Develop Reference

Listen Dialog Positive button click in each ViewPager fragment

I'm testing a function of listening the AlertDialog button click (Positive & Neutral) in each ViewPager fragment. And I am using the Interface method right now but getting some troubles.
So the structure is like this, I have an AlertDialog created by DialogFragment, and I put a ViewPager with two fragments into this DialogFragment. My goal is, when I click on the Positive button on the AlertDialog, I want some methods inside those two ViewPager fragments get called so that I can collect the data on those fragments.
Now the problem is, only the second fragment responses, I don't know why.
Here are the codes:
I created an Interface file
public interface Communicator {
void onConfirmClick();
}
I have a DialogFragment
public class MainDialogFragment extends DialogFragment {
View dialogLayout;
Communicator communicator;
#Override
public void onAttachFragment(Fragment childFragment) {
communicator = (Communicator) childFragment;
}
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return dialogLayout;
}
#NonNull
#Override
public Dialog onCreateDialog(#Nullable Bundle savedInstanceState) {
AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(getActivity());
dialogLayout = getActivity().getLayoutInflater().inflate(R.layout.dialog_main, null);
ViewPager viewPager = dialogLayout.findViewById(R.id.main_viewPager);
final MainPagerAdapter adapter = new MainPagerAdapter(getChildFragmentManager());
viewPager.setAdapter(adapter);
dialogBuilder.setView(dialogLayout);
dialogBuilder.setPositiveButton("Confirm", null);
dialogBuilder.setNegativeButton("Cancel", null);
dialogBuilder.setNeutralButton("Change", null);
final AlertDialog dialog = dialogBuilder.create();
dialog.setOnShowListener(new DialogInterface.OnShowListener() {
#Override
public void onShow(DialogInterface dialogInterface) {
dialog.getButton(DialogInterface.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
communicator.onConfirmClick();
}
});
dialog.getButton(DialogInterface.BUTTON_NEUTRAL).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Toast.makeText(view.getContext(), "Change click!!", Toast.LENGTH_SHORT).show();
}
});
}
});
return dialog;
}
}
My fragment A
public class MainFragmentA extends Fragment implements Communicator{
View rootView;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.fragment_a, container, false);
return rootView;
}
#Override
public void onConfirmClick() {
Toast.makeText(getContext(), "Fragment A!!", Toast.LENGTH_SHORT).show();
}
}
My fragment B
public class MainFragmentB extends Fragment implements Communicator{
View rootView;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.fragment_b, container, false);
return rootView;
}
#Override
public void onConfirmClick() {
Toast.makeText(getContext(), "Fragment B!!", Toast.LENGTH_SHORT).show();
}
}
My ViewPager adapter used inside DialogFragment
public class MainPagerAdapter extends FragmentPagerAdapter {
public MainPagerAdapter(FragmentManager fragmentManager) {
super(fragmentManager);
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new MainFragmentA();
case 1:
return new MainFragmentB();
default:
throw new IllegalArgumentException("Wrong position!!");
}
}
#Override
public int getCount() {
return 2;
}
}
My MainActivity
public class MainActivity extends AppCompatActivity{
Button showDialogButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
showDialogButton = findViewById(R.id.main_show_dialog_button);
showDialogButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
MainDialogFragment mainDialogFragment = new MainDialogFragment();
mainDialogFragment.show(getSupportFragmentManager(), "mainDialogFragment");
}
});
}
}
Anyone can help? I'll so appreciate that!!!

Use a collection of some sort of Communicator interfaces instead of a single one. You're overwriting the communicator every time a child fragment is attached.
public class MainDialogFragment extends DialogFragment {
View dialogLayout;
List<Communicator> communicators = new ArrayList<>();
#Override
public void onAttachFragment(Fragment childFragment) {
communicators.add((Communicator) childFragment);
}
// all the other things from the MainDialogFragment...
}
And in the BUTTON_POSITIVE callback iterate through the list.
dialog.getButton(DialogInterface.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
for (Communicator communicator : communicators) {
communicator.onConfirmClick();
}
}
});

