Hi!
There is something in the Android API example FragmentTabs.java
(http://developer.android.com/resources/samples/ApiDemos/src/com/
example/android/apis/app/FragmentTabs.html) that I do not understand.
I will try to explain my problem step-by-step:
First, in the onCreate method of the main activity new actionbar tabs
are added, e.g.:
bar.addTab(bar.newTab()
.setText("Simple")
.setTabListener(new
TabListener<FragmentStack.CountingFragment>(
this, "simple",
FragmentStack.CountingFragment.class)));
The TabListener class used above implements ActionBar.TabListener and
is responsible for creating (add) and managing (attach, detach) the
fragments that are displayed for each tab. Additionally the
TabListener constructor also contains the following code that checks
if a fragment already exists:
// Check to see if we already have a fragment for this
tab, probably
// from a previously saved state. If so, deactivate it,
because our
// initial state is that a tab isn't shown.
mFragment =
mActivity.getFragmentManager().findFragmentByTag(mTag);
if (mFragment != null && !mFragment.isDetached()) {
FragmentTransaction ft =
mActivity.getFragmentManager().beginTransaction();
ft.detach(mFragment);
ft.commit();
}
It turns out that the if statement above is true when the Android
device changes its orientation, so the extra detach for the fragment
has to be executed in this case.
What I do not understand is why a fragment can still exist at that
point. On orientation change the main activity containing all
fragments is destroyed and recreated. I also do not see anything
saving the fragment in a bundle or something. Therefore I would expect
that all fragments are also destroyed when the activity is destroyed
and recreated but this seems to be a wrong assumption. BTW, executing
getBackStackEntryCount() seems to always return zero during program
execution.
Thanks in advance for any help.
Regards,
Anguel
--
You received this message because you are subscribed to the Google
Groups "Android Developers" group.
To post to this group, send email to android-developers@googlegroups.com
To unsubscribe from this group, send email to
android-developers+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=en
