我有一个扩展ListFragment的片段，当我最小化应用程序并返回它时，listview为空。
它不会自动恢复吗？
public class LocationListViewFrag extends ListFragment implements AdapterView.OnItemClickListener {
private static final String TAG = "LocationListViewFrag";
private ArrayList<LocationObj> mLocations = new ArrayList<>();
private LocationAdapter mTaxAdapter;
private LocationListViewListener mListener;
@Bind(R.id.listLabel)
TextView listLabel;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mTaxAdapter = new LocationAdapter(getActivity(), mLocations);
setListAdapter(mTaxAdapter);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_tax_location_list, container, false);
ButterKnife.bind(this, v);
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
getListView().setOnItemClickListener(this);
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
try {
mListener = (LocationListViewListener) context;
} catch (ClassCastException e) {
throw new ClassCastException(context.toString() + " must implement LocationListViewListener");
}
}
public void setLocations(ArrayList<LocationObj> Locations) {
mLocations = Locations;
mTaxAdapter.clear();
mTaxAdapter.addAll(mLocations);
mTaxAdapter.notifyDataSetChanged();
if(mLocations.isEmpty()){
listLabel.setVisibility(View.VISIBLE);
} else {
listLabel.setVisibility(View.GONE);
}
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
LocationObj aLocation = mLocations.get(position);
Log.d(TAG, String.format("Clicked - %s", aLocation.toString()));
mListener.onLocationSelected(aLocation);
}
public interface LocationListViewListener {
void onLocationSelected(LocationObj LocationObj);
}
}
活动
onCreate@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.free_tax_prep_providers_new);
initDrawer();
ButterKnife.bind(this);
if (savedInstanceState != null) {
//Restore the fragment's instance
mLocationListViewFrag = (LocationListViewFrag)getSupportFragmentManager().getFragment(savedInstanceState, "mLocationListViewFrag");
} else if (findViewById(R.id.fragment_container) != null) {
// Check that the activity is using the layout version with
// the fragment_container FrameLayout
// Create a new Fragment to be placed in the activity layout
mLocationListViewFrag = new LocationListViewFrag();
// Add the fragment to the 'fragment_container' FrameLayout
getSupportFragmentManager().beginTransaction()
.add(R.id.fragment_container, mLocationListViewFrag).commit();
}
}
onSavedInstance@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
//Save the fragment's instance
getSupportFragmentManager().putFragment(outState, "mLocationListViewFrag", mLocationListViewFrag);
}
最佳答案
实际上，您可以在片段本身而不是活动中覆盖onSaveInstanceState。当我处理列表片段时，这样做对我来说很有效。