I have a widget, which opens a Fragment showing a list of contacts with their pictures. This Fragment consumes a lot of memory. On leaving the Fragment, the memory is still allocated...
public class ListFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle bundle) {
final List<BWContact> contacts = ContactHandler.getByGroup(group);
final ListView listView = (ListView) this.getActivity().findViewById(R.id.contact_list);
listView.setAdapter(new BWContactAdapter(getActivity(), contacts, true));
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> a, View v, int position, long id) {
...
}
});
return null;
}
#Override
public void onDestroyView() {
super.onDestroyView();
}
}
How can I tell the fragment to free the memory?
I don't understand this line:
final ListView listView = (ListView) this.getActivity().findViewById(R.id.contact_list);
Is your list attached to the activity? In this case, yes the activity will retain the listView with all the contacts.
Related
I have just one fragment attached to an activity using replace. When the device locks the screen after a few seconds and then I unlock it, the onItemSelected method assigned to some spinner gets executed, even though the fragment views (EditTexts and so) and the spinner selected item remains the same.
public class MyFragment extends Fragment {
private Spinner mySpinner;
public static MyFragment newInstance() {
return new MyFragment();
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.some_layout, container, false);
mySpinner = (Spinner)view.findViewById(R.id.my_spinner);
List<String> items = new ArrayList<>();
items.add("Anything");
items.add("Anything");
items.add("Anything");
ArrayAdapter<String> adapter =
new ArrayAdapter<String>(
getContext(),
android.R.layout.simple_spinner_item,
items);
mySpinner.setAdapter(adapter);
mySpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(getContext(), "Hello World", Toast.LENGTH_LONG).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
return view;
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
Every time I select an item I get the toast message "Hello World" (or any other method or action assigned to the listener), but when the device locks and then I unlock, I'm still getting the message as if the method onItemSelected was called.
I've been trying to mess around with booleans and Fragment's onSaveInstanceState and onActivityCreated methods, but I haven't figured out a way to stop onItemSelected method from executing when the device returns from a locked screen.
The problem is that onItemSelected is called after Spinner is initialised, solution is to put mySpinner.setSelection(position, false) before mySpinner.setOnItemSelectedListener
refer to this
I have a fragment with a viewpager with adapter extending FragmentStatePagerAdapter with three slidable fragments inside. the main fragment has a static list of data, and three sub-fragments references and show the same list (don't ask why). The list item can be removed by a button inside the row layout or by clicking clear-all button after the list in each of those three fragments.
My problem is that after removing one or all the items with the buttons, sometimes i get an instant index out of bounds exception (no application code in stack trace, to find where the exception is coming from) or randomly sometimes removal work, but fragments nearby display old data with the extra item, and clicking to remove it ofcourse throws out of bounds exception, because after some debugging I can see that size of list passed to adapter to recreate the nearby fragment is lower by one (removal is successful) so I believe the list is not notified/invalidated correctly. Any help, since stacktrace can't help?
Btw I'm using FragmentStatePagerAdapter.POSITION_NONE to recreate the fragments with new data on each swipe, notifyDataSetChanged to notify the adapter of changed data, and invalidate() the listview in onViewCreated(), but they don't help.
relevant code:
Main Fragment
public class MainFragment extends BaseFragment<CategoryTreeItem> {
public static List<Map.Entry<EventTreeItem, String>> betList = new ArrayList<>();
...
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
ViewPager mViewPager = (ViewPager) view.findViewById(R.id.viewpager);
mViewPager.setAdapter(new MyPagerAdapter(getChildFragmentManager()));
SlidingTabLayout mSlidingTabLayout = (SlidingTabLayout) view.findViewById(R.id.sliding_tabs);
mSlidingTabLayout.setViewPager(mViewPager);
}
}
class MyPagerAdapter extends FragmentStatePagerAdapter {
private List<String> items;
public MyPagerAdapter(FragmentManager fm) {
super(fm);
items = getResources().getStringArray(R.array.three_categories);
}
#Override
public Fragment getItem(int i) {
Fragment fragment;
switch (i) {
case 0:
fragment = new FirstFragment();
return fragment;
case 1:
fragment = new SecondFragment();
return fragment;
case 2:
fragment = new ThirdFragment();
return fragment;
default:
return null;
}
}
...
