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Why do I get the android.view.InflateException when using FragmentContainerView

I am still pretty new to fragments and I am sure I do not understand things correctly. But I hope I can learn from this now.
I follow this guide for connecting my xml with the fragments: https://developer.android.com/guide/fragments/create. But when starting the app I get an error that says that some parts are not compatible.
Here are my files:
main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.fragment.app.FragmentContainerView
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"
tools:context=".MainActivity"
android:id="#+id/main"
android:orientation="horizontal"
>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="30dp">
<TextView
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:text="#string/brand"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/item"
android:textAppearance="#style/TextAppearance.AppCompat.Headline"
android:textStyle="bold"
/>
<ImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
app:srcCompat="#drawable/gibson_1"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/price"
android:gravity="right"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:gravity="right"
>
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="phone"
android:layout_marginRight="15dp"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add to cart"
android:drawableLeft="#drawable/drawablestart"
android:id="#+id/addCart"
/>
</LinearLayout>
</FrameLayout>
</androidx.fragment.app.FragmentContainerView>
MainActive.java
package at.hlpinkafeld.android.musicstore;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.os.Bundle;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
public MainActivity() {
super(R.layout.activity_main);
}
#Nullable
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.setReorderingAllowed(true)
.add(R.id.main, ProductDetailFragment.class, null)
.commit();
}
}
}
fragment.java
package at.hlpinkafeld.android.musicstore;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import com.google.android.material.textview.MaterialTextView;
public class ProductDetailFragment extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view =inflater.inflate(R.layout.activity_main,container,false);
System.out.println(view);
return view;
}
}
the error
E/AndroidRuntime: FATAL EXCEPTION: main
Process: at.hlpinkafeld.android.musicstore, PID: 13020
java.lang.RuntimeException: Unable to start activity ComponentInfo{at.hlpinkafeld.android.musicstore/at.hlpinkafeld.android.musicstore.MainActivity}: android.view.InflateException: Binary XML file line #11 in at.hlpinkafeld.android.musicstore:layout/activity_main: Views added to a FragmentContainerView must be associated with a Fragment. View android.widget.FrameLayout{58ede95 V.E...... ......I. 0,0-0,0} is not associated with a Fragment.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3635)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7839)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
Caused by: android.view.InflateException: Binary XML file line #11 in at.hlpinkafeld.android.musicstore:layout/activity_main: Views added to a FragmentContainerView must be associated with a Fragment. View android.widget.FrameLayout{58ede95 V.E...... ......I. 0,0-0,0} is not associated with a Fragment.
Caused by: java.lang.IllegalStateException: Views added to a FragmentContainerView must be associated with a Fragment. View android.widget.FrameLayout{58ede95 V.E...... ......I. 0,0-0,0} is not associated with a Fragment.
at androidx.fragment.app.FragmentContainerView.addView(FragmentContainerView.kt:266)
at android.view.ViewGroup.addView(ViewGroup.java:5048)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1131)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1088)
at android.view.LayoutInflater.inflate(LayoutInflater.java:686)
at android.view.LayoutInflater.inflate(LayoutInflater.java:538)
at android.view.LayoutInflater.inflate(LayoutInflater.java:485)
at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:710)
at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:195)
at androidx.activity.ComponentActivity.onCreate(ComponentActivity.java:356)
at androidx.fragment.app.FragmentActivity.onCreate(FragmentActivity.java:217)
at at.hlpinkafeld.android.musicstore.MainActivity.onCreate(MainActivity.java:25)
at android.app.Activity.performCreate(Activity.java:8051)
at android.app.Activity.performCreate(Activity.java:8031)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1329)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3608)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7839)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
For help and an explanation why it didn't work like that, would be nice

