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
默认情况下,如果你选择一个选项卡,它将高亮显示。如果你想选择显式意味着使用给定的注释代码在onTabSelected(TabLayout。标签标签)与您指定的标签索引位置。这段代码将解释使用viewpager在选项卡选择位置上更改片段。
public class GalleryFragment extends Fragment implements TabLayout.OnTabSelectedListener
{
private ViewPager viewPager;public ViewPagerAdapter adapter;private TabLayout tabLayout;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_gallery, container, false);
viewPager = (ViewPager) rootView.findViewById(R.id.viewpager);
adapter = new ViewPagerAdapter(getChildFragmentManager());
adapter.addFragment(new PaymentCardFragment(), "PAYMENT CARDS");
adapter.addFragment(new LoyaltyCardFragment(), "LOYALTY CARDS");
viewPager.setAdapter(adapter);
tabLayout = (TabLayout) rootView.findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
tabLayout.setOnTabSelectedListener(this);
}
@Override
public void onTabSelected(TabLayout.Tab tab) {
//This will be called 2nd when you select a tab or swipe using viewpager
final int position = tab.getPosition();
Log.i("card", "Tablayout pos: " + position);
//TabLayout.Tab tabdata=tabLayout.getTabAt(position);
//tabdata.select();
tabLayout.post(new Runnable() {
@Override
public void run() {
if (position == 0) {
PaymentCardFragment paymentCardFragment = getPaymentCardFragment();
if (paymentCardFragment != null) {
VerticalViewpager vp = paymentCardFragment.mypager;
if(vp!=null)
{
//vp.setCurrentItem(position,true);
vp.setCurrentItem(vp.getAdapter().getCount()-1,true);
}
}
}
if (position == 1) {
LoyaltyCardFragment loyaltyCardFragment = getLoyaltyCardFragment();
if (loyaltyCardFragment != null) {
VerticalViewpager vp = loyaltyCardFragment.mypager;
if(vp!=null)
{
vp.setCurrentItem(position);
}
}
}
}
});
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
//This will be called 1st when you select a tab or swipe using viewpager
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
//This will be called only when you select the already selected tab(Ex: selecting 3rd tab again and again)
}
private PaymentCardFragment getLoyaltyCardFragment() {
Fragment f = adapter.mFragmentList.get(viewPager.getCurrentItem());
if(f instanceof PaymentCardFragment)
{
return (PaymentCardFragment) f;
}
return null;
}
private LoyaltyCardFragment getPaymentCardFragment() {
Fragment f = adapter.mFragmentList.get(viewPager.getCurrentItem());
if(f instanceof LoyaltyCardFragment)
{
return (LoyaltyCardFragment) f;
}
return null;
}
class ViewPagerAdapter extends FragmentPagerAdapter {
public List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
}
}
其他回答
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) {
}
});
这将不工作的应用程序,有ViewPager2实现,为此,你需要使用
viewPager2.setCurrentItem(position);
当我们使用TabLayoutMediator时,在onConfigureTab中找到onConfigureTab
i.e
TabLayoutMediator tabLayoutMediator = new TabLayoutMediator(
tabLayout, viewPager2, new TabLayoutMediator.TabConfigurationStrategy() {
@Override
public void onConfigureTab(@NonNull TabLayout.Tab tab, int position) {
switch (position){
case 0 : tab.setIcon(getResources().getDrawable(R.drawable.camera));
break;
case 1 : tab.setText("CHAT");
viewPager2.setCurrentItem(position); // when app starts this will be the selected tab
break;
case 2 : tab.setText("STATUS");
break;
case 3 : tab.setText("CALL");
break;
}
}
}
);
tabLayoutMediator.attach();
如果您在理解上有困难,这段代码可以帮助您
private void MyTabLayout(){
TabLayout.Tab myTab = myTabLayout.newTab(); // create a new tab
myTabLayout.addTab(myTab); // add my new tab to myTabLayout
myTab.setText("new tab");
myTab.select(); // select the new tab
}
你也可以在你的代码中添加这个:
myTabLayout.setTabTextColors(getColor(R.color.colorNormalTab),getColor(R.color.colorSelectedTab));
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。
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);