TabLayout的标签没有显示

Question

我有一个主要活动,它承载一个片段,该片段反过来托管一个TabLayout(带有一个ViewPager).显示标签栏,但标签本身未显示.

这是我在显示主机片段的主要活动中的代码:

        Fragment fragment = new BMITabsFragment();

        FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).addToBackStack(Constants.BMI_TABS_FRAGMENT).commit();

这是我托管TabLayout的片段,它是BMITabsFragment(sa):

public class BMITabsFragment extends Fragment {
...
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {
        mParam1 = getArguments().getString(ARG_PARAM1);
        mParam2 = getArguments().getString(ARG_PARAM2);
    }

}

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

    // Get the ViewPager and set it's PagerAdapter so that it can display items
    ViewPager viewPager = (ViewPager) view.findViewById(R.id.viewpager);
    viewPager.setAdapter(new BMIFragmentPagerAdapter(getActivity().getSupportFragmentManager(),
            getActivity()));

    // Give the TabLayout the ViewPager
    TabLayout tabLayout = (TabLayout) view.findViewById(R.id.sliding_tabs);
    tabLayout.setupWithViewPager(viewPager);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View view = inflater.inflate(R.layout.fragment_bmitabs, container, false);
    return view;
}
...
}

这是我的FragmentPagerAdapter:

public class BMIFragmentPagerAdapter extends FragmentPagerAdapter {

final int PAGE_COUNT = 2;
private FragmentManager fragmentManager;
private Context context;

public BMIFragmentPagerAdapter(FragmentManager fm, Context context) {
    super(fm);
    this.context = context;
    this.fragmentManager = fm;

}

public BMIFragmentPagerAdapter(FragmentManager fm) {
    super(fm);
    fragmentManager = fm;

}

@Override
public CharSequence getPageTitle(int position) {
    String[] pageTitles = context.getResources().getStringArray(R.array.page_titles_array);
    return pageTitles[position];
}

@Override
public Fragment getItem(int position) {
    SharedPreferences prefs = context.getSharedPreferences(Constants.SHARED_PREFS_FILE, 0);
    long patientId = prefs.getLong(Constants.SELECTED_PATIENT_ID, 1);
    Fragment fragment = null;
    switch (position){
        case 0:
            return BMITabelleFragment.newInstance(patientId);

        case 1:
            return BMIChartFragment.newInstance(patientId);

        default:
            return BMITabelleFragment.newInstance(patientId);
    }
}

@Override
public int getCount() {
    return PAGE_COUNT;
}
}

这是fragment_bmitabs.xml:

<?xml version="1.0" encoding="utf-8"?>

<android.support.design.widget.TabLayout
    android:id="@+id/sliding_tabs"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:tabMode="scrollable" />

<android.support.v4.view.ViewPager
    android:id="@+id/viewpager"
    android:layout_width="match_parent"
    android:layout_height="0px"
    android:layout_weight="1"
    android:background="@android:color/white" />

</LinearLayout>

我的代码基于Google Android指南,网址为https://github.com/codepath/android_guides/wiki/Google-Play-Style-Tabs-using-TabLayout

我在这里缺少什么？

注意:我正在使用AppCompatActivity和支持库v4和v7以及com:android:support:design库

Answer 1

我也有同样的问题!但这也解决了我.

tabLayout.post(new Runnable() {
    @Override
    public void run() {
        tabLayout.setupWithViewPager(viewPager);
    }
});

https://code.google.com/p/android/issues/detail?id=180462

Answer 2

之后设置标签图标 setupWithViewPager()

private void setTabs {
   tabLayout.setupWithViewPager(viewPager);
   setupTabIcons();
} 

private void setupTabIcons() {
   tabLayout.getTabAt(0).setIcon(tabIcons[0]);
   tabLayout.getTabAt(1).setIcon(tabIcons[1]);
   tabLayout.getTabAt(2).setIcon(tabIcons[2]);
}

Answer 3

就像@Nathaniel Ford说的,这应该是一个bug,我改为使用设计库23.0.1.google修复它,所以build.gradle改为compile 'com.android.support:design:23.0.1'.ps:你也必须改变你compileSdkVersion的23岁