TabLayout scrolls to unkown position after calling notifyDataSetChanged on PagerAdapter

Question

I have sample project with TabLayout and PagerAdapter. Strange things happens with TabLayout when I call pagerAdapter.notifyDataSetChanged();

Answer 1

I just added notifyDataSetChanged method inside of TabLayout implementation of Rasi.

It works for me.

public class CustomTabLayout extends TabLayout {

/*
   * Variable to store invalid position.
   */
private static final int INVALID_TAB_POS = -1;

/*
* Variable to store last selected position, init it with invalid tab position.
*/
private int mLastSelectedTabPosition = INVALID_TAB_POS;

public CustomTabLayout(Context context) {
    super(context);
}

public CustomTabLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public CustomTabLayout(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
}

@Override
public void removeAllTabs() {
    // Retain last selected position before removing all tabs
    mLastSelectedTabPosition = getSelectedTabPosition();
    super.removeAllTabs();
}

@Override
public int getSelectedTabPosition() {
    // Override selected tab position to return your last selected tab position
    final int selectedTabPositionAtParent = super.getSelectedTabPosition();
    return selectedTabPositionAtParent == INVALID_TAB_POS ?
            mLastSelectedTabPosition : selectedTabPositionAtParent;
}

public void notifyDataSetChanged() {
    post(new Runnable() {
        @Override
        public void run() {
            TabLayout.Tab selectedTab = getTabAt(getSelectedTabPosition());
            if (selectedTab != null) {
                selectedTab.select();
            }
        }
    });
}
}

and to notify call

mPagerAdapter.notifyDataSetChanged();
mCustomTabLayout.notifyDataSetChanged();