android - onTabSelected Selected Not Called

Question

I have just migrated my old ActionBar to new TabLayout ( Support Material Design ).

Everything is great but I can't intercept tab selection The method onTabSelected is only called the first time TabLayout is displayed, but when clicking tabs, nothing happens! Any idea what's wrong with this code?

 tabLayout = (TabLayout) findViewById(R.id.tabs);
    tabLayout.setTabMode(TabLayout.MODE_SCROLLABLE);
    mViewPager = (ViewPager) findViewById(R.id.pager);
    if (mViewPager != null) {
        setupViewPager();
    }
    tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
        @Override
        public void onTabSelected(TabLayout.Tab tab) {

            numTab = tab.getPosition();
            prefs.edit().putInt("numTab", numTab).apply();

        }

        @Override
        public void onTabUnselected(TabLayout.Tab tab) {

        }

        @Override
        public void onTabReselected(TabLayout.Tab tab) {

        }
    });

    tabLayout.setupWithViewPager(mViewPager);

Answer 1

When you call setupWithViewPager, this will internally call setOnTabSelectedListener(new ViewPagerOnTabSelectedListener(viewPager));, overriding your OnTabSelectedListener.

Instead, your listener should extend TabLayout.ViewPagerOnTabSelectedListener, then override onTabSelected() and call setOnTabSelectedListener() after setupWithViewPager():

tabLayout.setupWithViewPager(mViewPager);
tabLayout.setOnTabSelectedListener(
  new TabLayout.ViewPagerOnTabSelectedListener(mViewPager) {
    @Override
    public void onTabSelected(TabLayout.Tab tab) {
        super.onTabSelected(tab);
        numTab = tab.getPosition();
        prefs.edit().putInt("numTab", numTab).apply();
    }
});