我应该如何选择一个标签在TabLayout编程?

 TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
 tabLayout.setupWithViewPager(viewPager);

当前回答

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);
}

其他回答

试试这个方法。

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

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。

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);
        }
    });
}

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。

试试这个

    new Handler().postDelayed(
            new Runnable(){
                @Override
                public void run() {
                    if (i == 1){
                        tabLayout.getTabAt(0).select();
                    } else if (i == 2){
                        tabLayout.getTabAt(1).select();
                    }
                }
            }, 100);