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How to show fragment only when button pressed?

I'm trying to show an image below a button only after the button has been pressed. My problem is that the fragment is shown immediately when the app is started and not only after the button has been pressed.
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void say_hello(View view){
Fragment fragment = new ExampleFragment();
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.fragment2, fragment).commit();
}
}
public class ExampleFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.news_articles, container, false);
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:orientation="vertical"
android:layout_height="fill_parent"
tools:context=".MainActivity">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal|center_vertical"
android:text="PRESS THIS"
android:id = "#+id/test_button"
android:background="#drawable/test_button"
android:onClick="say_hello"
/>
<fragment
android:id="#+id/fragment2"
android:name="com.example.tic_tac_toe.ExampleFragment"
android:layout_width="match_parent"
android:layout_height="643dp" />
</LinearLayout>
<ImageView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/cool_dog">
</ImageView>
I'm guessing the fragment shows up when the app is started because of the name I give to the fragment in the XML, but the fragment needs a name otherwise I only get error. How do I get the fragment to display nothing before I have clicked the button?

Instead of using <fragment /> view in your xml, you can use Framelayout and add your fragment to this Framelayout on button click using the following code -
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.add(R.id.mainframe, fragment);
transaction.commit();
Where mainframe is the id of Framelayout.

You can try doing this
android.app.Fragment fragment = getActivity().getFragmentManager().findFragmentByTag("YOUR_FRAGMENT_TAG");
getActivity().getFragmentManager().beginTransaction().hide(fragment);
inside your click event.

Replace one fragment with an another fragment

I want to replace an old Fragment with a new Fragment, but i still get the buttons of the old Fragment that is still visible in the new fragment.
In the old one, on a button click
FragmentTransaction transaction = getFragmentManager().beginTransaction();
Fragment newFragment = GenericMood.newInstance("a","b");
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack if needed
transaction.replace(R.id.allmoods, newFragment);
transaction.addToBackStack(null);
transaction.commitAllowingStateLoss();
I can replace the old Fragment with the new one, but the buttons from R.id.allmoods Fragment still visible on top of the new Fragment.
I tried with this given below code.
FragmentTransaction transaction = getFragmentManager().beginTransaction();
Fragment newFragment = GenericMood.newInstance("a","b");
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack if needed
transaction.replace(((ViewGroup)getView().getParent()).getId(), newFragment);
transaction.addToBackStack(null);
transaction.commitAllowingStateLoss();
XML files:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/allmoods"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorPrimary"
tools:context="com.moodoff.Moods">
<Button
android:text="Button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="64dp"
android:id="#+id/btn_btn"
android:height="80dp"
android:width="100dp"
android:onClick="putmeoff"
android:layout_marginLeft="17dp"
android:layout_marginStart="17dp"/>
</RelativeLayout>
This is the fragment that is supposed to replace the above:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:id="#+id/genericmood"
android:layout_height="match_parent"
android:background="#color/colorPrimary"
tools:context="com.moodoff.GenericMood">
<!-- TODO: Update blank fragment layout -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#000000"
android:layout_gravity="fill_horizontal"
android:id="#+id/floatingButtons"
>
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="1dp"
android:layout_marginRight="14dp"
app:backgroundTint="#ffffff"
android:layout_alignParentTop="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:src="#drawable/cameraicon"
android:id="#+id/btn_camera"
app:fabSize="mini"
/>
</RelativeLayout>
</FrameLayout>
Both doesn't work. What to do?
UPDATE: After replacing with the proper container the buttons had gone but the new fragment is not getting instantiated properly. I gets a pure blank white screen.
my activity_alltabs.xml looks like this:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.moodoff.AllTabs">
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#android:color/background_dark" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>

