抽屉导航与标签

Question

谷歌搜索三天。不能帮助自己。我有导航抽屉和片段，除了片段中的标签外，一切都很完美。这是MainActiviti类的一部分......

case R.id.linearLayoutHome: 
     fragment = new HomeFragment(); 
     break; //this one works well 

case R.id.linearLayoutHome: 
     fragment = new CategoryFragment(); //error showing here 
     break; //this one doesn't work 

调用片段...

FragmentManager fragmentManager = getFragmentManager(); 
     fragmentManager.beginTransaction().replace(R.id.container, fragment).commit(); 

首页片段，它可以完美运行：

public class HomeFragment extends Fragment { 
public HomeFragment() { 
} 

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
    View rootView = inflater.inflate(R.layout.fragment_home, container, false); 
    return rootView; 
    } 

} 

CategoryFragment不工作。我认为这是因为片段中的片段：

public class CategoriesActivity extends Fragment { 

SectionsPagerAdapter mSectionsPagerAdapter; 
ViewPager mViewPager; 

public CategoriesActivity(){ 
} 

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
    View rootView = inflater.inflate(R.layout.fragment_home, container, false); 

    mSectionsPagerAdapter = new SectionsPagerAdapter(getChildFragmentManager()); 

    mViewPager = (ViewPager) rootView.findViewById(R.id.pager); 
    mViewPager.setAdapter(mSectionsPagerAdapter); 

    return rootView; 
} 

public class SectionsPagerAdapter extends FragmentPagerAdapter { 

    public SectionsPagerAdapter(FragmentManager fm) { 
     super(fm); 
    } 

    @Override 
    public Fragment getItem(int position) { 
     Fragment fragment = new DummySectionFragment(); 
     Bundle args = new Bundle(); 
     args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1); 
     fragment.setArguments(args); 
     return fragment; 
    } 

    @Override 
    public int getCount() { 
     return 2; 
    } 

    @Override 
    public CharSequence getPageTitle(int position) { 
     Locale l = Locale.getDefault(); 
     switch (position) { 
     case 0: 
      return getString(R.string.title1).toUpperCase(l); 
     case 1: 
      return getString(R.string.title2).toUpperCase(l); 
     } 
     return null; 
    } 
} 

public static class DummySectionFragment extends Fragment { 

    public static final String ARG_SECTION_NUMBER = "section_number"; 

    public DummySectionFragment() { 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
     View rootView = inflater.inflate(R.layout.fragment_tabbed_dummy, container, false); 
     TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label); 
     dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER))); 
     return rootView; 
    } 
} 

} 

我需要一些解决方案。没有更多的想法。

Answer 1

STEP 1： 你onCreateView()应该是这样的：

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
    View rootView = inflater.inflate(R.layout.fragment_home, container, false); 
    return rootView; 
} 

而且这种方法添加到您的Fragment：

@Override 
public void onViewCreated(View view, Bundle savedInstanceState){ 
    mSectionsPagerAdapter = new SectionsPagerAdapter(getChildFragmentManager()); 
    mViewPager = (ViewPager) view.findViewById(R.id.pager); 
    mViewPager.setAdapter(mSectionsPagerAdapter); 
} 

STEP 2： 确保您Activity从FragmentActivity或ActionBarActivity延伸。

第3步： 确保您使用android.support.v4.app.Fragment而不是android.app.Fragment