#Override
public int getItemPosition(Object object) {
return FragmentStatePagerAdapter.POSITION_NONE;
}
}
Three fragments (they are needed since the layout and functionality is a bit different)
public class First/Second/ThirdFragment extends BaseListFragment<ArrayList<EventTreeItem>> {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_main, container, false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
MyListAdapter adapter = new MyListdapter(getActivity(), R.layout.item_first/second/thirdfragment, MainFragment.betList);
getListView().setItemsCanFocus(true);
View footerView = getLayoutInflater(savedInstanceState).inflate(R.layout.include_first/second/third_footer, getListView(), false);
getListView().addFooterView(footerView);
adapter.notifyDataSetChanged();
setListAdapter(adapter);
getListView().invalidate();
//handles REMOVE ALL button for all fragments footer button
Helper.setUpClearOption(footerView, adapter);
}
}
MyListAdapter
#CompileStatic
public class MyListAdapter extends ArrayAdapter<Map.Entry<EventTreeItem,String>> {
private int mResourceId;
private List<Map.Entry<EventTreeItem,String>> mObjects;
public MyListAdapter(Context context, int resource, List<Map.Entry<EventTreeItem,String>> objects) {
super(context, resource, objects);
mResourceId = resource;
mObjects = objects;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = convertView;
if (view == null) {
view = LayoutInflater.from(getContext()).inflate(mResourceId, parent, false);
}
//------setting a lot of text for textViews
// .....
//------
ImageView ivRemove = (ImageView) view.findViewById(R.id.ivRemove);
ivRemove.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//Tried removing directly from adapter, not helping
// MyListAdapter.this.remove(mObjects.get(position));
MainFragment.betList.remove(position);
MyListAdapter.this.notifyDataSetChanged();
}
});
return view;
}
}
Remove All helper method (also returning instant OOB or not notifying neighbor fragments)
public static void setUpClearOption(View view, final ArrayAdapter adapter) {
ImageView ivRemoveAll = (ImageView) view.findViewById(R.id.ivRemoveAll);
ivRemoveAll.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
adapter.clear();
adapter.notifyDataSetChanged();
}
});
}
So any help is much appreciated!
I managed to fix My problem by creating three listadapters for each of my fragments (static adapters instantiaiting with null value ) and in onClick I check each of those three adapters if they are not null (since adapters are null until after onViewCreated, and it is called only when the current fragment is a neighbor). All three adapters use the same data.
I have a problem when try to add setOnItemClickListener into a Fragment.
This is my Fragment.
public class LocalesFragmento extends Fragment {
ListView locales_list;
private List localesList;
private Context context;
public LocalesFragmento() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View vista = inflater.inflate(R.layout.locales_list, container, false);
locales_list = (ListView) vista.findViewById(R.id.localesList);
new getLocalesAsyncTask().execute();
return vista;
}
private void setListAdapter() {
Log.e("Adapter","Adapter...");
locales_list.setAdapter(new LocalesAdapter(getActivity(), getActivity(), localesList));
locales_list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
//detailInstagram(list.get(position));
}
});
}
The setOnItemClickListener is never executed. Any ideas?
Do I need to implement some other method?
Thanks.
Best regards.
You start your AsyncTask on onActivityCreated method because here before attaching the layout you are starting an async and that may be the reason why the listener is setting up.
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
locales_list.setAdapter(new LocalesAdapter(getActivity(), getActivity(), localesList));
locales_list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
//detailInstagram(list.get(position));
}
});
new getLocalesAsyncTask().execute();
}
Your LocalesAdapter might be the cause. You are passing the context (getActivity()) to the adapter twice.
locales_list.setAdapter(new LocalesAdapter(getActivity(), getActivity(), localesList));
Make your that the arguments passed to the LocalesAdapter are correct.
