Question

我有一项活动需要view pager。所以我定义了5个片段，并按照谷歌文档中显示的视图寻呼机。但我无法看到为TabLayout定义的页面标题。

活动代码：

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_kannada);
        viewPager = (ViewPager) findViewById(R.id.viewPager);

        //Adapter to populate ViewPager
        CategoryAdapter adapter = new CategoryAdapter(this,getSupportFragmentManager());
        viewPager.setAdapter(adapter);

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

    }

适配器代码：

public class CategoryAdapter extends FragmentPagerAdapter {

//Number of pages in the ViewPager
private final int NUM_PAGES = 5;
//Context of the app
private Context mContext;

public CategoryAdapter(Context context,FragmentManager fm){
    super(fm);
    mContext = context;
    Toast.makeText(mContext,"Inside Custom Adapter",Toast.LENGTH_SHORT).show();
}
@Override
public Fragment getItem(int position) {
    if (position == 0) {
        return new ChatFragment();
    } else if (position == 1) {
        return new FamilyFragment();
    } else if (position == 2) {
        return new ColorsFragment();
    } else if (position == 3){
        return new PhrasesFragment();
    }
    else {
        return new NumbersFragment();
    }
}

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

@Override
public CharSequence getPageTitle(int position) {
    if (position == 0) {
        return mContext.getString(R.string.category_numbers);
    } else if (position == 1) {
        return mContext.getString(R.string.category_family);
    } else if (position == 2) {
        return mContext.getString(R.string.category_colors);
    } else if(position == 3) {
        return mContext.getString(R.string.category_phrases);
    }
    else{
        return mContext.getString(R.string.category_chat);
    }
}
}

片段：

public class NumbersFragment extends Fragment {

public NumbersFragment(){

}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_layout,container,false);

    String[] languages = {"Kannada","Tamil","Telugu","Malayalam","Bengali"}; //String array with language name
    ListAdapter arrayAdapter = new ArrayAdapter<String>(getActivity(),android.R.layout.simple_list_item_1,languages);
    ListView listView = (ListView)rootView.findViewById(R.id.list);
    listView.setAdapter(arrayAdapter);
    Toast.makeText(getActivity(),"Inside Numbers Fragment",Toast.LENGTH_SHORT).show();

    return rootView;
}
}

activity_kannada：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.arqamahmad.languageslearnandtalk.Kannada">

    <android.support.v4.view.ViewPager
        android:id="@+id/viewPager"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <android.support.design.widget.TabLayout
        android:id="@+id/tabLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="top" />


</LinearLayout>

那么为什么会出现这个问题，因为我无法看到其他任何方法。我只是将片段作为普通页面而没有TabLayout在顶部。

ViewPager没有显示包含片段标题的TabLayout

0 个答案: