android - TabLayout tabs text not displaying

Question

I am using TabLayout inside a Fragment to display three fixed tabs and the tabs are working but it doesn't show the tab text even after I set the app:tabTextColor attribute in the layout it's still not visible.

NewFragment.java

public class NewFragment extends Fragment {

private RecyclerView mRecyclerView;
private RecyclerView.LayoutManager mLayoutManager;
private RecyclerView.Adapter mAdapter;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    View inflatedView = inflater.inflate(R.layout.new_fragment, container, false);

    TabLayout tabLayout = (TabLayout) inflatedView.findViewById(R.id.tabLayout);
    tabLayout.addTab(tabLayout.newTab().setText("Tab 1"));
    tabLayout.addTab(tabLayout.newTab().setText("Tab 2"));
    tabLayout.addTab(tabLayout.newTab().setText("Tab 3"));
    final ViewPager viewPager = (ViewPager) inflatedView.findViewById(R.id.viewpager);

    LinearLayoutManager mLayoutManager = new LinearLayoutManager(getActivity());
    mLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);

    viewPager.setAdapter(new PagerAdapter(getFragmentManager(), tabLayout.getTabCount()));
    viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
    tabLayout.setupWithViewPager(viewPager);
    tabLayout.setTabMode(TabLayout.MODE_FIXED);
    tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {

        @Override
        public void onTabSelected(TabLayout.Tab tab) {
            viewPager.setCurrentItem(tab.getPosition());
        }

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

        }

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

        }
    });

    return inflatedView;
}

public class PagerAdapter extends FragmentStatePagerAdapter {
    int mNumOfTabs;

    public PagerAdapter(FragmentManager fm, int NumOfTabs) {
        super(fm);
        this.mNumOfTabs = NumOfTabs;
    }

    @Override
    public Fragment getItem(int position) {

        switch (position) {
            case 0:
                return new FragmentTab();
            case 1:
                return new FragmentTab();
            case 2:
                return new FragmentTab();
            default:
                return null;
        }
    }

    @Override
    public int getCount() {
        return mNumOfTabs;
    }
}
}

newfragment.xml

<android.support.design.widget.AppBarLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context=".NewFragment">

<android.support.design.widget.TabLayout
    android:id="@+id/tabLayout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:tabMode="fixed"
    app:tabTextColor="#ffffff"
    app:tabGravity="fill"
    app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"/>

<android.support.v4.view.ViewPager
    android:id="@+id/viewpager"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@android:color/white"/>

</android.support.design.widget.AppBarLayout>

Answer 1

The problem is you're calling setupWithViewPager() after setting up your tabs with the addTab() calls, effectively overwriting them.

From the documentation of TabLayout regarding setupWithViewPager():

The tabs displayed in this layout will be populated from the ViewPager adapter's page titles.

If you would like to use your TabLayout with a ViewPager, you should override getPageTitle() in your PagerAdapter (and remove the addTab() calls, they are redundant).

For example:

public class ExamplePagerAdapter extends FragmentStatePagerAdapter {

    // tab titles
    private String[] tabTitles = new String[]{"Tab1", "Tab2", "Tab3"};

    public ExamplePagerAdapter(FragmentManager fm) {
        super(fm);
    }

    // overriding getPageTitle()
    @Override
    public CharSequence getPageTitle(int position) {
        return tabTitles[position];
    }

    @Override
    public Fragment getItem(int position) {
        switch (position) {
            case 0:
                return new Tab1Fragment();
            case 1:
                return new Tab2Fragment();
            case 2:
                return new Tab3Fragment();
            default:
                throw new RuntimeException("Invalid tab position");
        }
    }

    @Override
    public int getCount() {
        return tabTitles.length;
    }

    // ...
}