragmentone-onstop- fragmentone-ondestroy- fragmentone-ondetach- fragmentone-ondestroy- fragmentone-ondetach- mainactivity-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-onattach- fragmentone-oncreate- fragmentone-oncreateview- fragmenttwo-onactivitycreated- fragmentone-onstart- fragmentone-onresume

android