我有两个片段应该像图片中那样工作。
使用平板电脑 AVD 它可以完美运行,但是当我使用手机 AVD 时,总是会出现以下错误消息:
10-15 07:31:46.450: E/AndroidRuntime(721): FATAL EXCEPTION: main
10-15 07:31:46.450: E/AndroidRuntime(721): java.lang.IllegalStateException: Fragment EventsFragment{411e6440 id=0x7f070005} not attached to Activity
10-15 07:31:46.450: E/AndroidRuntime(721): at android.support.v4.app.Fragment.getLoaderManager(F ragment.java:823)
10-15 07:31:46.450: E/AndroidRuntime(721): at com.example.activity.EventsFragment.updateEventsVi ew(EventsFragment.java:80)
10-15 07:31:46.450: E/AndroidRuntime(721): at com.example.activity.EventsActivity.onYearSelected (EventsActivity.java:79)
10-15 07:31:46.450: E/AndroidRuntime(721): at com.example.activity.YearsFragment.onListItemClick (YearsFragment.java:63)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.support.v4.app.ListFragment$2.onItemClick( ListFragment.java:58)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.widget.AdapterView.performItemClick(Adapte rView.java:298)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.widget.AbsListView.performItemClick(AbsLis tView.java:1086)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.widget.AbsListView$PerformClick.run(AbsLis tView.java:2859)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.widget.AbsListView$1.run(AbsListView.java: 3533)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.os.Handler.handleCallback(Handler.java:615 )
10-15 07:31:46.450: E/AndroidRuntime(721): at android.os.Handler.dispatchMessage(Handler.java:92 )
10-15 07:31:46.450: E/AndroidRuntime(721): at android.os.Looper.loop(Looper.java:137)
10-15 07:31:46.450: E/AndroidRuntime(721): at android.app.ActivityThread.main(ActivityThread.jav a:4745)
10-15 07:31:46.450: E/AndroidRuntime(721): at java.lang.reflect.Method.invokeNative(Native Method)
10-15 07:31:46.450: E/AndroidRuntime(721): at java.lang.reflect.Method.invoke(Method.java:511)
10-15 07:31:46.450: E/AndroidRuntime(721): at com.android.internal.os.ZygoteInit$MethodAndArgsCa ller.run(ZygoteInit.java:786)
10-15 07:31:46.450: E/AndroidRuntime(721): at com.android.internal.os.ZygoteInit.main(ZygoteInit .java:553)
10-15 07:31:46.450: E/AndroidRuntime(721): at dalvik.system.NativeStart.main(Native Method)
使用的 AVD:平板电脑:平台:3.0 API 级别:11 手机:平台:4.1.2 API 级别:16
事件活动.java
public class EventsActivity extends FragmentActivity implements YearsFragment.OnYearSelectedListener{
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.years_events);
if (findViewById(R.id.fragment_container) != null) { //Handset
if (savedInstanceState != null) {
return;
}
//Fragment A
YearsFragment firstFragment = new YearsFragment();
firstFragment.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction().add(R.id.fragment_container, firstFragment).commit();
}
}
@Override
public void onYearSelected(Years year) {
EventsFragment eventFrag = (EventsFragment) getSupportFragmentManager().findFragmentById(R.id.event_fragment);
if (eventFrag != null) { //Tablet
//update Fragment B
eventFrag.updateEventsView(year);
} else { //Handset
//start Fragment B
EventsFragment newFragment = new EventsFragment();
newFragment.updateEventsView(year);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
transaction.commit();
}
}}
事件片段(片段 B)
public class EventsFragment extends ListFragment implements LoaderManager.LoaderCallbacks<List<Events>>{
EventsAdapter adapter;
private int year;
OnEventSelectedListener mCallback;
public interface OnEventSelectedListener {
public void onEventSelected(Events event);
}
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);
adapter = new EventsAdapter(getActivity());
setListAdapter(adapter);
setEmptyText("No Data Here");
setListShown(false);
year = Calendar.getInstance().get(Calendar.YEAR);
getLoaderManager().initLoader(year, null, this);
}
@Override
public void onAttach(Activity activity){
super.onAttach(activity);
try{
mCallback = (OnEventSelectedListener) activity;
} catch (ClassCastException e){
throw new ClassCastException(activity.toString() + "must implement OnEventsSelectedListener");
}
}
@Override
public void onListItemClick(ListView l, View v, int position, long id) {
mCallback.onEventSelected(adapter.getItem(position));
}
public void updateEventsView(Years year) {
this.year = Integer.parseInt(year.getYear());
getLoaderManager().initLoader(this.year, null, this); //TODO error }
//Loader
@Override
public Loader<List<Events>> onCreateLoader(int arg0, Bundle arg1) {
return new EventsLoader(getActivity(),this.year);
}
@Override
public void onLoadFinished(Loader<List<Events>> arg0, List<Events> data) {
adapter.setData(data);
if(isResumed()){
setListShown(true);
}else{
setListShownNoAnimation(false);
}
}
@Override
public void onLoaderReset(Loader<List<Events>> arg0) {
adapter.setData(null);
}
为什么它不适用于手机?
问候Mr.P。