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When click button inside fragment I want to go to another fragment in the parent TabLayout

I have a MainActivity, Contains TabLayout having two fragments FA, FB
The First Fragment FA having another Tablayout contains 2 fragments FAA, FAB
I have a button inside FAA, i want when i click on it, it send me to FB which already inside the parent TabLayout
I tried many solutions but it didn't help, any suggestions?
#OnClick(R.id.frag_timeline_fab_faa)
public void goToFBFromFAA(View view) {
// Code shoud be here
}

The way to do this is through interfaces.Here is a similar question I found
In fragment FAA:
public interface OnFragmentInteractionListener {
void onFragmentInteraction(Param param);
}
Then in your parent fragment you need to implement that interface:
public class FA extends Fragment implements
FAA.OnFragmentInteractionListener {
#Override
public void onFragmentInteraction(Param param) {
//Your code here
}
}

ViewPager Fragments are not recreated after FragmentTransaction.replace() followed by back button

I am trying to implement saving and restoring state, but I am running into problems when replacing the main Fragment with a PreferenceFragment and then hitting the back button. My main Fragment consists of a ViewPager with a FragmentPagerAdapter with 3 Fragments to swipe through. None of the Fragment.onCreateView() callbacks for my 3 Fragments are invoked after hitting the back button. I have tried all the solutions I have come over here on SO, but I have not been able to resolve the issue.
Another possibly important thing to note is that the data for my 3 ViewPager Fragments are stored in separate classes which are instanced and accessible through the Activity. The 3 Fragments all contain RecyclerViews for listing a fair amount of data. This is done for cleanliness, but also so that these data persist in the Activity. This is probably not an issue, since it works fine when starting the app, but also since the main issue is that my Fragments are not recreated.
Unexpected behavior:
On application creation, everything works fine, but when I replace my main Fragment (containing a ViewPager with a FragmentPagerAdapter) with another one and then pressing the back button, the Fragments in the ViewPager are not recreated. The onCreateView() of my main Fragment is called.
Questions:
What am I missing? Is there some other callbacks that should be created? Where and how should I recreate the Fragments?
What have I tried:
Changed the FragmentAdapter in use, but I should really use getSupportFragmentManager() as was the solution here.
EDIT: Use of erroneous FragmentManager actually was the source of my troubles. See my answer below.
Add
#Override public int getItemPosition(Object object) {return POSITION_NONE;} to the FragmentPagerAdapter, as suggested here.
Change from FragmentPagerAdapter to FragmentStatePagerAdapter which should not matter here, as far as I understand. The internals of FragmentStatePagerAdapter actually keeps the Fragments, but they are not rendered anew.
Add the main Fragment back using a FragmentTransaction when its onCreateView() is called and in several of the other callbacks of that Fragment, see MMMainFragment below.
Various other things.
My MainFragment class with corresponding XML layout
public class MMMainFragment extends Fragment
{
private MMViewPager mMMViewPager = null;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
// Note that this method IS called when the back button is pressed.
// I have tried setting the content back to this instance in several places.
View view = inflater.inflate(R.layout.mm_main_fragment, container, false);
// Setup ViewPager.
mMMViewPager = (MMViewPager) view.findViewById(R.id.mm_pager);
TabLayout tabLayout = (TabLayout) view.findViewById(R.id.mm_tablayout);
tabLayout.setupWithViewPager(mMMViewPager);
return view;
}
public MMViewPager getMMViewPager()
{
return mMMViewPager;
}
}
