Android ListView scrolling to top
AndroidListviewAndroid Problem Overview
I have a ListView
with custom rows. When any of these rows is
clicked, the ListView's data is regenerated. I'd like the list to
scroll back to the top when this happens.
I initially tried using setSelection(0)
in each row's OnClickListener
to achieve this but was unsuccessful (I believe because the ListView
loses its scroll position when its data is invalidated - so my call to
setSelection is undone. I still don't understand how the ListView
decides where to scroll to after invalidation, though).
The only working solution I know of was given by Romain Guy here: http://groups.google.com/group/android-developers/browse_thread/thread/127ca57414035301
It involves (View.post
)ing the call to _listView.setSelection(0)
. I
found this to perform quite poorly.
The newly generated list shows up with its scroll location unchanged
and there is a considerable delay before it scrolls back to the top.
Is there any better way to achieve this functionality?
Any help would be much appreciated.
Thanks!
Android Solutions
Solution 1 - Android
call listView.setSelectionAfterHeaderView();
to scroll to top
Solution 2 - Android
I have tried lot but this one worked for me
list.smoothScrollToPosition(0);
Solution 3 - Android
I simply use listview.setSelection(0);
Works fine for me.
Solution 4 - Android
If you need instant scroll just after ListView
adapter's data was changed, pay attention that it might not be yet populated. In this case you should post()
your setSelection()
or setSelectionAfterHeaderView()
via Handler
so it will be called later in the queue.
listView.Handler.post(new Runnable() {
@Override
public void run() {
listView.setSelectionAfterHeaderView();
}
});
This worked for me.
Solution 5 - Android
Personally, I recommend you find a different UI pattern. It is possible that users will find your current "click, and the list changes in situ" approach intuitive, but I am skeptical.
You could try subclassing ListView
and overriding layoutChildren()
to chain to the superclass, then call setSelection(0)
in the case where that is needed. If the "considerable delay" is due to just the post()
call, this should clear it up.
Solution 6 - Android
as a workaround, you can create a new adapter containing the new regenerated data, then call ListView.setAdapter. after that call ListView.setSelection(n).
btw, the solution provided by commonsware is worked.
Solution 7 - Android
On some different requirement. If you want to scroll up just like while chatting.
mListView.smoothScrollToPosition(mAdapter.getCount());
Solution 8 - Android
This one worked fine when you want to focus the edittext from listview header
listview.setSelectionFromTop(0,0);
If you want to select the particular index view from listview then
listview.setSelection(index); // o for top