RecyclerView with SnapHelper, item is not snapped after scrollToPosition

Question

I have a RecyclerView in my activity and a LinearSnapHelper attached to it:

TimePickerAdapter timePickerAdapter = new TimePickerAdapter(hours);
recyclerView = (RecyclerView) root.findViewById(R.id.recycler_view);

final SnapHelper snapHelper = new LinearSnapHelper();
snapHelper.attachToRecyclerView(recyclerView);

The problem is that when I want to initially scroll to a specific item, the snap helper is not being triggered to attach the item (see the image):

recyclerView.getLayoutManager().scrollToPosition(timePickerAdapter.getCurrentPosition());

When I scroll with my hand it starts to work as expected. Any solutions to this?

Answer 1

SnapHelper rely on RecyclerView.OnFlingListener#onFling() or RecyclerView.OnScrollListener#onScrollStateChanged(recyclerView, RecyclerView.SCROLL_STATE_IDLE) to trigger snap action.

But scrollToPosition() will not tigger above callback. You can invoke smoothScrollBy(1, 0) after scrollToPosition() to trigger SnapHelper to scroll.