Only the communicator from the second fragment works
This is because you have two different instances of communicator in each of your fragments. As you are setting up the ViewPager, the second fragment is the last one that is being attached with the parent fragment. Hence, the communicator that you are initializing inside the onAttachFragment function of your MainDialogFragment class, is storing the reference from the second fragment only as this was the last one to be attached here.
In your case, I would rather suggest a very simple implementation using the lifecycle functions of the Fragment. Just take a public static variable in your MainDialogFragment class which will indicate if the okay button was clicked or not. And then check the value of that variable from each of your Fragment class inside the onResume function and perform the tasks accordingly. To get an idea of the implementation, please check the following.
Get a variable in your MainDialogFragment class like the following.
public static boolean isDialogOkayClicked = false; // Default false
Now in your MainFragmentA, implement the onResume function and check the value from the MainDialogFragment. Take the actions accordingly.
public class MainFragmentA extends Fragment implements Communicator{
View rootView;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.fragment_a, container, false);
return rootView;
}
#Override
protected void onResume() {
super.onResume();
if(MainDialogFragment.isDialogOkayClicked)
doSomething();
}
#Override
public void onConfirmClick() {
Toast.makeText(getContext(), "Fragment A!!", Toast.LENGTH_SHORT).show();
}
}
Do the same thing for your other fragment.
Hope that helps!

Use a view from a fragment in main activity

I'm pretty new in android development and I have some questions about communication between fragments and main activity.
I didn't success to solve my problem in my particular case. What I want to do is to modify the alpha of a view inside a fragment (something like a card) when scrolling from one fragment to the one with this view. I tried different things but I failed (null pointer exception), you can see some experiments in a comment. Here is my code and my architecture:
Fragment with the view:
public class VideoviewFragment extends BaseFragment {
/* public View card;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootview = inflater.inflate(R.layout.fragment_videoview, container, false);
card = (View) rootview.findViewById(R.id.card_video);
return rootview;
}
public void setalphacard(float value){
card.setAlpha(value);
}*/
public static VideoviewFragment create() {
return new VideoviewFragment();
}
#Override
public int getLayoutResId() {
return R.layout.fragment_videoview;
}
#Override
public void inOnCreateView(View root, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
}
}
Base fragment:
public abstract class BaseFragment extends Fragment {
private View mRoot;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
mRoot = inflater.inflate(getLayoutResId(), container, false);
inOnCreateView(mRoot, container, savedInstanceState);
return mRoot;
}
#LayoutRes
public abstract int getLayoutResId();
public abstract void inOnCreateView(View root, #Nullable ViewGroup container,#Nullable Bundle savedInstanceState);
}
Main Activity:
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Viewpager
final ViewPager viewPager = (ViewPager) findViewById(R.id.am_view_pager);
final MainPagerAdapter adapter = new MainPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(adapter);
// tabview et viewpager
viewPager.setCurrentItem(1);
// Changement couleurs swipe
viewPager.setBackgroundColor(Color.rgb(135,206,250));
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
if(position == 1) {
viewPager.setBackgroundColor((Integer) new ArgbEvaluator().evaluate(positionOffset, Color.rgb(135,206,250),Color.rgb(240,15,45)));
//videoviewFragment.setalphacard(positionOffset);
}
if(position == 0) {
viewPager.setBackgroundColor((Integer) new ArgbEvaluator().evaluate(positionOffset, Color.TRANSPARENT,Color.rgb(135,206,250)));
}
}
#Override
public void onPageSelected(int position) {
}
#Override
public void onPageScrollStateChanged(int state) {
}
});
}
}
Adapter:
public class MainPagerAdapter extends FragmentPagerAdapter {
public MainPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
switch (position){
case 0:
return CameraFragment.create();
case 1:
return OptionFragment.create();
case 2:
return VideoviewFragment.create();
}
return null;
}
#Override
public int getCount() {
return 3;
}
}
XML VideoviewFragment
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/relativeLayout0"
android:layout_width="match_parent"
android:layout_height="match_parent">
<View
android:id="#+id/card_video"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="70dp"
android:background="#drawable/card_background_video"/>
</RelativeLayout>
(I know there is no instance of my fragment in this activity...)
I found few similar topics on StackOverflow like this one Use view from fragment xml file, but I'm doing something wrong...
Thanks for your help!