I Have worked on fragments before and hope this would help you out and give you a better understanding of the flow. Firstly, your MainActivity.xml file will look like this :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.example.activity.HomeActivity">
//This frameLayout will contain all your fragments view.
<FrameLayout
android:id="#+id/container_view"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
</RelativeLayout>
Next, you create two fragments and their XML is mentioned below :
fragment1.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clickable="true" // important to have this
tools:context=".fragments.frament1">
<Button
android:id="#+id/btn"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"/>
</RelativeLayout>
The next fragment would look exactly the same as mentioned above. Here is the Fragment1.class:
public class Fragment1 extends Fragment implements View.OnClickListener {
Button btn;
public Fragment1() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment1, container, false);
view.setBackgroundColor(Color.WHITE);
//Perform required conditions and return view
button = (Button) view.findViewById(R.id.btn);
button.setOnClickListener(this);
return view;
}
public void onClick(View v) {
switch(v.getId())
{
case R.id.btn:
//replace current fragment on button click
Fragment fragment2= new Fragment2();
getFragmentManager().beginTransaction().
replace(R.id.container_view, fragment2).
addToBackStack("frags").commit();
break;
}
}
}
And the Fragment2 would be as follows :
public class Fragment2 extends Fragment{
String TAG = "Fragment2";
public Fragment2() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment2,container,false);
view.setBackgroundColor(Color.WHITE);
return view;
}
}
As I mentioned earlier, the xml file would be the same as fragment1.xml. What is more important here is that the main activity will contain a layout which will take the fragments view when ever the user switches fragments. Hence we use the replace method which would just replace the previous view with the fragments view specified by us.

To understand the flow of fragment transition, first of all, you have to know about its structure in activity.
Let's see:
a) Activity: At bottom of everything (MainActivity)
activity_main.xml :-
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>
Here #+id/container is the layout over we do transitions of fragment contents.
B) FragmentA : Initially added fragment to the container of MainActivity.
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
//Instance of fragment
Fragment newFragment = FragmentA.newInstance("a","b");
//It will replace the fragment content view to container of main activity
ft.replace(R.id.container, newFragment);
//FragmentA is added to back stack with it's name as a tag
ft.addToBackStack(FragmentA.class.getSimpleName());
ft.commitAllowingStateLoss();
B) FragmentB : Replace FragmentA with FragmentB
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
//Instance of fragment
Fragment newFragment = FragmentB.newInstance("a","b");
//It will replace the fragment content view to container of fragment A which // is previously replaced to main activity container
ft.replace(R.id.container, newFragment);
//FragmentB is added to back stack with it's name as a tag
ft.addToBackStack(FragmentB.class.getSimpleName());
ft.commitAllowingStateLoss();
So main thing behind this is to replace/add fragment content view to the activity container view.

In your Activity's onCreate function, you should be calling setContentView(R.layout.main), then when you want to load a Fragment, you choose a ViewParent within R.layout.main. The fragment will become the child of that ViewParent. So the id passed into FragmentTransaction.replace, is the id of the ViewParent in R.layout.main.
It makes sense that the Button in your allmoods RelativeLayout would remain because the FragmentTransaction.replace function only replaces an existing fragment that is in that container. Everything in R.layout.main will remain. This is how an Activity keeps static content, like drawers or toolbars.
When you load your "new fragment" you will use the same id. So the "new fragment" replaces the "old fragment" as the new child of the ViewParent within R.layout.main.
Here is the Fragments API guide.
Update:
When you call FragmentTransaction.replace in your Activity's onCreate function, this could be recreating an existing Fragment. Make sure the savedInstanceState (the Bundle passed into onCreate) is null. If the savedInstanceState is not null, then the fragment probably already exists and you can find it like this;
Fragment f = getFragmentManager().findFragmentByTag(YOUR_FRAGMENT_TAG);
Update 2:
Here is a guide that should help you. It looks like you could use FragmentPagerAdapter to simplify your fragment transactions.

