抽屉导航与标签
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......抽屉导航与标签
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。
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
我做了你所说的,但错误仍然一样。 – Arnes 2015-02-24 07:48:22
后logcat错误的崩溃 – 2015-02-24 08:03:24
我在代码错误:“类型不匹配:无法从CategoriesActivity转换为片段”...甚至无法启动应用程序。 但是我几分钟前就已经解决了这个问题。不管怎样,谢谢你。问题在于我在HomeActivity的CategoriesActivity和android.app.Fragment中使用了android.support.v4.app.Fragment,并且调用了碎片的方法。 :) – Arnes 2015-02-24 08:20:56
过得好崩溃,NPE的,当你运行它到底发生了什么? – 2015-02-23 21:38:07
你的班级被称为“CategoriesActivity”,不应该是“CategoryFragment”?除非你没有向我们展示你的CategoryFragment类。 – ekchang 2015-02-23 21:39:05
甚至不能启动应用程序。错误是: case R.id.linearLayoutHome: fragment = new CategoryFragment(); //错误在这里显示 break; – Arnes 2015-02-24 07:42:40