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

您可以使用以下函数设置TabLayout位置

public void setTab(){
 tabLayout.setScrollPosition(YOUR_SCROLL_INDEX,0,true);
 tabLayout.setSelected(true);
}

我使用TabLayout切换片段。它在大多数情况下都是有效的，除了当我试图以编程方式使用tab.select()，我的TabLayout选择一个选项卡时。OnTabSelectedListener将触发onTabSelected(TabLayout。Tab Tab)，这会让我很伤心。我正在寻找一种不触发侦听器的方法来做程序化选择。

So I adapted @kenodoggy 's answer to my use. I was further facing a problem where some of the internal objects would return null (because they weren't created yet, because I was answering onActivityResult() from my fragment, which occurs before onCreate() in the case the activity is singleTask or singleInstance) so I wrote up a detailed if/else sequence which would report the error and fall through without the NullPointerException that would otherwise trigger. I use Timber for logging, if you're not using that substitute with Log.e().

void updateSelectedTabTo(int position) {
    if (tabLayout != null){
        int selected = tabLayout.getSelectedTabPosition();
        if (selected != -1){
            TabLayout.Tab oldTab = tabLayout.getTabAt(0);
            if (oldTab != null){
                View view = oldTab.getCustomView();
                if (view != null){
                    view.setSelected(false);
                }
                else {
                    Timber.e("oldTab customView is null");
                }
            }
            else {
                Timber.e("oldTab is null");
            }
        }
        else {
            Timber.e("selected is -1");
        }
        TabLayout.Tab newTab = tabLayout.getTabAt(position);
        if (newTab != null){
            View view = newTab.getCustomView();
            if (view != null){
                view.setSelected(false);
            }
            else {
                Timber.e("newTab customView is null");
            }
        }
        else {
            Timber.e("newTab is null");
        }
    }
    else {
        Timber.e("tablayout is null");
    }
}

这里，tabLayout是绑定到XML中的tabLayout对象的内存变量。我不使用滚动标签功能，所以我把它也删除了。

为你的viewpager添加:

 viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {

            @Override
            public void onPageSelected(int position) {
                array.clear();
                switch (position) {
                    case 1:
                        //like a example
                        setViewPagerByIndex(0);
                        break;
                }
            }

            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
            }

            @Override
            public void onPageScrollStateChanged(int state) {
            }
        });

//on处理程序，以防止crash outofmemory

private void setViewPagerByIndex(final int index){
    Application.getInstance().getHandler().post(new Runnable() {
        @Override
        public void run() {
            viewPager.setCurrentItem(index);
        }
    });
}

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。

如果你知道你想要选择的标签的索引，你可以这样做:

TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
TabLayout.Tab tab = tabLayout.getTabAt(someIndex);
tab.select();

即使你使用TabLayout本身而没有ViewPager(这是非典型的，可能是不好的做法，但我见过这样做)，这种技术也是有效的。