mm_main_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<android.support.design.widget.TabLayout
android:id="#+id/mm_tablayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="scrollable" />
<com.mycompany.myapp.gui.mmpager.MMViewPager
android:id="#+id/mm_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
</LinearLayout>
Then, in Activity.onCreate() i simply do:
// Insert Main Fragment.
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.mm_content_frame, new MMMainFragment())
.commit();
where mm_content_frame is a FrameLayout where I replace and remove Fragments. Then, when a button to view the preferences are pushed, I run the following snippet below in the Activity. I add this Fragment to the backstack to be able to use the back button.
public void showSettingsFragment()
{
getSupportActionBar().setTitle(getString(R.string.mm_drawer_settings));
getSupportFragmentManager().beginTransaction()
.replace(R.id.mm_content_frame, new MMPreferencesFragment(), FragmentConstants.SETTINGS_FRAGMENT_TAG)
.addToBackStack(null)
.commit();
}
The MMViewPager clas:
public class MMViewPager extends ViewPager
{
private MMActivity mMMActivity;
private MMPagerAdapter mMMPagerAdapter;
public MMViewPager(Context context, AttributeSet attrs)
{
super(context, attrs);
mMMActivity = (MMActivity) context;
mMMPagerAdapter = new MMPagerAdapter(mMMActivity.getSupportFragmentManager(), mMMActivity);
this.setOffscreenPageLimit(PagerConstants.OFFSCREEN_PAGE_LIMIT);
this.setAdapter(mMMMPagerAdapter);
this.setCurrentItem(PagerConstants.PAGE_FILTER_RECIPES);
}
}
The MMPagerAdapter class, currently a FragmentStatePagerAdapter:
public class MMPagerAdapter extends FragmentStatePagerAdapter
{
private MMActivity mMMActivity;
public MMPagerAdapter(FragmentManager fragmentManager, MMActivity mmActivity)
{
super(fragmentManager);
mMMActivity = mmActivity;
}
#Override
public Fragment getItem(int position)
{
switch (position)
{
case PagerConstants.PAGE_FILTER_RECIPES:
return new FilteredRecipesFragment();
case PagerConstants.PAGE_SELECTED_RECIPES:
return new SelectedRecipesFragment();
case PagerConstants.PAGE_SHOPPING_LIST:
return new ShoppingListFragment();
default:
return null;
}
}
#Override
public int getCount()
{
return PagerConstants.NUMBER_OF_PAGES; // 3
}
#Override
public CharSequence getPageTitle(int position)
{
switch (position)
{
case PagerConstants.PAGE_FILTER_RECIPES:
return mMMActivity.getResources().getString(R.string.mm_title_recipe_filter_fragment);
case PagerConstants.PAGE_SELECTED_RECIPES:
return mMMActivity.getResources().getString(R.string.mm_title_selected_recipes_fragment);
case PagerConstants.PAGE_SHOPPING_LIST:
return mMMActivity.getResources().getString(R.string.mm_title_shopping_list_fragment);
default:
return "Tab";
}
}
}
For reference, here is also the main layout of the Activity:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/mm_drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Source: http://developer.android.com/training/implementing-navigation/nav-drawer.html -->
<!-- The main content view -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Source: http://android-developers.blogspot.in/2014/10/appcompat-v21-material-design-for-pre.html -->
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/mm_toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="?attr/actionBarSize"
android:layout_alignParentTop="true"
style="#style/MMActionBar"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" />
<!-- The FrameLayout where I replace Fragments -->
<FrameLayout
android:id="#+id/mm_content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#id/mm_toolbar"/>
</RelativeLayout>
<ListView
android:id="#+id/mm_drawer_listview"
android:layout_width="260dp"
android:layout_height="match_parent"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:paddingStart="16dp"
android:layout_gravity="start"
android:choiceMode="singleChoice"
android:divider="#android:color/transparent"
android:dividerHeight="0dp"
android:background="#color/mm_white" />
</android.support.v4.widget.DrawerLayout>

