MainActivity on startup add a fragment layout to Relativeview, then i send a data to fragment to add it to ExpandablelistView but my app shows me error that couldn't recognize ExpandablelistView.
MainActivity:
public class MainActivity extends AppCompatActivity implements FragmentAddCatergory.onClickButtonListener {
private FragmentManager manager;
private FragmentTransaction transactionShowList;
private FragmentTransaction transactionAddCatergory;
private FragmentAddCatergory addCatergory;
private FragmentShowCategory showCategory;
private boolean addcategory;
private TextView txtAddCategory;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
manager = getFragmentManager();
transactionShowList = manager.beginTransaction();
showCategory = new FragmentShowCategory();
addCatergory=new FragmentAddCatergory();
transactionShowList.add(R.id.Fragment_container, showCategory);
transactionShowList.commit();
addcategory=false;
txtAddCategory = (TextView) findViewById(R.id.txtaddcategory);
txtAddCategory.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
ChangeFragment();
}
});
}
public void ChangeFragment(){
transactionAddCatergory=manager.beginTransaction();
if (addcategory){
transactionAddCatergory.replace(R.id.Fragment_container,addCatergory);
txtAddCategory.setText("Do you want to see your List?Show me!");
addcategory=false;
}else{
transactionAddCatergory.replace(R.id.Fragment_container,showCategory);
txtAddCategory.setText("Do you want to add a Category?Create One");
addcategory=true;
}
transactionAddCatergory.commit();
}
#Override
public void ClickButton(String group, String child) {
FragmentShowCategory a=new FragmentShowCategory();
a.showExpand(this,group,child);
}}
in last above code i make object from first fragment and send a data and in below code is code of first fragment
public class FragmentShowCategory extends Fragment {
private View view;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
view = inflater.inflate(R.layout.activity_expandable_list_view, container, false);
return view;
}
public void showExpand(Context context, String g, String c) {
Toast.makeText(context, g + " is " + c, Toast.LENGTH_LONG).show();
HashMap<String, List<String>> carsDetails = DataProvider.getInfo(g, c);
List<String> carsBrands = new ArrayList<String>(carsDetails.keySet());
ItemClass adapter = new ItemClass(context, carsDetails, carsBrands);
ExpandableListView list = (ExpandableListView) view.findViewById(R.id.expandList);
list.setAdapter(adapter);
}}
but when i ran my app, i get error that i don't know why in line of:
ExpandableListView list = (ExpandableListView) view.findViewById(R.id.expandList);
i'd appreciate to help me.
Your fragment's view hierarchy is not inflated automatically just because you created an instance of your fragment, as you do in ClickButton. The onCreateView() method that has to be called first in order to inflate your views is part of the fragment's lifecycle. You should let Android instantiate your fragment, and acquire it's instance through the FragmentManager.
This tutorial explains basics about fragments very well.
Related
I want to move some data from my Mainactivity to a Fragment...which is inside a tab fragment (which handles a SectionPagerAdapter)....which is inside a fragment in Mainactivity2.
I feel its too complicated and cant get it done.
GameEndedActivity (See wrong and correct variable...these are to be transferred)
public class GameEndedActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_game_ended);
int correct = getIntent().getIntExtra("correct", 0);
int wrong = getIntent().getIntExtra("wrong", 0);
}
}
TabFragment
public class TabFragment extends Fragment {
private int tabsCount;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.activity_tab, container, false);
if(this.getContext() instanceof ChallengeOverviewActivity){
tabsCount = 2;
} else {
tabsCount = 3;
}
SectionsPagerAdapter sectionsPagerAdapter = new SectionsPagerAdapter(this.getContext(), getFragmentManager(), tabsCount);
ViewPager viewPager = view.findViewById(R.id.view_pager);
viewPager.setAdapter(sectionsPagerAdapter);
TabLayout tabs = view.findViewById(R.id.tabs);
tabs.setupWithViewPager(viewPager);
return view;
}
}
ResultFragment (Transfer data here - wrong and correct variables)
public class ResultDetailsFragment extends Fragment {
private TextView tvWrong, tvCorrect;
private AnswerListener answerListener;
public interface AnswerListener {
public void correct(int i);
public void wrong(int i);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_result_details, container, false);
tvCorrect = view.findViewById(R.id.tvCorrect);
tvWrong = view.findViewById(R.id.tvWrong);
return view;
}
#Override
public void onAttach(#NonNull Context context) {
super.onAttach(context);
if (context != null) {
answerListener = (AnswerListener) context;
}
}
}
One way to do this is the add arguments to the fragment when you create an instance of it. In your activity when you create the fragment you want to attach you add some arguments to it. These arguments can then be accessed from the fragments onCreate method.