I think you might want to try loading a simple fragment into an activity.
Try this code. It's working for you.
For more info: click
Note: Always create a new object like this to load fragments new ProductDetailFragment() , and use setContentView(); inside of onCreate().
1. First of all, create the perfect activity to load a fragment.
MainActivity.class
public class MainActivity extends AppCompatActivity {
String TAG = "MainActivity";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportFragmentManager().beginTransaction()
.setReorderingAllowed(true)
.add(R.id.main, new ProductDetailFragment(), null)
.commit();
}
}
activity_main.xml
<?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"
tools:context=".MainActivity"
android:id="#+id/main"
android:orientation="horizontal"
>
</RelativeLayout>
2. create fragment ProductDetailFragment.class
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
public class ProductDetailFragment extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view =inflater.inflate(R.layout.fragment_product_details,container,false);
System.out.println(view);
return view;
}
}
3. make diffrent layout for fragment fragment_product_details.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:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="30dp">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/brand" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/item"
android:textAppearance="#style/TextAppearance.AppCompat.Headline"
android:textStyle="bold" />
<ImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
app:srcCompat="#drawable/gibson_1" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="right"
android:text="#string/price" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="right"
android:orientation="horizontal">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="15dp"
android:inputType="phone" />
<Button
android:id="#+id/addCart"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/drawablestart"
android:text="Add to cart" />
</LinearLayout>
</FrameLayout>

You misunderstood the actual code in the link :- https://developer.android.com/guide/fragments/create
You put the fragment xml code inside your fragment container view which is inside your main activity.
You just need to declare the fragment container view defined below.
The fragment container view is main container which contains your fragment like below in your main activity.
<androidx.fragment.app.FragmentContainerView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fragment_container_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:name="<provide your fragment class here from your code it is ProductDetailFragment>" />
Then create the fragment xml file in layout directory named fragment_product_detail:-
Then put your fragment xml code in it. like below.
fragment_product_detail.xml :-
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="30dp">
<TextView
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:text="#string/brand"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/item"
android:textAppearance="#style/TextAppearance.AppCompat.Headline"
android:textStyle="bold"
/>
<ImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
app:srcCompat="#drawable/gibson_1"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/price"
android:gravity="right"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:gravity="right"
>
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="phone"
android:layout_marginRight="15dp"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add to cart"
android:drawableLeft="#drawable/drawablestart"
android:id="#+id/addCart"
/>
</LinearLayout>
</FrameLayout>
Then in your fragment onCreateView method make sure to inflate the fragment layout like below :-
View view =inflater.inflate(R.layout.fragment_product_detail,container,false);
This will resolve your problem.
Let me know if you still face any issue.