After struggling with this for a few days I realized that the problem actually was that I passed the wrong FragmentManager to the ViewPager. It is indeed the FragmentManager returned by Fragment.getChildFragmentManager() that should be used. This makes sense, since it is the Fragment itself that stores the state of the child Fragments in the ViewPager. I am not sure why I couldn't make that work before, but now the LifeCycle of the app works fine with the following setup in my main Fragment's onCreate() method:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.mm_main_fragment, container, false);
mMMActivity = (MMActivity) container.getContext();
mMMActivity.getSupportActionBar().setTitle(getString(R.string.mm_toolbar_title_main_fragment));
// Setup ViewPager.
mViewPager = (ViewPager) view.findViewById(R.id.mm_pager);
mAdapter = new MMPagerAdapter(getChildFragmentManager(), mMMActivity); // <-- This is the key
mViewPager.setAdapter(mAdapter);
mViewPager.setOffscreenPageLimit(PagerConstants.OFFSCREEN_PAGE_LIMIT);
mViewPager.setCurrentItem(PagerConstants.PAGE_FILTER_RECIPES);
// Setup TabLayout.
TabLayout tabLayout = (TabLayout) view.findViewById(R.id.mm_tablayout);
tabLayout.setupWithViewPager(mViewPager);
return view;
}
This was also the solution of another question. As a side note, I use this solution to get the Fragments in my ViewPager and it works just fine with the LifeCycle.
Test Application:
In the research of this issue I created a test application for this. The ones interested can clone it from here. It has ugly colors.

As far as, I understand you have solved your problem. I have faced a quite similar issue in the past. Maybe this help others trying something similar.
The thing that helped me in order to retain my fragment state was to replace the
#Override
public Fragment getItem(int position)
{
switch (position)
{
case PagerConstants.PAGE_FILTER_RECIPES:
return new FilteredRecipesFragment();
case PagerConstants.PAGE_SELECTED_RECIPES:
return new SelectedRecipesFragment();
case PagerConstants.PAGE_SHOPPING_LIST:
return new ShoppingListFragment();
default:
return null;
}
}
method of my adapter.
I change the Adapter so as to keep a HashMap of Fragment. This way the fragments are created once and then retrieved from the HashMap. Depending on your structure you can use an ArrayList instead of the HashMap.
This is done in an efficient and "smart" way of implementing getItemPosition(Object object) to return POSITION_NONE; or the proper position of the item.
I don't really remember if I had the getChildFragmentManager in the adapter or not.
I guess that I could dig into my filesystem if you need further information :)

Android : Swipe within fragment

Could anybody give me a clue in the following situation :
I have an Android 3+ app, which consists of a sofisticated set of interchangably operating activities derived from ActionBarActivity. One of them includes a set of fragments derived from Fragment, that can be selected by user by means of
getSupportFragmentManager().beginTransaction()
.replace(R.id.containerBase, FragmentX.getInstance(0))
.commit()
where
FragmentX extends Fragment {
public static FragmentX getInstance() {
FragmentX fragment = new FragmentX();
return fragment;
}
public FragmentX() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_x, container, false);
. . . . . . . .
return rootView;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
. . . . . . . .
}
}
All fragments (X, Y, Z etc) appear properly and I was happy until it became necessary to modify some fragments so that they can have several subpages, which should be swipable horizontally by user. Other fragments should stay as they are.
Which Android classes could be the optimal choice and how could they be intergrated in my app?
Any help would be highly appreciated.

The Fragment that needs to have "horizontally swipable subpages" should probably use a ViewPager of some sort. Your use case isn't completely clear but in my experience a ViewPager with another set of fragments provides a nice and flexible solution. Also, if your "child" fragments (those in the ViewPager) are essentially the same but display different data (e.g. a set of event details fragments), this fragment can also be reused. If not, you can use a switch or something similar in the ViewPager's public Fragment getItem(int position) method.
You should take a look at the FragmentStatePagerAdapter which should fit your needs, the linked page also has a nice and detailed example of how to use it. One thing to note here, since you are using fragments within fragments, the fragment which contains the ViewPager will need to use getSupportChildFragmentManager instead of the regular getSupportFragmentManager to display those fragments.