Just do this same thing again when you are in your fragment and create your second one.
Check this answer out which explains more in detail how to do it: https://stackoverflow.com/a/17436739/964887
I'm more googling to find how can i pass simple view as an object to fragment, but i can't.
for example in MainActivity i have simple view as :
TextView text = (TextView) findviewById(R.id.tv_text);
now i want to pass that to fragment. this below code is my attach Fragment on MainActivity
MainActivity :
public void attachFragment() {
fts = getActivity().getFragmentManager().beginTransaction();
mFragment = new FragmentMarketDetail();
fts.replace(R.id.cardsLine, mFragment, "FragmentMarketDetail");
fts.commit();
}
and this is my Fragment:
public class FragmentMarketDetail extends Fragment implements ObservableScrollViewCallbacks {
public static final String SCROLLVIEW_STATE = "scrollviewState";
private ObservableScrollView scrollViewTest;
private Context context;
private int scrollY;
public static FragmentMarketDetail newInstance() {
FragmentMarketDetail fragmentFirst = new FragmentMarketDetail();
return fragmentFirst;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_online_categories, container, false);
scrollViewTest = (ObservableScrollView) view.findViewById(R.id.scrollViewTest);
scrollViewTest.setScrollViewCallbacks(this);
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
context = getActivity().getBaseContext();
}
}
It wouldn't be good practise to pass a view that way. If you want to access the view in your activity from within your fragment class, use getActivity() to access the activity to which your fragment is attached, and from there you find your TextView.
TextView text = (TextView) getActivity().findViewById(R.id.tv_text);
How about adding a set function in your custom fragment
e.g.
public void setTextView(TextView tv){
this.tv = tv
}
and then calling it after
mFragment = new FragmentMarketDetail();
mFragment.setTextView(textView)
Find fragment by tag and invoke a function on it:
mFragment = (FragmentMarketDetail ) getActivity().getFragmentManager().findFragmentByTag(FragmentMarketDetail .class.getSimpleName());
mFragment.passTextView(textView);
Of course fragment must be added to backstack.
I created a tabbed app where the main acitvity contains two layouts. The top layout contains the actual tabbar (which is a fragment). Underneth the content layout contains another fragments depending on which tabbar button the user has clicked. In order to stay compatible with older android versions I use android.support.v4.app.Fragment.
So, in the tabbar menu I added two buttons and each button triggers another fragment in the content. This is what the code looks like:
public class TabbarMenuFragment extends Fragment implements View.OnClickListener {
LiveFragment liveFragment;
OddsFragment oddsFragment;
FragmentTransaction fragmentTransaction;
Button liveButton;
Button oddsButton;
public TabbarMenuFragment() {}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
liveFragment = new LiveFragment();
oddsFragment = new OddsFragment();
fragmentTransaction = getFragmentManager().beginTransaction().add(R.id.content_view, oddsFragment);
fragmentTransaction.commit();
View rootView = (View) inflater.inflate(R.layout.tabbar_menu, container, false);
liveButton = (Button) rootView.findViewById(R.id.liveButton);
liveButton.setOnClickListener(this);
oddsButton = (Button) rootView.findViewById(R.id.oddsButton);
oddsButton.setOnClickListener(this);
return rootView;
}
public void updateUIInTabs() {
liveFragment.updateUI();
}
#Override
public void onClick(View v) {
if(v == liveButton) {
fragmentTransaction = getFragmentManager().beginTransaction().replace(R.id.content_view, liveFragment);
fragmentTransaction.commit();
}
if(v == oddsButton) {
fragmentTransaction = getFragmentManager().beginTransaction().replace(R.id.content_view, oddsFragment);
fragmentTransaction.commit();
}
updateUIInTabs();
}
}
The important thing is that the liveFragment is a Fragment that contains a ListView:
public class LiveFragment extends Fragment {
LiveMainAdapter adapter;
ListView list;
LayoutInflater inflater;
View rootView;
public LiveFragment() {}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
this.inflater = inflater;
rootView = (View) inflater.inflate(R.layout.live_fragment, container, false);
adapter = new LiveMainAdapter(inflater);
list = (ListView) rootView.findViewById(R.id.live_fragment_ListView);
list.setAdapter(adapter);
list.setDivider(null);
list.setDividerHeight(0);
return rootView;
}
public void updateUI() {
if(list != null) {
list.invalidate();
adapter.createRowObjects();
adapter.notifyDataSetChanged();
}
}
}
The oddsFragment is so far just a dummy with a TextView:
public class OddsFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = (View) inflater.inflate(R.layout.odds_fragment, container, false);
return rootView;
}
}
Now there are two settings which are important:
First:
As described above: I start the app and the oddsFragment is initally shown. Now, when I click on the liveFragment button the liveFragment's ListView is not updated.