can not pass data from on fragment to other in ViewPager

I have an Activity with viewpager in one page should be EditText and other page be the TextView, get data from first fragment to show in second view but I'm struggling because of lack of knowledge, I have Main Activity as
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
viewPager.setAdapter(new MyPagerAdapter(getSupportFragmentManager()));
}
private class MyPagerAdapter extends FragmentPagerAdapter {
public MyPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int pos) {
switch(pos) {
case 0: return EditFragment.newInstance("FirstFragment, Instance 1");
case 1: {
Log.e("TAG", " is " + new EditFragment().getTag());
return PreviewFragment.newInstance(new EditFragment().getTag());
}
default: return EditFragment.newInstance("ThirdFragment, Default");
}
}
#Override
public int getCount() {
return 2;
}
}
}
main layout is
<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/viewpager"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
EditFragment is
public class EditFragment extends Fragment {
public EditFragment(){}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_editor, container, false);
EditText tv = (EditText) v.findViewById(R.id.content);
tv.setText(getArguments().getString("msg"));
return v;
}
public static EditFragment newInstance(String text) {
EditFragment f = new EditFragment();
Bundle b = new Bundle();
b.putString("msg", text);
f.setArguments(b);
return f;
}
}
PreviewFragment
public class PreviewFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_markdown, container, false);
TextView tvView = (TextView) v.findViewById(R.id.markdownView);
tvView.loadMarkdown(getArguments().getString("msg"));
return v;
}
public static PreviewFragment newInstance(String text) {
PreviewFragment f = new PreviewFragment();
Bundle b = new Bundle();
b.putString("msg", text);
f.setArguments(b);
return f;
}
}
there I do not know how to pass data from EditFragment to PreviewFragment, please help.
I'm newbie to Fragments please help me.
UPDATE
I have changed
public class PreviewFragment extends Fragment {
private TextView textView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_markdown, container, false);
textView = (TextView) v.findViewById(R.id.title);// initialized here
return v;
}
public void b_updateText(String t){
Log.e("LOAD TXT", t);// Here I can get data Data is available
textView.setText(t); // but Here I get NPE, don't know why.
}
}
but Here I get NPE, don't know why.
and EditFragment is
public class EditFragment extends Fragment {
public EditFragment(){}
private static Bundle bundle = null;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_editor, container, false);
final EditText tv = (EditText) v.findViewById(R.id.content);
final PsgerActivity mainActivity = ( PsgerActivity) getActivity();
mainActivity.message= tv.getText().toString();
tv.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
#Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
bundle = new Bundle();
bundle.putString("md", tv.getText().toString());
Log.e("BUNDLE", bundle.getString("md"));// Data is available
}
#Override
public void afterTextChanged(Editable editable) {
}
});
return v;
}
public static EditFragment newInstance() {
EditFragment f = new EditFragment();
f.setArguments(bundle);
return f;
}
}
MainActivity is
public class MainActivity extends AppCompatActivity {
public String message;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
viewPager.setAdapter(new MyPagerAdapter(getSupportFragmentManager()));
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
if (position == 1) {
PreviewFragment fragmentB = new PreviewFragment();
EditFragment ef = EditFragment.newInstance();
try{
Log.e("ACTIVITY", ef.getArguments().getString("md"));// Data is available
} catch (Exception e){
e.printStackTrace();
}
fragmentB.b_updateText(ef.getArguments().getString("md"));
}
}
#Override
public void onPageSelected(int position) {
}
#Override
public void onPageScrollStateChanged(int state) {
}
});
}
private class MyPagerAdapter extends FragmentPagerAdapter {
public MyPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int pos) {
switch(pos) {
case 0: return EditFragment.newInstance();
case 1: return new PreviewFragment();
default: return EditFragment.newInstance();
}
}
#Override
public int getCount() {
return 2;
}
}
}
but Here I get NPE, don't know why.

Have you had a chance go through android docs?
Communicating with Other Fragments
Of course you can use Otto or EventBus library.
And also have a look at this answer.

