java - class life cycle with ActionBar Sherlock Tab fragments -

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i'm working on 1 of first android applications , got stuck understanding of how controllers/classes lifecycle arranged. i'm coming ios background.

basicly did following simple tutorial

so understand bind tablistener fragment. when switching tabs tablistener's ontabselected() gets called , each time new instance of fragmenta/fragment b created.

that leads fact every time switch tabs oncreate..() methods called again.

i don't want create new fragment instance every time switch tabs rather use 1 created intially @ application start.

the question how can switch tabs without killing fragments in there?

you can achieve attaching/detaching fragments, on tab listener every time tab unselected detach current fragment , on ontabselected method check if have created fragment before.

private fragment       mfragment; private final string   mtag; private final class<t> mclass;  public tablistener(string ptag, class<t> pclass) {     mtag = ptag;     mclass = pclass; }  @override public void ontabselected(tab tab, fragmenttransaction ft) {     if ( mfragment == null ) {         try {             mfragment = (fragment)mclass.newinstance();         } catch (instantiationexception e) {             e.printstacktrace();         } catch (illegalaccessexception e) {             e.printstacktrace();         }         ft.add(r.id.fragment_container,mfragment,mtag);     } else {         ft.attach(mfragment);     }    }  @override public void ontabunselected(tab tab, fragmenttransaction ft) {      if ( mfragment != null ) {         ft.detach(mfragment);     } }     public void ontabreselected(tab tab, fragmenttransaction ft) {     //nothing       }

then can instantiate listener in

tablistener l = new tablistener<myfragment>(tabtag, myfragment.class)

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