message: Removed dataSetObserver so only one around
diff: @@ -20,6 +20,7 @@ public class TabNavigationView extends BottomNavigationView implements TabView {
  int selectedTintColor;
  int unselectedTintColor;
  ViewPager.OnPageChangeListener pageChangeListener;
  + DataSetObserver dataSetObserver;
  public TabNavigationView(Context context) {
  super(context);
  @@ -75,13 +76,16 @@ public class TabNavigationView extends BottomNavigationView implements TabView {
  }
  };
  viewPager.addOnPageChangeListener(pageChangeListener);
  - pagerAdapter.registerDataSetObserver(new DataSetObserver() {
  + if (dataSetObserver != null)
  + pagerAdapter.unregisterDataSetObserver(dataSetObserver);
  + dataSetObserver = new DataSetObserver() {
  @Override
  public void onChanged() {
  buildMenu(pagerAdapter);
  setSelectedItemId(viewPager.getCurrentItem());
  }
  - });
  + };
  + pagerAdapter.registerDataSetObserver(dataSetObserver);
  }
  }
  