Create a variable in MainActivity and access that variable from fragment through
MainActivity mainActivity = ( MainActivity) getActivity();
mainActivity.message="Hai from EditFragment"
Check out the below code:
public class MainActivity extends AppCompatActivity {
public String message;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
viewPager.setAdapter(new MyPagerAdapter(getSupportFragmentManager()));
}
private class MyPagerAdapter extends FragmentPagerAdapter {
public MyPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int pos) {
switch(pos) {
case 0: return EditFragment.newInstance("FirstFragment, Instance 1");
case 1: {
Log.e("TAG", " is " + new EditFragment().getTag());
return PreviewFragment.newInstance(new EditFragment().getTag());
}
default: return EditFragment.newInstance("ThirdFragment, Default");
}
}
#Override
public int getCount() {
return 2;
}
}
}
EditFragment is
public class EditFragment extends Fragment {
public EditFragment(){}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_editor, container, false);
EditText tv = (EditText) v.findViewById(R.id.content);
tv.setText(getArguments().getString("msg"));
MainActivity mainActivity = ( MainActivity) getActivity();
mainActivity.message="Hai from EditFragment"
//store data through message variable inside activity
return v;
}
}
PreviewFragment
public class PreviewFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_markdown, container, false);
TextView tvView = (TextView) v.findViewById(R.id.markdownView);
MainActivity mainActivity = ( MainActivity) getActivity();
tvView.loadMarkdown(mainActivity.message);// get data through message variable of main activity
return v;
}
}

With FragmentManager, we can access another fragment from our current fragment by calling findFragmentByTag(<tag of target fragment>).
// First Fragment, from we're sending data
public class MyFragmentA extends Fragment {
EditText A_input;
Button A_enter;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View myFragmentView = inflater.inflate(R.layout.fragment_a, container, false);
A_input = (EditText)myFragmentView.findViewById(R.id.a_input);
A_enter = (Button)myFragmentView.findViewById(R.id.a_enter);
A_enter.setOnClickListener(A_enterOnClickListener);
return myFragmentView;
}
OnClickListener A_enterOnClickListener = new OnClickListener(){
#Override
public void onClick(View arg0) {
String textPassToB = A_input.getText().toString();
String TabOfFragmentB = ((MainActivity)getActivity()).getTabFragmentB();
MyFragmentB fragmentB = (MyFragmentB)getActivity()
.getSupportFragmentManager()
.findFragmentByTag(TabOfFragmentB);
fragmentB.b_updateText(textPassToB);
Toast.makeText(getActivity(),
"text sent to Fragment B:\n " + TabOfFragmentB,
Toast.LENGTH_LONG).show();
}};
}
// Second Fragment, where we'll get data
public class MyFragmentB extends Fragment {
TextView b_received;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View myFragmentView = inflater.inflate(R.layout.fragment_b, container, false);
b_received = (TextView)myFragmentView.findViewById(R.id.b_received);
String myTag = getTag();
((MainActivity)getActivity()).setTabFragmentB(myTag);
Toast.makeText(getActivity(),
"MyFragmentB.onCreateView(): " + myTag,
Toast.LENGTH_LONG).show();
return myFragmentView;
}
public void b_updateText(String t){
b_received.setText(t);
}
}

Called method current selected fragment viewpager from parent activity?

