试试这个方法。

tabLayout.setTabTextColors(getResources().getColor(R.color.colorHintTextLight),
                           getResources().getColor(R.color.colorPrimaryTextLight));

如果碰巧你的默认选项卡是第一个(0)，而你碰巧切换到一个片段，那么你必须手动替换第一次的片段。这是因为在注册侦听器之前选择了选项卡。

private TabLayout mTabLayout;

...

@Override
public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_tablayout, container, false);
    mTabLayout = view.findViewById(R.id.sliding_tabs);
    mTabLayout.addOnTabSelectedListener(mOnTabSelectedListener);

    getActivity().getSupportFragmentManager().beginTransaction()
        .replace(R.id.tabContent, MyFirstFragment.newInstance()).commit();
    return view;
}

或者，你可以考虑调用getTabAt(0).select()并像这样重写onTabReselected:

@Override
public void onTabReselected(TabLayout.Tab tab) {
    // Replace the corresponding tab fragment.
}

这是可行的，因为你实际上是在每个选项卡重新选择上替换片段。

如果你不能使用tab.select()，也不想使用ViewPager，你仍然可以通过编程方式选择一个选项卡。如果你通过TabLayout使用自定义视图。选项卡setCustomView (android.view。View View)它更简单。以下是如何做到这两种方式。

// if you've set a custom view
void updateTabSelection(int position) {
    // get the position of the currently selected tab and set selected to false
    mTabLayout.getTabAt(mTabLayout.getSelectedTabPosition()).getCustomView().setSelected(false);
    // set selected to true on the desired tab
    mTabLayout.getTabAt(position).getCustomView().setSelected(true);
    // move the selection indicator
    mTabLayout.setScrollPosition(position, 0, true);

    // ... your logic to swap out your fragments
}

如果你不使用自定义视图，那么你可以这样做

// if you are not using a custom view
void updateTabSelection(int position) {
    // get a reference to the tabs container view
    LinearLayout ll = (LinearLayout) mTabLayout.getChildAt(0);
    // get the child view at the position of the currently selected tab and set selected to false
    ll.getChildAt(mTabLayout.getSelectedTabPosition()).setSelected(false);
    // get the child view at the new selected position and set selected to true
    ll.getChildAt(position).setSelected(true);
    // move the selection indicator
    mTabLayout.setScrollPosition(position, 0, true);

    // ... your logic to swap out your fragments
}

使用StateListDrawable在选中和未选中的可绘制对象之间切换，或者类似地处理颜色和/或可绘制对象。

我是这样解决的:

void selectPage(int pageIndex){
    tabLayout.setScrollPosition(pageIndex,0f,true);
    viewPager.setCurrentItem(pageIndex);
}

如果你使用TabLayout没有viewPager，这有助于

 mTitles = getResources().getStringArray(R.array.tabItems);
    mIcons = getResources().obtainTypedArray(R.array.tabIcons);
    for (int i = 0; i < mTitles.length; i++) {

        tabs.addTab(tabs.newTab().setText(mTitles[i]).setIcon(mIcons.getDrawable(i)));
        if (i == 0) {
            /*For setting selected position 0 at start*/
            Objects.requireNonNull(Objects.requireNonNull(tabs.getTabAt(i)).getIcon()).setColorFilter(ContextCompat.getColor(getApplicationContext(), R.color.colorPrimary), PorterDuff.Mode.SRC_IN);
        }
    }

    tabs.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
        @Override
        public void onTabSelected(TabLayout.Tab tab) {
            Objects.requireNonNull(tab.getIcon()).setColorFilter(ContextCompat.getColor(getApplicationContext(), R.color.colorPrimary), PorterDuff.Mode.SRC_IN);
        }

        @Override
        public void onTabUnselected(TabLayout.Tab tab) {
            Objects.requireNonNull(tab.getIcon()).setColorFilter(ContextCompat.getColor(getApplicationContext(), R.color.white), PorterDuff.Mode.SRC_IN);
        }

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

        }
    });

你应该使用viewPager来使用viewpage . setcurrentitem ()

 viewPager.setCurrentItem(n);
 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) {

            }
        });