Certainly I must give some more details about my app.
public class BasePage extends ActionBarActivity implements NavigationBase.NavigationDrawerCallbacks {
private int mPage;
private NavigationBase mNavigationFragment;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
. . . . . . . .
setContentView(R.layout.activity_base);
mNavigationFragment = (NavigationBase) fragmentManager.findFragmentById(R.id.navigation_drawer);
mNavigationFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
}
private void setPage() {
switch(mPage) {
case 1:
fragmentManager.beginTransaction()
.replace(R.id.containerBase, FragmentX.getInstance())
.commit();
break;
case 2:
fragmentManager.beginTransaction()
.replace(R.id.containerBase, FragmentY.getInstance())
.commit();
break;
}
}
}
The activity_base layout looks like this:
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="app.BasePage">
<RelativeLayout
android:id="#+id/containerBase"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<fragment
android:id="#+id/navigation_drawer"
android:layout_width="#dimen/navigation_drawer_width"
android:layout_height="match_parent"
android:layout_gravity="start"
android:name="app.NavigationBase" />
</android.support.v4.widget.DrawerLayout>
User navigates through current fragments by setting mPage and calling setPage().
Now I need to modify the fragment X thus it has several subpages, whereas the fragment Y must stay as it is. Programmatically the classes FragmentX and FragmentY are identical, they display solely different user contents.
I comprehend that ViewPager must be a right solution in this scenario. My problem is I do not see where to build the ViewPager in my current code...

How do organize an app using fragments?

I am currently re-coding most of the back end of my android app in order to follow the design guidelines more closely. Currently I am using all activities and zero fragments. I am trying to switch to fragments in order to use the slide out navigation draw and eventually some sliding tabs.
For navigation right now I have this drop down menu which when an item is clicked launches a new activity:
The "Your Statistics" activity is kind of like the home page, where the user will enter the app too. I also want the user to be able to get back to that "page" from anywhere in the app.
My activity that I plan to run the draw from I have a draw layout called fragment_main:
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<FrameLayout
android:id="#+id/main"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</FrameLayout>
<ListView
android:id="#+id/drawer"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#FFF"
android:choiceMode="singleChoice"/>
</android.support.v4.widget.DrawerLayout>
and my activity which loads the drawer layout is:
public class MainDraw extends FragmentActivity {
final String[] data ={"one","two","three"};
final String[] fragments ={
"com.beerportfolio.beerportfoliopro.FragmentOne",
"com.beerportfolio.beerportfoliopro.FragmentTwo",
"com.beerportfolio.beerportfoliopro.FragmentThree"};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
//todo: load statistics
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActionBar().getThemedContext(), android.R.layout.simple_list_item_1, data);
final DrawerLayout drawer = (DrawerLayout)findViewById(R.id.drawer_layout);
final ListView navList = (ListView) findViewById(R.id.drawer);
navList.setAdapter(adapter);
navList.setOnItemClickListener(new AdapterView.OnItemClickListener(){
#Override
public void onItemClick(AdapterView<?> parent, View view, final int pos,long id){
drawer.setDrawerListener( new DrawerLayout.SimpleDrawerListener(){
#Override
public void onDrawerClosed(View drawerView){
super.onDrawerClosed(drawerView);
FragmentTransaction tx = getSupportFragmentManager().beginTransaction();
tx.replace(R.id.main, Fragment.instantiate(MainDraw.this, fragments[pos]));
tx.commit();
}
});
drawer.closeDrawer(navList);
}
});
FragmentTransaction tx = getSupportFragmentManager().beginTransaction();
tx.replace(R.id.main,Fragment.instantiate(MainDraw.this, fragments[0]));
tx.commit();
}
}
IN my //todo: comment I should load my first "home" fragment there which is my statistics "page" ? And then all the other fragments will be transitioned in and out based on the draw clicks?
Thanks for your help in advance, I want to make sure I am doing this right, I used to code just to get things working which is why I am now re doing a huge chunk of my code. Please share any other fragment tips to that I might need!