try this once,
1. if you are passing any value upon button click
In Activity
Category category=new Category();
Bundle bundle=new Bundle();
bundle.putString("heading",heading);
bundle.putInt("position",position1+1);
bundle.putString("url",url);
bundle.putString("sku",sku);
bundle.putBoolean("flag",flag);
category.setArguments(bundle);
FragmentManager fragmentManager = getSupportFragmentManager();
final FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.fragmentCategories,category);
fragmentTransaction.commit();
In fragment
Bundle bundle=getArguments();
if(getArguments()!=null) {
position = bundle.getInt("position");
heading = bundle.getString("heading");
url = bundle.getString("url");
sku=bundle.getString("sku");
flag=bundle.getBoolean("flag");
tvHeading.setText(heading);
video_chapter = handler.getContent_Aspects(position);
adapter = new Chapter_content_Adapter(getActivity(), video_chapter, url, heading, position);
gvChapter.setAdapter(adapter);
}
2.if simply calling fragment
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentCategories=fragmentManager.findFragmentById(R.id.fragmentCategories);
fragmentTransaction.commit();

Try the following code.
A) Create Activity as follows :
MainActivity
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity implements ShowNextFragment{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentA fragmentA=new FragmentA();
FragmentTransaction fragmentTransaction=getFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.container,fragmentA);
fragmentTransaction.addToBackStack("A");
fragmentTransaction.commitAllowingStateLoss();
}
#Override
public void showFragment() {
FragmentB fragmentB=new FragmentB();
FragmentTransaction fragmentTransaction=getFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.container,fragmentB);
fragmentTransaction.addToBackStack("B");
fragmentTransaction.commitAllowingStateLoss();
}
}
B) Create 2 fragments as follows :
Fragment A
import android.app.Fragment;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class FragmentA extends Fragment {
private ShowNextFragment showNextFragment;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
try {
showNextFragment=(ShowNextFragment)getActivity();
Log.e("CAllback","Set");
}catch (ClassCastException e){
Log.e("Error","Please Implement ShowFragment Interface");
}
return inflater.inflate(R.layout.fragment_a,container,false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
view.findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (showNextFragment!=null){
showNextFragment.showFragment();
}
}
});
}
}
Fragment B
import android.app.Fragment;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class FragmentB extends Fragment {
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_b,container,false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
C) Create an interface as follows
public interface ShowNextFragment {
void showFragment();
}
D) create following xmls as :
i) activity_main
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
</RelativeLayout>
ii) fragment_a
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorcyan"
android:orientation="vertical">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Show Fragment B" />
</LinearLayout>
iii) fragment_b
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorgreen"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Fragment B"
android:layout_centerVertical="true"
android:layout_alignRight="#+id/btn_camera"
android:layout_alignEnd="#+id/btn_camera" />
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:backgroundTint="#ffffff"
android:src="#android:drawable/ic_dialog_email"
android:id="#+id/btn_camera"
app:fabSize="mini"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>

The problem was the the container ID that was passing to the replace method was the ID of the fragment that was replacing, not the ID of the fragment container. This seems to explain why some of the original fragment controls were remaining after the replace - that entire fragment wasn't being replaced.
Please change it to get the fragment container view ID, and it will work! Here's the code:
transaction.replace(((ViewGroup)(getView().getParent())).getId(), fragment);
I found the answer for getting the container view ID of a fragment here, Get fragment's container view id.

Just make buttons setVisibility(View.GONE) in your activity when that fragment is begin transaction.

put your next fragment UI elements in Card View. define a LinearLayout or other view groups as root and inside this root create a Card view and put your other elements in Card View . when you inflate it in Card View then the hole of new fragment inflate on the previous fragment.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parenter code hereent"
android:layout_height="match_parent"
android:orientation="vertical">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginBottom="-20dp"
app:cardCornerRadius="20dp">
......... your UI Elements .......
//, for example, define other LinearLayout inside the Card View
and put other elements inside it like TextView, Button and
so on...
</androidx.cardview.widget.CardView>
</LinearLayout>

