问题描述
这是我目前面临的问题。我已经从Eclipse与ADT插件切换到Android Studio最近,我从来没有遇到的Eclipse出现在Android studio。
Here is the problem i am currently facing. I have switched from Eclipse with ADT plugin to Android Studio recently and an error i never encountered on Eclipse appeared with Android studio.
当我切换到一个特定的片段LineFragment 我收到以下错误:
When I switch to a specific fragment called "LineFragment" I get the following error :
java.lang.NullPointerException: Attempt to write to field 'int android.support.v4.app.Fragment.mNextAnim' on a null object reference
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:708)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1489)
at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:486)
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1073)
at android.support.v4.view.ViewPager.populate(ViewPager.java:919)
at android.support.v4.view.ViewPager$3.run(ViewPager.java:249)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
at android.view.Choreographer.doCallbacks(Choreographer.java:580)
at android.view.Choreographer.doFrame(Choreographer.java:549)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
它似乎与片段为null等等有关。我在互联网上搜索,但只有很少的人遇到这样的东西。
It seems to have something to do with the fragment being null or so. I have search on the internet but only very few people have encoutered something like that.
这是我的片段的代码(它扩展了android.support.v4.app。片段像所有3个片段)
Here is the code of my fragment (it extends android.support.v4.app.Fragment like all the 3 fragments)
public class LineFragment extends Fragment{
private View v;
private ListView list;
private LineList listAdapter;
private Home home; // Current activity
public static LineFragment newInstance(String chaine) {
LineFragment fragment = new LineFragment ();
Bundle args = new Bundle();
args.putString("LIGNE", chaine);
fragment.setArguments(args);
return fragment;
}
@Override
public void onActivityCreated(Bundle savedState) {
super.onActivityCreated(savedState);
registerForContextMenu(list);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
v = inflater.inflate(R.layout.fragment_ligne, container, false);
home = (Home) this.getActivity();
initInterface();
attachReactions();
setHasOptionsMenu(true);
return v;
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.line_menu, menu);
MenuItem searchMenuItem = menu.findItem(R.id.action_search);
SearchManager searchManager = (SearchManager) getActivity().getSystemService( Context.SEARCH_SERVICE );
SearchView search = (SearchView) MenuItemCompat.getActionView(searchMenuItem);
SearchViewCompat.setInputType(search, InputType.TYPE_CLASS_TEXT|InputType.TYPE_TEXT_VARIATION_POSTAL_ADDRESS);
search.setSearchableInfo(searchManager.getSearchableInfo(home.getComponentName()));
//search.setSubmitButtonEnabled(true);
int id = search.getContext().getResources().getIdentifier("android:id/search_src_text", null, null);
TextView textView = (TextView) search.findViewById(id);
textView.setTextColor(Color.WHITE);
textView.setHintTextColor(Color.WHITE);
search.setOnQueryTextListener(new GreenOnQueryTextListener(list));
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public void onResume() {
super.onResume();
Log.d("OnResume()", "Ligne");
}
@Override
public void setUserVisibleHint(boolean visible){
super.setUserVisibleHint(visible);
if (visible && isResumed()){
//Only manually call onResume if fragment is already visible
//Otherwise allow natural fragment lifecycle to call onResume
onResume();
}
}
/**
* Initializes the graphical interface of the fragment.
*/
private void initInterface(){
list = (ListView) v.findViewById(R.id.list);
list.setTextFilterEnabled(true);
}
/**
* Sets the reactions of the control elements
*/
private void attachReactions(){
ArrayList<Ligne> lignes = new ArrayList<Ligne>(Globale.engine.getReseau().getLignes().values());
listAdapter = new LineList(getActivity(), lignes);
list.setAdapter(listAdapter);
list.setOnItemClickListener(new LineClickListener(home));
}
这是我的PagerAdapter:
Here is my PagerAdapter :
public class KiceoFragmentPagerAdapter extends FragmentPagerAdapter{
private final int PAGE_COUNT = 3;
public KiceoFragmentPagerAdapter(FragmentManager fm) {
super(fm);
// TODO Auto-generated constructor stub
}
@Override
public int getCount() {
return PAGE_COUNT;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
// Top Rated fragment activity
return new LineFragment();
case 1:
// Games fragment activity
return new StopFragment();
case 2:
// Movies fragment activity
return new CustomMapFragment();
}
return new LineFragment();
}
}
有谁有一个线索来自哪里?这是否真的与Android Studio有关系? Thanx
Does anyone have a clue where this is coming from ? Does it really have something to do with Android Studio ? Thanx
我尝试切换支持V13片段,但没有改变任何东西。
I tried switching to support V13 fragments but It didn't change anything.
推荐答案
只需检查 getItem()
是否为分段返回
。如果这样设置了默认的 null
Fragment
!
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