I've encountered the same problem with scrolling fragment to the previous position when returning to it. No scrolling possible in onResume(). I suspect when you post runnable (as you mention in your question) there is no guarantee whether it will work.
I've found 2 solutions, hope this helps:
1) More general approach, still it doesn't work for API level < 11:
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// inflate your main view
mView = inflater.inflate(R.layout.your_fragment_id, container, false);
// find your scroll view
mScrollContainer = (ScrollView) mView.findViewById(R.id.scroll_container);
// add OnLayoutChangeListener
mView.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
@Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
// get your X and Y to scroll to
...
mScrollContainer.scrollTo(x,y);
}
}
});
}
You should get X and Y from your own source (say your own bundle), since in most cases - when activity doesn't save it's state - you just can't use fragment's savedInstanceState (see here)
2) More specific but sometimes more useful method is to set OnFocusChangeListener for the element that gets focus after fragment is shown:
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
...
mListView.setOnFocusChangeListener(new OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus) {
// do your scrolling here
}
});
}