android - How to keep fragments in memory on orientation change -

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i'm creating tablet optimised application using fragments. have thin navigation fragment down left hand side buttons controls fragments loaded 2 viewgroup containers take rest of screen.

for example, if button in navigation fragment pressed, 1st container loaded item list fragment (eg settings, customers etc) , second container loaded fragment show item details.

since want retain fragments in memory (so, when navigating settings customers , settings, previous settings fragments should there user doesn't lose to) - have created fragments instance variables activity

settingslistfragment settingslistfragment; settingsdetailfragment settingsdetailfragment; customerlistfragment customerlistfragment; customerdetailfragment customerdetailfragment;

i create these fragments when neccessary , replace containers fragments needed. eg.

fragmentmanager fragmentmanager = getfragmentmanager(); fragmenttransaction fragmenttransaction = fragmentmanager.begintransaction(); if(settingslistfragment == null){    settingslistfragment = new settingslistfragment(); }             fragmenttransaction.replace(r.id.fragment_container_left, settingslistfragment); fragmenttransaction.commit();

my question is, how can retain these instances accross orientation change?

i'm assuming shouldn't use activities onretainnonconfigurationinstance() method according http://developer.android.com/resources/articles/faster-screen-orientation-change.html because "be careful object pass through onretainnonconfigurationchange() ...this means should never pass view, drawable, adapter, etc"

i've attempted fragment fragment manager, fragment clf = fragmentmanager.findfragmentbytag("client list"); comes null. think gets released after fragment replaced.

thanks help/advice.

you can't (or shouldn't) retain fragments in way. i'm guessing it's state want keep.

if store state in onsaveinstancestate() can later retrive in oncreate() or onactivitycreate(). after go (you'll have add fragmenttransaction stack) can restore state bundle saved it!

fragmentmanager take care of handling configuration changes , restoring fragments in current views.


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