How do I change the text style of a selected tab when using tabLayout?

Question

I want to make the text of a selected tab bold. How can I do this either through xml or java code, whatever is easier.

Answer 1

There is a way to add bold programmatically by using a Tab CustomView, loading a TextView into that CustomView and applying styling on the TextView:

private TabLayout mTabLayout;
protected void onCreate(Bundle savedInstanceState) {
    ...
    mTabLayout = (TabLayout) findViewById(R.id.tablayout);
    mTabLayout.setOnTabSelectedListener(new OnTabSelectedListener());
    int tabCount = mTabLayout.getTabCount();
    for (int i = 0; i < tabCount; i++) {
        TabLayout.Tab tab = mTabLayout.getTabAt(i);
        if (tab != null) {
            TextView tabTextView =
                (TextView) LayoutInflater.from(this).inflate(R.layout.tab_item, mTabLayout, false);
            tabTextView.setText(tab.getText());
            // First tab is the selected tab, so if i==0 then set Tabs_Selected style
            tabTextView.setTextAppearance(getAppContext(), i == 0 ? R.style.TextAppearance_Tabs_Selected
                                              : R.style.TextAppearance_Tabs);
            tab.setCustomView(tabTextView);
        }
    }
}
class OnTabSelectedListener implements TabLayout.OnTabSelectedListener {

    public void onTabSelected(TabLayout.Tab selectedTab) {
        int tabCount = mTabLayout.getTabCount();
        for (int i = 0; i < tabCount; i++) {
            TabLayout.Tab tab = mTabLayout.getTabAt(i);
            View tabView = tab != null ? tab.getCustomView() : null;
            if (tabView instanceof TextView) {
                ((TextView) tabView).setTextAppearance(getAppContext(), selectedTab.equals(tab)
                                                           ? R.style.TextAppearance_Tabs_Selected
                                                           : R.style.TextAppearance_Tabs);
            }
        }
    }

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

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

And here is the entries in styles.xml:

And here is the layout tab_item: