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Fragment List view replace

When i replace fragment Listview place fragment Listview
I had trouble this in photo but i can't fix it .
i need to fix it,plz.
UI_screenshot
Code
#Override
public void onActivityCreated(Bundle savedInstanceState) {
final String[] titel = {"asdasd", "asda", "bdfg", "asdqweqwe"};
int idimg = R.mipmap.icon_main_list;
MyArrayAdapter adapter = new MyArrayAdapter(getActivity(), titel, idimg);
setListAdapter(adapter);
super.onActivityCreated(savedInstanceState);
}
#Override
public void onListItemClick(ListView l, View v, int position, long id) {
switch (position) {
case 0:
Anmalz anmalz=new Anmalz();
Main_List_Fragment main_list_fragment=new Main_List_Fragment();
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.fragment, anmalz);
fragmentTransaction.remove(main_list_fragment).commit();
break;

Change your onCreateView() to -
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.main_fragment_list, container, false);
}
Also, in onListItemClick(), you should not remove/replace the same fragment again and again. You should just refresh the list adapter.

Fragment is recreate on back press from other Fragment

I am facing a problem in regarding fragment.
In my scenario,
There are two fragment associated with FragmentActivity.
In FragmentActivity, there are a container layout (Frame Layout) in which all fragment will replace.
public void replaceFragment(Fragment fragmentClass) {
String selectedFragment = fragmentClass.getClass().getName();
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager
.beginTransaction();
fragmentTransaction
.replace(R.id.content_frame, fragmentClass);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
First time , I set a List type fragment (Fragment A) in which get the data from web service and papulate over listview. I execute the AsyncTask from onCreateView() method.
In MainActivity: onCreate
SherlockFragment fragment = new FragmentA();
replaceFragment(fragment);
On list item click of Fragment A, Fragment A will callback the activity method to replace it to details type fragment Fragment B.
#Override
public void onAttach(Activity activity) {
// TODO Auto-generated method stub
super.onAttach(activity);
callback = (ICallBack) activity;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
/*View rootView = inflater.inflate(R.layout.fragment_locate, container,
false);*/
View rootView = inflater.inflate(R.layout.fragment_a, container,
false);
ListView list = (ListView) rootView
.findViewById(R.id.listView);
adapter = new MyListAdapter();
list.setAdapter(adapter);
list
.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent,
View convertView, int position, long id) {
SherlockFragment fragment = new SalonDetailFragment();
callback.replaceFragment(fragment);
}
});
ListDataTask task = new ListDataTask();
task.execute();
return rootView;
}
class ListDataTask extends AsynTask<Void,Void,List<Data>>{
public Void doInBackground(Void parems){
List<Data> = getDataFromServer();
}
onPostExecute(List<Data> data){
adapter.addAllData(data);
adapter.notifyDataSetChanged();
}
}
When I press back button, from Fragment B then Application will show Fragment A but it execute Asynctask again and get the data to papulate the listview.
So I need to know, How to maintain the pervious state of Fragment like Activity.
Is there are any way to not to create Fragment after come back from Other activity
Have a look my pseudo code.

I got solution. Simple.... do the check null value of rootview
public class FragmentA extends Fragment {
View _rootView;
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (_rootView == null) {
// Inflate the layout for this fragment
_rootView = inflater.inflate(R.layout.fragment_a, container, false);
// Find and setup subviews
_listView = (ListView)_rootView.findViewById(R.id.listView);
...
} else {
// Do not inflate the layout again.
// The returned View of onCreateView will be added into the fragment.
// However it is not allowed to be added twice even if the parent is same.
// So we must remove _rootView from the existing parent view group
// (it will be added back).
((ViewGroup)_rootView.getParent()).removeView(_rootView);
}
return _rootView

I have the same problem and solved by replacing
fragmentTransaction
.replace(R.id.content_frame, fragmentClass);
to
fragmentTransaction
.add(R.id.content_frame, fragmentClass);
Replace will always create new instance on back press while Add is just add a new fragment in Stack. for more information check this link

Maintain fragment's view state

I have seen Link1 for this issue but could understand it right. I have a fragment that loads a list. When i click the list item it opens another activity. But i press back button it loads the list again. I want it to be at the same scroll position where it was before. In above mentioned link it specifies to use flag but i haven't got the point.
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_dashboard);
android.app.Fragment fragment = new MeFragment();
getFragmentManager().beginTransaction().replace(R.id.layout_FragmentsContainer, fragment).addToBackStack(null).commit();
}
}
public class MeFragment extends Fragment
{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
return inflater.inflate(R.layout.fragment_me, container, false);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
meLV = (ListView) getView().findViewById(R.id.lv_Inbox);
loadingListProgress = (ProgressBar) getView().findViewById(R.id.progress_LoadingList);
meList = new ArrayList<Message>();
meAdapter = new MessagesListAdapter(getActivity(), meList);
//addFooter();
meLV.setAdapter(meAdapter);
meLV.setOnItemClickListener(this);
pageCount = 0;
loadmoreProgressDialog = new ProgressDialog(getActivity());
loadmoreProgressDialog.setTitle("Please wait ...");
loadmoreProgressDialog.setMessage("Loading more ...");
loadmoreProgressDialog.setCancelable(true);
loadUserMessages();
meLV.setOnScrollListener(new EndlessScrollListener() {
#Override
public void onLoadMore(int page, int totalItemsCount) {
// TODO Auto-generated method stub
//addFooter();
loadmoreProgressDialog.show();
loadUserMessages();
}
});
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// TODO Auto-generated method stub
Utils.showToast_msg(getActivity(), "MessageItemClicked");
ReferralDetailFragment fragment = new ReferralDetailFragment();
getFragmentManager().beginTransaction().replace(R.id.layout_FragmentsContainer, fragment).addToBackStack(null).commit();
}
}
public class ReferralDetailFragment extends Fragment implements OnClickListener {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_referraldetail,container, false);
linkToAcknowledge = (TextView) view.findViewById(R.id.lbl_Link_to_Acknowledge);
return view;
}
}

I implemented a simple solution for this in my app, basically when you press back to go to the fragment again, onCreateView() is called. Here in onCreateView() you have done all initialization, so we change
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_me, container, false);
/*
*Whatever you want to do
*
*/
return view;
}
to:
View view;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
if(view==null){
view = inflater.inflate(R.layout.fragment_me, container, false);
/*
*Whatever you want to do
*
*/
}
else{
((ViewGroup)view.getParent()).removeView(view);
}
return view;
}
Here, we move View view outside and make it a class variable. So if it is the first time the fragment is called, it is null and the initialization occurs, otherwise it goes to else black. Else block is required because onCreateView() adds whatever it returns as a child of the view's parent, so since view is already there, we remove it and onCreateView automatically adds it again.

According to our exchange in the comments, I completely deletde my answer and re-write a new one.
I copy/paste the code from one of my apps and removing the useless things and changing the names. Hope there is not too many typing mistakes, at that it is the minimum required to have it working.
When I pop back to FirstFragment from SecondFragment, the scroll position of FirstFragment is the same as when I clicked an item to load the SecondFragment.
Note that I don't extend FragmentActivity. I have an activity which loads the fragments.
Extend/modify to match your needs.
MainActivity :
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_layout);
}
}
FirstFragment Class :
public class FirstFragment extends Fragment implements OnItemClickListener {
private ListView mListView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.first_fragment_layout, container, false);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
mListView = (ListView) getView().findViewById(R.id.listview_first_fragment);
mListView.setAdapter(mAdapter); // depends on your adapter
mListView.setOnItemClickListener(this);
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
mListView.setItemChecked(position, true);
//in case you need, set the bundle here, for example pass the position
Bundle arguments = new Bundle();
arguments.putInt("position", position);
SecondFragment secondFragment = new SecondFragment();
secondFragment.setArguments(arguments);
getFragmentManager().beginTransaction().replace(R.id.fragment_container, secondFragment).addToBackStack(null).commit();
}
}
SecondFragment Class :
public class SecondFragment extends Fragment {
private Integer mPosition;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.second_fragment_layout, container, false);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
Bundle arguments = getArguments();
if (arguments == null) {
mPosition= 0;
} else {
mPosition= arguments.getInt("Position");
}
}
}

What you are trying to achieve may be done with help of savedInstanceState. i also had this kind of problem which i resolved by using add() method instead of replace() in transition.
If you can change your method or already not using add() than give it a shot.
and if add() method didn't do the trick then check the implementation of savedInstanceState.
correctly save instance state.
How to save states of fragment views.

