public class CustomBottomNavigationBar extends FrameLayout {
// These would be names and associated positions of the tabs specific to your app
    public static final int POSITION_HOME_TAB = 0;
    public static final int POSITION_UPDATES_TAB = 2;
    public static final int POSITION_FINISHED_STORIES_TAB = 1;
    public static final int POSITION_BOOKMARKS_TAB = 3;
    public static final int POSITION_PROFILE_TAB = 4;
// Passed in from the activities using this, in the setter below
    private OnTabSelectionListener mTabSelectionListener;
// For some first-time arrangements of the layout    
    private boolean drawn;
    private LayoutBottomBarBinding binding;
// To store resource ids of the drawable for the icons, the order of tabs above should be the same
    private Integer[] tabResId;
// Used in initial layout
    private boolean shadowDrawn;

    public CustomBottomNavigationBar(Context context) {
        super(context);
        initLayout(context);
    }

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

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

    public CustomBottomNavigationBar(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        initLayout(context);
    }

    private void initLayout(Context context) {
        LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        binding = DataBindingUtil.inflate(layoutInflater, R.layout.layout_bottom_bar, this, true);

        tabResId = new Integer[]{R.id.home_tab_btn, R.id.leaderboard_tab_btn, R.id.activity_tab_btn,
                R.id.bookmarks_tab_btn, R.id.profile_tab_btn};
        binding.homeTabBtn.setOnClickListener(new InternalTabSelectionListener(POSITION_HOME_TAB));
        binding.activityTabBtn.setOnClickListener(new InternalTabSelectionListener(POSITION_UPDATES_TAB));
        binding.leaderboardTabBtn.setOnClickListener(new InternalTabSelectionListener(POSITION_FINISHED_STORIES_TAB));
        binding.bookmarksTabBtn.setOnClickListener(new InternalTabSelectionListener(POSITION_BOOKMARKS_TAB));
        binding.profileTabBtn.setOnClickListener(new InternalTabSelectionListener(POSITION_PROFILE_TAB));

        setWillNotDraw(false);

        setClipToPadding(false);
        setClipToOutline(false);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if (!drawn) {
            drawn = true;
            Rect rect = new Rect();
            ((View) getParent()).getGlobalVisibleRect(rect);
            setY(rect.bottom - rect.top - getContext().getResources().getDimension(R.dimen.bottom_bar_with_shadow_height));
            invalidate();
        } else if (!shadowDrawn) {
            shadowDrawn = true;
            binding.shadowGradient.draw(canvas);
        }
    }

    public int getBottomBarHeight() {
        return binding.bottomBarLayout.getHeight();
    }

    public void setOnTabSelectionListener(OnTabSelectionListener tabSelectionListener) {
        this.mTabSelectionListener = tabSelectionListener;
    }

    public void setSelectedTab(int position) {
        binding.bottomBarLayout.check(tabResId[position]);
    }

    public interface OnTabSelectionListener {
        void onTabSelected(int position);
    }

    private class InternalTabSelectionListener implements OnClickListener {
        private final int mCurrentPosition;

        public InternalTabSelectionListener(int currentTabPosition) {
            mCurrentPosition = currentTabPosition;
        }

        @Override
        public void onClick(View view) {
            if (mTabSelectionListener != null) {
                mTabSelectionListener.onTabSelected(mCurrentPosition);
            }
        }
    }
}