ViewModel is not retained

[leangl]

After screen rotation a new ViewModel is always provided for fragments. Moving the creation of the model from onAttach to onCreate solves the problem.

[mboukadir]

I had the same problem and I am very interested to know the reason why After screen rotation a new ViewModel is always provided for fragment when we create ViewModel in onAttach.

I tried to dig in my side, but I could not find the answer what I noticed is that:
The ViewModels are stored in a ViewModelStore, which is held by HolderFragment.
This HolderFragment is marked as retain a fragment so he must survive to the configuration change and onDestroy() will not be called (but onDetach () still will be, because the fragment is being detached from its current activity).

But in our case onDestroy is called and the ViewModelStore is cleared . as you can see in HolderFragment#onDestory method

@Override
    public void onDestroy() {
        super.onDestroy();
        mViewModelStore.clear();
    }

If my analysis is good the real question is why HolderFragment#onDestroy is called after the configuration change even if he is marked as retain ?

Thank you in advance.