I have a main activity which consists of spinner + 3 fragments (tabs). I want to access spinner value from fragment. So I wrote this code into onActivityCreated inside my fragment:
final Spinner spinner = (Spinner) getView().findViewById(R.id.spinnerOblasti);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
/*TextView[] vystrahy = new TextView[1];
vystrahy[0] = (TextView) getView().findViewById(R.id.txtVystrahy);
(new htmlParser(vystrahy, 0) ).execute(new Integer[]{spinner.getSelectedItemPosition()});*/
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
but when I run my application spinner throws nullpointerexception. Any ideas on how to access it from fragment?
Here is my onCreateView which I believe is causing problem but I dont know how to fix it:
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_tab1, container, false);
return rootView;
}
Thanks in forward
Doesn't work like that, what do you mean for spinner value? If you want to access to the spinner object you have to setup an interface which will be implemented by your activity and then in onActivityCreated you can call the method of that interface to do something. For example:
public class MyClass implements MyInterface {
public interface MyInterface {
void doSomethingWithSpinner();
}
public void doSomethingWithSpinner() {
mySpinner.setVisibility(View.VISIBLE);
}
}
And your onActivityCreated:
if(getActivity() instanceof MyInterface) {
((MyInterface)getActivity()).doSomethingWithSpinner();
}
I developed an app which fills a list. It works fine in the way I did it but I'm not conviced that I solved the problem in a recommended way. I read that you should override onActivityCreated in a Fragment and fill the list there instead of doing this in onCreateView. onCreateView should only be used to inflate static views. Is this true? If yes, how should these two methods look like in the end?
This is my Fragment class:
public class FragmentMain extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
List<MyItem> items = createListItems();
ListView listView = (ListView) view.findViewById(R.id.list);
MyListAdapter adapter = new MyListAdapter(view.getContext(), items);
listView.setAdapter(adapter);
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Toast.makeText(view.getContext(),
"Clicked " + position, Toast.LENGTH_LONG)
.show();
}
});
return view;
}
.
.
.
}
My MainActivity just adds the fragment:
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentMain fm = new FragmentMain();
getFragmentManager().beginTransaction()
.add(R.id.fragment_main_container, fm).commit();
}
.
.
.
}
That is true to a certain extend only because onCreateView happens on the UI thread and you don't want anything slowing that down otherwise your UI will be slow and choppy. For example, in your fragment class you have a call to a method "createListItems()". I don't know how many items you're making but if it's a lot it could slow down your UI (especially if youre accessing a database and querying objects and so on). So you could do it in onActivityCreated but you could also use an AsyncTask. So your code would become something like this:
public class LoadListObjectsTask extend AsyncTask<Void, List<MyItem>, Void> {
private MyListAdapter myListAdapter;
private Context mContext;
public LoadListObjectsTask(Context context) {
this.mContext = context;
}
#Override
public void doInBackground(Void...params) {
//create your list objects here instead of on UI thread. This will run on a separate thread.
myListAdapter = new MyListAdapter(mContext, items);
return items; //return list of MyItems
}
//This is called when doInBackground is done. THIS WILL RUN ON THE UI THREAD So don't do
//anything slow here
#Override
public void onPostExecute(List<MyItem>...params //don't really need the list here//) {
listView.setAdapter(myListAdapter);
}
}
then in your fragment
public class FragmentMain extends Fragment {
private ListView listView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
List<MyItem> items = new ArrayList<MyItem>();
listView = (ListView) view.findViewById(R.id.list);
//new code
new LoadListObjectsTask(getActivity()).execute();
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Toast.makeText(view.getContext(),
"Clicked " + position, Toast.LENGTH_LONG)
.show();
}
});
return view;
}
public void onResume()... {
//also add the task here so your content is reloaded on resume..
new LoadListObjectsTask(getActivity()).execute();
}
.
.
.
}
If you don't want to do this just make your List of MyItems a private field and move
List<MyItem> items = createListItems();
to onActivityCreated().
Hope that helps!