Clicking again on the button for oddsFragment the oddsFragment is properly shown. Clicking back to liveFragment I get nothing - no ListView is shown.
The second setting:
Is exactly the same as the first, but instead I set the liveFragment as the intial view that is in TabbarMenuFragment I replace:
fragmentTransaction = getFragmentManager().beginTransaction().add(R.id.content_view, oddsFragment);
with
fragmentTransaction = getFragmentManager().beginTransaction().add(R.id.content_view, liveFragment);
Then the ListView is properly shown and the data in the list view is updated and displayed correctly. However, if I click on oddsFragement and then again on liveFragement the ListView has disappeared.
I already tried different things for over two hours now and I'm pretty desperated because I have not clue what might be the reason for this wired behaviour.
Anybody got an idea what is going on here?
Give this a try...
In your LiveFragment add a Handler and a Runnable and update the UI from your Runnable.
Handler handler = new Handler();
Runnable updater = new Runnable()
{
public void run()
{
if(list != null) {
list.invalidate();
adapter.createRowObjects();
adapter.notifyDataSetChanged();
}
}
};
and then change your updateUI() method in LiveFragment
public void updateUI()
{
handler.post(updater);
}
public class MainActivity extends Activity implements MainMenuFragment.OnMainMenuItemSelectedListener {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager
.beginTransaction();
// add menu fragment
MainMenuFragment myFragment = new MainMenuFragment();
fragmentTransaction.add(R.id.menu_fragment, myFragment);
//add content
DetailPart1 content1= new DetailPart1 ();
fragmentTransaction.add(R.id.content_fragment, content1);
fragmentTransaction.commit();
}
public void onMainMenuSelected(String tag) {
//next menu is selected replace existing fragment
}
I have a need to display two list views side by side, menu on left and its content on right side. By default, the first menu is selected and its content is displayed on right side. The Fragment that displays content is as below:
public class DetailPart1 extends Fragment {
ArrayList<HashMap<String, String>> myList = new ArrayList<HashMap<String, String>>();
ListAdapter adap;
ListView listview;
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if(savedInstanceState!=null){
myList = (ArrayList)savedInstanceState.getSerializable("MYLIST_obj");
adap = new LoadImageFromArrayListAdapter(getActivity(),myList );
listview.setAdapter(adap);
}else{
//get list and load in list view
getlistTask = new GetALLListTasks().execute();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.skyview_fragment, container,false);
return v;
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putSerializable("MYLIST_obj", myList );
}
}
The onActivityCreated and onCreateView are called twice. There are many examples out there using fragments. Since I am beginner in this subject, I am unable relate the example with my problem. I need a fool proof way to handle orientation change. I have NOT declared android:configChanges in manifest file. I need the activity destroy and recreate so that I can use different layout in landscape mode.
You are creating a new fragment every time you turn the screen in your activity onCreate(); But you are also maintaining the old ones with super.onCreate(savedInstanceState);. So maybe set tag and find the fragment if it exists, or pass null bundle to super.
This took me a while to learn and it can really be a pain when you are working with stuff like viewpager.
I'd recommend you to read about fragments an extra time as this exact topic is covered.
