because the version 1.0.0 has not check the state, so it will not throw the exception,
but the version 1.1.0 changes the source code，so it throws the exception.
this is the Fragment version-1.1.0 source code, it will invoke the method performRestore
void performCreate(Bundle savedInstanceState) {
if (mChildFragmentManager != null) {
mChildFragmentManager.noteStateNotSaved();
}
mState = CREATED;
mCalled = false;
mSavedStateRegistryController.performRestore(savedInstanceState);
onCreate(savedInstanceState);
mIsCreated = true;
if (!mCalled) {
throw new SuperNotCalledException("Fragment " + this
+ " did not call through to super.onCreate()");
}
mLifecycleRegistry.handleLifecycleEvent(Lifecycle.Event.ON_CREATE);
}
/**
the exception
**/
public void performRestore(@Nullable Bundle savedState) {
Lifecycle lifecycle = mOwner.getLifecycle();
if (lifecycle.getCurrentState() != Lifecycle.State.INITIALIZED) {
throw new IllegalStateException("Restarter must be created only during "
+ "owner's initialization stage");
}
lifecycle.addObserver(new Recreator(mOwner));
mRegistry.performRestore(lifecycle, savedState);
}
this is the version-1.0.0 source code，did not invoke the performRestore,so will not throw the exception
void performCreate(Bundle savedInstanceState) {
if (mChildFragmentManager != null) {
mChildFragmentManager.noteStateNotSaved();
}
mState = CREATED;
mCalled = false;
onCreate(savedInstanceState);
mIsCreated = true;
if (!mCalled) {
throw new SuperNotCalledException("Fragment " + this
+ " did not call through to super.onCreate()");
}
mLifecycleRegistry.handleLifecycleEvent(Lifecycle.Event.ON_CREATE);
}
There are two different solution which can handle this:
The first solution is to split the transaction。
Because we always use replace or merge remove and add into one Transaction.
We can split the transaction to two transaction like this:
FragmentTransaction ft = manager.beginTransaction();
Fragment prev = manager.findFragmentByTag(tag);
if (prev != null) {
//commit immediately
ft.remove(prev).commitAllowingStateLoss();
}
FragmentTransaction addTransaction = manager.beginTransaction();
addTransaction.addToBackStack(null);
addTransaction.add(layoutId, fragment,
tag).commitAllowingStateLoss();
because this two transaction will be two different Message which will be handled by Handler.
The second solution is check the state in advance.
we can follow the source code，check the state in advance
FragmentTransaction ft = manager.beginTransaction();
Fragment prev = manager.findFragmentByTag(tag);
if (prev != null) {
if (prev.getLifecycle().getCurrentState() != Lifecycle.State.INITIALIZED) {
return;
}
ft.remove(prev);
}
I recommend the first way,because the second way is folowing the source code,if the source
code change the code, it will be invalid。
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