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) {

            }
        });

只需设置viewpage . setcurrentitem (index)和相关的TabLayout将选择各自的选项卡。

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) {

            }
        });