IllegalArgumentException:No view found for id

I get the following exception:
java.lang.IllegalArgumentException:
No view found for id 0x7f04001a (com.whatever:layout/fragment_main)
Looking at similar questions on SO:
One answer suggests using getChildFragmentManager() instead of getSupportFragmentManager().
This is not an option since MainActivity is not a Fragment.
Another answer suggests that fragment_main is not a child of activity_main, but I think I have that setup in activity_main.xml with tools:layout="#layout/fragment_main
Another suggests that setContent() has not been called, but I have that in onCreate()
What am I missing?
MainActivity.java
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public void onStart() {
super.onStart();
// create fragment immediately
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.add(R.layout.fragment_main, new MainActivityFragment());
fragmentTransaction.commit();
boolean wereThereWereAnyPendingTransactions = fragmentManager.executePendingTransactions();
}
}
MainActivityFragment.java
public class MainActivityFragment extends Fragment implements Observer<String> {
public MainActivityFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_main, container, false);
}
activity_main.xml
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/fragment"
android:name="com.whatever.MainActivityFragment"
tools:layout="#layout/fragment_main"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
fragment_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/fragment_main_table"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
tools:context=".MainActivityFragment">
<TextView
android:text="#string/fragment_main_xml"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</RelativeLayout>
The answer with respect to code:
actvity_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_frame_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
tools:context=".MainActivity" >
</FrameLayout>
MainActivity.java:
...
fragmentTransaction.add(R.id.activity_frame_layout, new MainActivityFragment());
...

If you embed a Fragment inside of an Activity XML layout, you do not create it dynamically. The system does it for you. So there is no need to create the transaction and commit it, the Fragment will be created and added when you called setContentView().
Note that the tools:layout= line does not do anything at runtime. It is strictly for the tools to better link layouts and components together.

Fragments inside a fragment Android application

I'm trying to put 2 fragments inside a fragment. I found some code on internet but, as far as I could go, I don't succeed to put 2 fragments in 1 fragment.
I have seen tips dealing with FragmentManager and especially the method getChildFragmentManager() but I don't know how it works with 2 fragments.
For the story, I'm using an activity with ActionBar which creates 3 fragments. In one of them, I need to handle a graph and a kind of menu to change the graph scale. In this way, I need 2 fragments in one fragment.
Here is the code :
The fragment which handles the others:
public class GraphDisplayFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View myFragmentView = inflater.inflate(R.layout.graph_fragment, container, false);
return myFragmentView;
}
}
The code to draw the graph:
public class GraphFragment extends Fragment {
private static final int SERIES_NR = 1;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
GraphicalView myFragmentView = ChartFactory.getTimeChartView(this.getActivity(), getDateDemoDataset(), getDemoRenderer(),null);
return myFragmentView;
}
//some functions to set graph propreties
}
The XML files :
graph_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<fragment
android:id="#+id/graph_fragment"
android:name="com.test.GraphFragment"
android:layout_width="match_parent"
android:layout_height="259dp" >
</fragment>
<fragment
android:name="com.test.GraphDetailFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/graph_detail_fragment">
</fragment>
</LinearLayout>
graph_detail.xml with a test implementation
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="211dp"
android:layout_height="wrap_content"
android:text="TextView" />
</LinearLayout>
The weird thing is, it works at the begining when I switch between fragments in the ActionBar but after 3-4 moves, I get this error :
android.view.InflateException: Binary XML file line #7: Error inflating class fragment
If anyone has the solution, it would be awesome!

So first off change your xml for graph_fragment.xml to this
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<FrameLayout
android:id="#+id/graph_fragment_holder"
android:layout_width="match_parent"
android:layout_height="259dp" >
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/graph_detail_fragment_holder">
</FrameLayout>
</LinearLayout>
Then in code to inflate them from the fragment use something like this
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.graph_fragment,
container, false);
FirstChildFragment frag1 = (FirstChildFragment) getChildFragmentManager()
.findFragmentById(R.id.first_frag_layout);
SecondChildFragment frag1 = (SecondChildFragment) getChildFragmentManager()
.findFragmentById(R.id.second_frag_layout);
if (null == frag1) {
FirstChildFragment = new frag1();
FragmentTransaction transaction = getChildFragmentManager()
.beginTransaction();
transaction.add(R.id.graph_fragment_holder, frag1)
.addToBackStack(null).commit();
}
if (null == frag2) {
SecondChildFragment = new frag2();
FragmentTransaction transaction = getChildFragmentManager()
.beginTransaction();
transaction.add(R.id.graph_detail_fragment_holder, frag2)
.addToBackStack(null).commit();
}
return rootView;
}

MyFragment myFragment = (MyFragment)getChildFragmentManager().findFragmentById(R.id.my_fragment);

You can try to use the method *findFragmentById(fragment_id)* from SupportFragmentManager to get the instance of fragment from your .xml file and insert your fragment there.
Something like:
Fragment myFragment = getSupportFragmentManager().findFragmentById(R.id.myFragmentId);
I hope to help you.
Best regards.
Adriano

How to create multiple fragments programmatically?