Accessing Parent Activity Button in Fragment Crashes App

Hey guys I am a beginner in Android Develpoment. I am currently learning Navigation Components, but stuck in this app. I am setting listener to the button present in the activity_main.xml inside the FirstFragment.java and SecondFragment.java but my app crashes. I don't know what I am doing wrong.
Main Activity.java
package com.ahstore.inventory;
import android.os.Bundle;
import com.google.android.material.snackbar.Snackbar;
import androidx.appcompat.app.AppCompatActivity;
import android.view.View;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.fragment.NavHostFragment;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;
import com.ahstore.inventory.databinding.ActivityMainBinding;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
private AppBarConfiguration appBarConfiguration;
private ActivityMainBinding binding;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = ActivityMainBinding.inflate(getLayoutInflater());
setContentView(binding.getRoot());
setSupportActionBar(binding.toolbar);
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_main);
appBarConfiguration = new AppBarConfiguration.Builder(navController.getGraph()).build();
NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);
binding.fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_main);
return NavigationUI.navigateUp(navController, appBarConfiguration)
|| super.onSupportNavigateUp();
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:theme="#style/Theme.Inventory.AppBarOverlay"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?attr/colorPrimary"
app:popupTheme="#style/Theme.Inventory.PopupOverlay" />
</com.google.android.material.appbar.AppBarLayout>
<HorizontalScrollView
android:id="#+id/horizontalScrollView"
android:layout_width="409dp"
android:layout_height="50dp"
android:layout_marginStart="10dp"
android:layout_marginEnd="10dp"
android:scrollIndicators="none"
android:scrollbarAlwaysDrawHorizontalTrack="false"
android:scrollbarAlwaysDrawVerticalTrack="false"
android:scrollbars="none"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/appBarLayout">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="5dp"
android:layout_weight="1"
android:text="Button" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="5dp"
android:layout_weight="1"
android:text="Button" />
</LinearLayout>
</HorizontalScrollView>
<fragment
android:id="#+id/nav_host_fragment_content_main"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:defaultNavHost="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.5"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/horizontalScrollView"
app:navGraph="#navigation/nav_graph" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginBottom="16dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:srcCompat="#android:drawable/ic_input_add"
tools:ignore="SpeakableTextPresentCheck,SpeakableTextPresentCheck" />
</androidx.constraintlayout.widget.ConstraintLayout>
FirstFragment.java
package com.ahstore.inventory;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import androidx.navigation.fragment.NavHostFragment;
import com.ahstore.inventory.databinding.FragmentFirstBinding;
public class FirstFragment extends Fragment {
private FragmentFirstBinding binding;
#Override
public View onCreateView(
LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState
) {
View view=inflater.inflate(R.layout.fragment_first,container,false);
return view;
}
public void onViewCreated(#NonNull View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
Button button1=view.findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
NavHostFragment.findNavController(FirstFragment.this)
.navigate(R.id.action_FirstFragment_to_SecondFragment);
}
});
}
#Override
public void onDestroyView() {
super.onDestroyView();
binding = null;
}
}
fragment_first.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
tools:context=".FirstFragment">
<ScrollView
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/textView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="First" />
</LinearLayout>
</ScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>
SecondFragment.java
package com.ahstore.inventory;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import androidx.navigation.fragment.NavHostFragment;
import com.ahstore.inventory.databinding.FragmentSecondBinding;
public class SecondFragment extends Fragment {
private FragmentSecondBinding binding;
#Override
public View onCreateView(
LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState
) {
View view=inflater.inflate(R.layout.fragment_second,container,false);
return view;
}
public void onViewCreated(#NonNull View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
Button button=view.findViewById(R.id.button2);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
NavHostFragment.findNavController(SecondFragment.this)
.navigate(R.id.action_SecondFragment_to_FirstFragment);
}
});
}
#Override
public void onDestroyView() {
super.onDestroyView();
binding = null;
}
}
fragment_second.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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/cl"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".SecondFragment">
<TextView
android:id="#+id/textview_second"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="am second"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Error
2022-03-04 16:54:11.473 2392-2392/com.ahstore.inventory E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.ahstore.inventory, PID: 2392
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.ahstore.inventory/com.ahstore.inventory.MainActivity}: android.view.InflateException: Binary XML file line #79 in com.ahstore.inventory:layout/activity_main: Binary XML file line #79 in com.ahstore.inventory:layout/activity_main: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3800)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3976)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2315)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:246)
at android.app.ActivityThread.main(ActivityThread.java:8550)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130)
Caused by: android.view.InflateException: Binary XML file line #79 in com.ahstore.inventory:layout/activity_main: Binary XML file line #79 in com.ahstore.inventory:layout/activity_main: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #79 in com.ahstore.inventory:layout/activity_main: Error inflating class fragment
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.ahstore.inventory.FirstFragment.onViewCreated(FirstFragment.java:35)
at androidx.fragment.app.Fragment.performViewCreated(Fragment.java:2987)
at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:546)
at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:282)
at androidx.fragment.app.FragmentStore.moveToExpectedState(FragmentStore.java:112)
at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1647)
at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:3128)
at androidx.fragment.app.FragmentManager.dispatchViewCreated(FragmentManager.java:3065)
at androidx.fragment.app.Fragment.performViewCreated(Fragment.java:2988)
at androidx.fragment.app.FragmentStateManager.ensureInflatedView(FragmentStateManager.java:392)
at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:281)
at androidx.fragment.app.FragmentLayoutInflaterFactory.onCreateView(FragmentLayoutInflaterFactory.java:140)
at androidx.fragment.app.FragmentController.onCreateView(FragmentController.java:135)
at androidx.fragment.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:319)
at androidx.fragment.app.FragmentActivity.onCreateView(FragmentActivity.java:298)
at android.view.LayoutInflater.tryCreateView(LayoutInflater.java:1067)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:995)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:959)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1121)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1082)
at android.view.LayoutInflater.inflate(LayoutInflater.java:680)
at android.view.LayoutInflater.inflate(LayoutInflater.java:532)
at com.ahstore.inventory.databinding.ActivityMainBinding.inflate(ActivityMainBinding.java:75)
at com.ahstore.inventory.databinding.ActivityMainBinding.inflate(ActivityMainBinding.java:69)
at com.ahstore.inventory.MainActivity.onCreate(MainActivity.java:32)
at android.app.Activity.performCreate(Activity.java:8198)
2022-03-04 16:54:11.474 2392-2392/com.ahstore.inventory E/AndroidRuntime: at android.app.Activity.performCreate(Activity.java:8182)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3773)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3976)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2315)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:246)
at android.app.ActivityThread.main(ActivityThread.java:8550)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130)