Here is an example of how to handle fragments on a regular orientation change:
Activity:
public class MainActivity extends FragmentActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
TestFragment test = new TestFragment();
test.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction().replace(android.R.id.content, test, "your_fragment_tag").commit();
} else {
TestFragment test = (TestFragment) getSupportFragmentManager().findFragmentByTag("your_fragment_tag");
}
}
}
Fragment:
public class TestFragment extends Fragment {
public static final String KEY_ITEM = "unique_key";
public static final String KEY_INDEX = "index_key";
private String mTime;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_layout, container, false);
if (savedInstanceState != null) {
// Restore last state
mTime = savedInstanceState.getString("time_key");
} else {
mTime = "" + Calendar.getInstance().getTimeInMillis();
}
TextView title = (TextView) view.findViewById(R.id.fragment_test);
title.setText(mTime);
return view;
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putString("time_key", mTime);
}
}
A good guideline about how to retain data between orientation changes and activity recreation can be found in android guidelines.
Summary:
make your fragment retainable:
setRetainInstance(true);
Create a new fragment only if necessary (or at least take data from it)
dataFragment = (DataFragment) fm.findFragmentByTag("data");
// create the fragment and data the first time
if (dataFragment == null) {
I am trying to show a FragmentDialog ( created and shown as a dialog NOT added as content in a view hierarchy) where there is a ViewPager whose content is given by a FragmentPagerAdapter (provides Fragments consisting of an image).
The code works perfect when showing ViewPager + FragmentPagerAdapter from a FragmentActivity, but get the following exception when doing it from a FragmentDialog:
"IllegalArgumentException: No view found for id 0x7f040077 for fragment SimpleFragment..."
Here is my code:
A SherlockFragmentActivity with a button to create and show the dialog.
public class BorrameActivity extends SherlockFragmentActivity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.one_act);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View arg0) {
showTheDialog();
}});
}
private void showTheDialog(){
AchGalleryDialog newFragment = AchGalleryDialog.newInstance(achs);
newFragment.show(getSupportFragmentManager(), "dialog");
}
The FragmentDialog:
public class AchGalleryDialog extends DialogFragment{
public AchGalleryDialog(){
}
public static AchGalleryDialog newInstance(){
AchGalleryDialog f = new AchGalleryDialog();
return f;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.dialog_user_result, container);
getDialog().setTitle("Hola tronco");
//content to show in the fragments
int[] images = new int[]{R.drawable.d1, R.drawable.d2, R.drawable.d3};
ViewPager pager = (ViewPager) view.findViewById(R.id.pager);
MyFragmentAdapter adapter = new MyFragmentAdapter(getFragmentManager(),images);
pager.setAdapter(adapter);
return view;
}
}
This is the very simple MyFragmentPagerAdapter,
I put only the getItem() method, and nullPointer checks:
#Override
public Fragment getItem(int position) {
return MySimpleFragment.newInstance(images[position]);
}
And finally SimpleFragment:
public class SimpleFragment extends Fragment{
int id;
public static SimpleAchFragment newInstance(int imgId){
SimpleFragment f = new SimpleFragment();
Bundle args = new Bundle();
args.putLong(ID_BUNDLE, imgId);
f.setArguments(args);
return f;
}
public SimpleAchFragment(){
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.id = getArguments() != null ? getArguments().getInt(ID_BUNDLE) : 0;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.simple_fragment, container, false);
FragmentActivity mAct = getActivity();
ImageView img = (ImageView) v.findViewById(R.id.image);
img.setImageDrawable(mAct.getResources().getDrawable(id));
return v;
}
}
More info, if the content passed to the adapter ( an int array with 3 ints) has length zero, then the adapter doesn't try to create any Fragment so dialogs appears correctly but empty (as expected).
The Exception is thrown at SimpleFragment.onCreateView() at the time of inflating.
The id referenced in the exception (as not found) correspond to ViewPager 's id, with is properly defined in R.layout.simple_fragment.
I have try also to build the Dialog with an AlertDialog.builder and also directly with Dialog() contructor, but get the same behaviour.
Try this:
In class AchGalleryDialog
MyFragmentAdapter adapter = new MyFragmentAdapter(getChildFragmentManager(),images);
instead of
MyFragmentAdapter adapter = new MyFragmentAdapter(getFragmentManager(),images);
Because of this:
http://developer.android.com/about/versions/android-4.2.html#NestedFragments
Hope this will help!