Huy guys, I have problem with my App. I created viewpager with some fragment.
this my viewpager ini my parent activity
private int current_posisition_page ;
#Override
protected v
oid onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
.....
viewpager.setAdapter(new PagePagerAdapter(getSupportFragmentManager()));
viewpager.setCurrentItem(999);
viewpager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
// This method will be invoked when a new page becomes selected.
#Override
public void onPageSelected(int position) {
current_posisition_page = position;
}
// This method will be invoked when the current page is scrolled
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
#Override
public void onPageScrollStateChanged(int state) {
}
});
.......
}
private class PagePagerAdapter extends FragmentPagerAdapter {
public PagePagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int pos) {
return PageFragment.newInstance(pos);
}
#Override
public int getCount() {
return 1000;
}
}
}
and this my fragment
public class PageFragment extends Fragment {
public static PageFragment newInstance(int page_index) {
PageFragment fragment = new PageFragment();
Bundle args = new Bundle();
args.putString(Variabel.page_index, String.valueOf(page_index));
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
page_index = getArguments().getString(Variabel.page_index);
}
activity=(MainActivity)getActivity();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.item_page, container, false);
ButterKnife.bind(this, v);
return v;
}
public void setSelectedAyat(String aya_id, String sura_name) {
surat.setText("Surat " + sura_name);
ayat.setText("Ayat " + aya_id);
}
}
Now I called method current selected fragment viewpager from parent activity:
PageFragment page = (PageFragment) adapter.getItem(current_posisition_page);
page.setSelectedAyat(aya_id, sura_name);
but I get Error :
java.lang.ClassCastException: java.lang.Integer cannot be cast to
com.ad.alquran.kemendag.fragment.PageFragment
in line : PageFragment page = (PageFragment) adapter.getItem(current_posisition_page);
so how to fix it ? thanks

Probably this line causing issue:
viewpager.setAdapter(new PagePagerAdapter(getSupportFragmentManager()));
Because adapter object for calling getItem method but in ViewPager setAdapter method passing different object of PagePagerAdapter class:
adapter=new PagePagerAdapter(getSupportFragmentManager());
viewpager.setAdapter(adapter);
and also make sure calling getItem method after setting adapter for ViewPager.
EDIT:
java.lang.NullPointerException: Attempt to invoke virtual method 'void
android.widget.TextView.setText(java.lang.CharSequence)' on a null
object reference
Because not initializing surat and ayat. do it as:
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.item_page, container, false);
//...
surat=(TextView)v. findViewById(R.id.<surat_id_in_xml>);
ayat=(TextView)v. findViewById(R.id.<ayat_id_in_xml>);
return v;
}

Unable to call Fragment's Method from Parent View

I am trying to call a Fragment's public Method from its Parent View and I followed this, this and these questions on Stack. However the method I need is not avilable when I try to call it from the Parent view.
Here's my code:
Fragment:
public class FirstTabView extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.activity_first_tab_view, container, false);
return rootView;
}
//The method I need to call
public void PostStuff(String caption){
}
}
Parent View: (Which contains the Main View Pager)
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_view);
pager = (ViewPager) findViewById(R.id.mainpager);
mAdapter = new HomePagerAdapter(getSupportFragmentManager());
pager.setAdapter(mAdapter);
pager.setOffscreenPageLimit(4);
//Getting the Fragment's Tag. o is the Pager's Fragment index. i.e.: The first fragment
String fragment_tag = "android:switcher:" + pager.getId() + ":" + 0;
FirstTabView fragment = (FirstTabView) getSupportFragmentManager().findFragmentByTag(fragment_tag);
fragment. <This is where I need to call the method and pass the parameter> ();
//The method however doesn't appear when I try to reference it
}
Am I calling the Fragment's method correctly from my Parent View? What am I doing wrong?
EDIT
This is the adapter that I used to push the Fragments:
public class HomePagerAdapter extends FragmentPagerAdapter {
public HomePagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
switch (index) {
case 0:
return new FirstTabView();
case 1:
return new SecondTabView();
case 2:
return new ThirdTabView();
case 3:
return new FourthTabView();
case 4:
return new FifthTabView();
}
return null;
}
#Override
public int getCount() {
// get item count - equal to number of tabs
return 5;
}
}

You can save a reference of the FirstTabView to your MainActivity, then call the method of the fragment.
FirstTabView
public class FirstTabView extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.activity_first_tab_view, container, false);
return rootView;
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
//set this fragment to your MainActivity
MainActivity mainActivity = (MainActivity)getActivity();
mainActivity.setFirstTabView(this);
}
//The method I need to call
public void PostStuff(String caption){
}
}
MainActivity
private FirstTabView firstTabView;
#Override
public void onCreate(Bundle bundle) {
........
if(firstTabView != null) {
firstTabView.PostStuff("Hello World");
}
}
public void setFirstTabView(FirstTabView firstTabView){
this.firstTabView = firstTabView
}