I am trying to show multiple fragments on the one screen by creating them programmatically. I am able to do this no problem by including each fragment into the activities layout file. However when I try and do it programmatically Im confused.This is what I have so far for two fragments on a screen.
Main Class:
public class MainActivity extends FragmentActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentOne one = new FragmentOne();
FragmentTwo two = new FragmentTwo();
FragmentThree three = new FragmentThree();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.add(R.id.imOne, one, "fragmentone");
ft.add(R.id.imTwo, two, "fragmenttwo");
ft.add(R.id.imThree, three, "fragmenthree");
ft.commit();
}
}
Fragment One:
public class FragmentOne extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view = inflater.inflate(R.layout.frag_one, container, false);
return view;
}
}
Fragment Two:
public class FragmentTwo extends Fragment{
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view = inflater.inflate(R.layout.frag_two, container, false);
return view;
}
}
The layout files for my two fragment classes just contain a simple TextView.
And then the activity_main.xml layout file for my main class:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<FrameLayout
android:id="#+id/imOne"
android:name="com.david.twofragexample.FragmentOne"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="2" />
<FrameLayout
android:id="#+id/imTwo"
android:name="com.david.twofragexample.FragmentTwo"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="2" />
<FrameLayout
android:id="#+id/imThree"
android:name="com.david.twofragexample.FragmentThree"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="2" />
</LinearLayout>
When I try and do it programatically I get confused as to what should be in my activity_main.xml file. So from the Android Developer Guide(http://developer.android.com/guide/components/fragments.html) it says to use
FragmentManager fragmentManager = getFragmentManager()
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
FragmentOne fragment = new FragmentOne();
fragmentTransaction.add(R.id.fragment_container, fragment);
fragmentTransaction.commit();
So when I add this code to my onCreate method what changes do I have to make to my activity_main.xml file to do this programmatically?I don't see where R.id.fragment_container comes from. How can I determine where on the screen my new fragment will go?Thanks
EDIT: I am developing this on a tablet and not a phone.This has now been solved and the above code will add three fragments programmatically.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<FrameLayout
android:id="#+id/list"
android:name="com.david.twofragexample.FragmentOne"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="2" />
<FrameLayout
android:id="#+id/viewer"
android:name="com.david.twofragexample.FragmentTwo"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="2" />
</LinearLayout>
In your Activity:
FragmentOne one = new FragmentOne();
FragmentTwo two = new FragmentTwo();
fm = getSupportFragmentManager();
fm.beginTransaction().replace(R.id.list, one, "fragmentone").commit();
fm.beginTransaction().replace(R.id.viewer, two, "fragmenttwo").commit();
I suggest you study this:
http://developer.android.com/reference/android/app/Fragment.html
and fully understand the fragment lifecycle, etc. The way I show is quick and dirty, but not neccesarilly best.

As I don't have higher enough reps to comment yet, I will just leave the information here -- the way Rafael T suggested does work nicely, although I also had my doubt at the first place.
1) Define your xml like this:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
>
2) Add each fragment into the same slot:
View box = v.findViewById(R.id.container);
FragmentTransaction ft = getFragmentManager().beginTransaction();
for (String catalog : mCatalogs) {
Fragment fragment = HighlightedProductFragment.newInstance(catalog);
ft.add(R.id.container, fragment, catalog);
}
ft.commit();
Thanks for the solution for this tricky requirement.

Try it like this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
as your activity_main.xml
You asked yourself the right question: where is the id fragment_container, and the answer was: nowhere. >ou also set your layout to horizontal, which makes it very likely, that added Views will be kind of 'out of screen'