First of all read the well written documentation, it answers to your doubts.
I would share my personal pattern to convert existing Activity to Fragment
Create your on abstract Fragment class from which derive all drawer fragments, this can help to group common attributes
Use a method like selectItem() on docs, it helps to explicit do a call at first run (showing the "home" fragment) and then from onItemClick
move inflating XML layout from Activity.onCreate() code to Fragment.onCreateView() (ie setContentView to inflater.inflate(R.layout.my_layout, container, false), in many cases you can copy all code from onCreate() to onCreateView
move initialization code from Activity.onCreate() to Fragment.onActivityCreated(), this is very useful when both Activity (including fragment) and the direct Fragment exist, for example if your app exposes a "Share with" action you continue to have the Activity that inside the XML includes a <fragment/> and the fragment can be created from the drawer, too
if you need to communicate from Activity to Fragment and viceversa I suggest to create an interface and store it inside the 'onAttach()' (see google example)
Action bar items must be hidden when drawer is open, again take a look at example used in doc, here is very useful the interface to communicate from activity to fragment, the main activity can tell if drawer is open and the fragment can call the interface
public interface FragmentActivityStatus {
public boolean isDrawerOpen();
}
The activity
public class MainActivity extends Activity implements FragmentActivityStatus {
#Override
public boolean isDrawerOpen() {
return drawerLayout.isDrawerOpen(drawerList);
}
}
The fragment
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
fragmentActivityStatus = (FragmentActivityStatus)activity;
}
#Override
public void onPrepareOptionsMenu(Menu menu) {
boolean isMenuVisible = !fragmentActivityStatus.isDrawerOpen();
menu.findItem(R.id.my_menu).setVisible(isMenuVisible);
super.onPrepareOptionsMenu(menu);
}
Not related to fragment, in your code you declare class names as string, consider to create a Class array if you refactor packages the code continue to work, then you can call the Class.getName() to obtain the string to pass to Fragment.instantiate()
final Class<?>[] fragments = {
FragmentOne.class,
FragmentTwo.class,
FragmentThree.class};
Then
FragmentTransaction tx = getSupportFragmentManager().beginTransaction();
tx.replace(R.id.main, Fragment.instantiate(MainDraw.this,
fragments[pos].getName()));
tx.commit();

No view found for ID xxx for fragment (nested fragments)

I have an activity that has a ViewPager in the layout.
I have two fragments which display, one for each tab.
One of the fragments is designed to host other fragments - this is the CustomerMainFragment which inflates fragment_customer_main:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/lyt_customer_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<FrameLayout
android:id="#+id/fragment_customer_content"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</LinearLayout>
This then adds CustomerSearchFragment to the FrameLayout which inflates fragment_customer_search.
CustomerSearchFragment also has the following override to switch out the search fragment for a detail fragment on a button press:
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
Button btnSearch1 = (Button) view.findViewById(R.id.button1);
if (btnSearch1 != null) {
btnSearch1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// This is important bit
Fragment customerDetailFragment = new CustomerDetailFragment();
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
transaction.addToBackStack(null);
transaction.replace(R.id.fragment_customer_content, customerDetailFragment).commit();
}
});
}
}
After clicking the button I get the following error:
java.lang.IllegalArgumentException: No view found for id 0x7f080006
(com.chrisbeckyapps.sample:id/fragment_customer_content) for fragment
CustomerDetailFragment{4280b0b8 #0 id=0x7f080006}
I'm new to fragments and understand the concepts, but I'm stumped by this. I originally had the search fragment going straight into the pager, but then replacing it with the detail fragment mean it just showed over the top, and my research led to this being a better solution.
I have wondered about trying to move the search logic to the CustomerMainFragment but this means hooking up a lot of logic and I thought you could embed logic within fragments.
Suggestions?

Sorry, just found such a simple fix.
In my onclick handler, I just had to change from getChildFragmentManager to getFragmentManager