Listview fragment is getting recreated on pressing backbutton

I'm using loader in my ListView fragment, and it's getting recreated on pressing "back" button. Can you tell me how to handle this senario?
Here is my ListView fragment code. Here I have a boolean variable that I'm setting as true on clicking on list item. but once the back button is pressed onCreateView will get called so the backbutton will be false.
public class GTFragment extends SherlockFragment implements LoaderCallbacks<Cursor>{
ListView mTListview = null;
GoogleTasksAdapter mGTasksAdapter = null;
private SQLiteCursorLoader mTLoader=null;
private LoaderManager mTLoaderManager;
private String mSelectedListID = null;
private boolean mIsBackbuttonisPressed = false;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.task_home_activity, container, false);
if(!mIsBackbuttonisPressed)
getLoaderManager().initLoader(0, null, this);
mTListview = (ListView) view.findViewById(R.id.id_task_list_home_activity);
mGTasksAdapter = new GoogleTasksAdapter(getActivity());
mTListview.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> listview,
View clickedview, int position, long arg3) {
// TODO Auto-generated method stub
GoogleTaskItem item = new GoogleTaskItem();
Cursor coursor = ((GoogleTasksAdapter)listview.getAdapter()).getCursor();
if(coursor.moveToPosition(position))
{
mIsBackbuttonisPressed = true;
GoogleTaskController.get_googletask_controllerObj()
.LaunchTaskPreviewActivity();
}
}
});
mTListview.setAdapter(mGTasksAdapter);
mIsBackbuttonisPressed = false;
return view;
}
My fragment activity class code
public class TLActivity extends SherlockFragmentActivity {
LeftSliderTaskListOptions mTaskOptionsFragment = null;
GoogleTasksFragment mTFragment = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
setContentView(R.layout.layout_gt_list);
// FragmentTransaction tfragment = this.getSupportFragmentManager().beginTransaction();
mTFragment = new GTasksFragment();
t.replace(R.id.id_tfragment, mTFragment);
t.commit();
}

instead of
t.replace(R.id.id_tfragment, mTFragment);
use
t.add(R.id.id_tfragment, mTFragment);
It worked for me

I don't think that the accepted answer is right because Fragment.onSaveInstanceState will not be called until the activity hosting it needs to save its state: The docs states:
There are many situations where a fragment may be mostly torn down
(such as when placed on the back stack with no UI showing), but its
state will not be saved until its owning activity actually needs to
save its state.
In other words: if you're using a Activity with multiple fragments for each screen (which is very common), the fragment state will not be saved when you move the next screen.
You also can't use Fragment.setRetainInstance because he's meant only to fragments that aren't on the back stack.
Most of the time, you don't have to think about this but sometimes it's important. Like when you have scrolled a list and want to "remember" the scroll location.
I took a long time to realize that the fragments put on the back stack are kind of saved and you can reuse the view that you already created instead of creating one every time the fragment calls onCreateView. My setup is something like this:
public abstract class BaseFragment extends Fragment {
private boolean mSaveView = false;
private SoftReference<View> mViewReference;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
if (mSaveView) {
if (mViewReference != null) {
final View savedView = mViewReference.get();
if (savedView != null) {
if (savedView.getParent() != null) {
((ViewGroup) savedView.getParent()).removeView(savedView);
return savedView;
}
}
}
}
final View view = inflater.inflate(getFragmentResource(), container, false);
mViewReference = new SoftReference<View>(view);
return view;
}
protected void setSaveView(boolean value) {
mSaveView = value;
}
}
public class MyFragment extends BaseFragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
setSaveView(true);
final View view = super.onCreateView(inflater, container, savedInstanceState);
ListView placesList = (ListView) view.findViewById(R.id.places_list);
if (placesList.getAdapter() == null) { // this check is important so you don't restart your adapter
placesList.setAdapter(createAdapter());
}
}
}

You have multiple options to rectify this issue.
Override onSaveInstanceState like this:
#Override
public void onSaveInstanceState (Bundle outState) {
super.onSaveInstanceState(outState);
outState.putBoolean("mIsBackbuttonisPressed", mIsBackbuttonisPressed);
}
and then in your onCreateView you can get your variable back by:
if (savedInstanceState != null)
mIsBackbuttonisPressed = savedInstanceState.getBoolean("mIsBackbuttonisPressed", false);
You can set this.setRetainInstance(true); in your onCreate method of your fragment.
If you could post your Activity code with creates your fragment I can also tell you other options. (P.S I cannot write it as a comment so posting it in the answer.)

Calling a fragment from another fragment on click

What I want to do is to call one fragment from another on click on item of listview. Program builds without errors however it crash on click on item. Btw I’m making here local Fragment_3 object, I have got already done it in my mainactivity, how to pass it to this function?
Fragment_1.java content:
public class Fragment_1 extends SherlockFragment implements OnItemClickListener{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// requestWindowFeature(Window.FEATURE_NO_TITLE);
View view = inflater.inflate(R.layout.fragment_1, container, false);
ListView listView = (ListView) view.findViewById(R.id.listView1);
listView.setOnItemClickListener(this);
return view;
}
#Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
// TODO Auto-generated method stub
Fragment Fragment3 = new Fragment_3();
Integer fragmentId = (Integer) v.getTag();
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(fragmentId, Fragment3);
fragmentTransaction.commit();
}
}

My suspicion is that v.getTag() is null; So Integer fragmentId = (Integer) v.getTag(); will end up in fragmentId being null. When unboxing that to an int you'll get a NullPointerException. Why don't you replace fragmentId in fragmentTransaction.replace(fragmentId, Fragment3); with the id of the container that holds current instance of Fragment_1?