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);
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
只需设置viewpage . setcurrentitem (index)和相关的TabLayout将选择各自的选项卡。
其他回答
这也有帮助
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int i, float v, int i1) {
}
@Override
public void onPageSelected(int i) {
tablayout.getTabAt(i).select();
}
@Override
public void onPageScrollStateChanged(int i) {
}
});
这可能不是最终的解决方案,它需要你使用TabLayout和一个ViewPager,但这是我解决它的方法:
void selectPage(int pageIndex)
{
viewPager.setCurrentItem(pageIndex);
tabLayout.setupWithViewPager(viewPager);
}
我测试了使用这段代码对性能的影响有多大,首先在Android Studio中运行该方法时查看CPU和内存监视器,然后将其与我自己在页面之间导航时(使用滑动手势)对CPU和内存的负载进行比较,结果发现差异并不大,所以至少这不是一个可怕的解决方案……
希望这能帮助到一些人!
如果你正在使用TabLayout和viewPager,那么这有助于你。你可以在addOnpagelistener中使用ViewPager设置TabLayout。
如果你想直接设置TabLayout的位置(不是点击Tab个人)试试下面的代码TabLayout . gettabat (position_you_want_to_set).select()
/* will be invoked whenever the page changes or is incrementally scrolled*/
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
tabLayout.getTabAt(position).select();
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
有点晚了,但可能是一个有用的解决方案。 我直接在我的片段中使用我的TabLayout,并试图在片段的生命周期中选择一个选项卡。 对我来说有用的是等待TabLayout使用android.view绘制完它的子视图。视图# post方法。即:
int myPosition = 0;
myFilterTabLayout.post(() -> { filterTabLayout.getTabAt(myPosition).select(); });
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。