Here are a few points that will help you understand your issue better
Your activity and fragments have their own respective layout files (xmls)
View are bound within their layout files. Simply put, if an element with id, say A, is present in activity_main.xml, then it can only be accessed when the layout being inflated is activity_main.xml. If the contentView of your Activity is activity_main.xml, it will be able to access all Views inside the layout file.
In fragments, the layout is inflated in the onCreateView method, which returns the resulting View for the Fragment. The findViewById(id) method is called against that View object. The method will look for the View with the given id inside that View only. If it is able to find the View it will return it, else it will return null. Same goes for finding a View inside an Activity (you do not need to specify the View for an Activity as it will automatically reference the layout that is specified in setContentView).
Now that we have the above points cleared, we can see the issue that you are facing. Firstly, the buttons with ids button1 and button2 are in your activity_main.xml layout file. However you are trying to access these from your Fragment1 and Fragment2 classes. But your Fragment1 and Fragment2 classes have their own layout files which do not have the two buttons. So, when you try to retrieve the buttons (using findViewById), it returns null because the buttons are not present in the layout. You then try to set a click listener. Since, the button object is null, calling any method on it will result in a Null Pointer Exception being throw.
We now understand what you are doing wrong. Now, how do we fix this. First you need to understand what it is you want to achieve. In this case I would suggest that you move both buttons to the respective Fragment layouts i.e. the View with id button1 will go to Fragment1 and the View with id button2 will go to Fragment2. This should help resolve the NPE that you are facing.
Still there are some cases where a Fragment might want to access a View that is present in its parent Activity. One of the ways to do this would be to
Create a public method in your Activity class which returns a View with the given id.
public View getViewById(int id) {
return findViewById(id);
}
Use this method in your Fragment by doing so
((MainActivity) getActivity()).getViewById(R.id.button1)
Other approaches involve using Interfaces which I am sure you will learn about as you continue learning more.
Just to wrap things up, you have two ways to go about fixing your issue. Either move the buttons to the fragment layout files or create a public method to retrieve those views.

java.lang.RuntimeException: Unable to start activity android.view.InflateException: Binary XML file line #13

I'm new at learning Android. I'll be short. I'm receiving the error as mentioned at the bottom. I've added a fragment via XML. I've searched for solutions but none worked so far. Where am I going wrong?
If I can be pointed to a solution that's okay. May I get an explanation as to why this happens?
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.workout, PID: 7653
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.workout/com.example.workout.DetailActivity}: android.view.InflateException: Binary XML file line #9: Binary XML file line #9: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2969)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3047)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1777)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:166)
at android.app.ActivityThread.main(ActivityThread.java:6861)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:450)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)
Caused by: android.view.InflateException: Binary XML file line #9: Binary XML file line #9: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #9: Error inflating class fragment
Caused by: java.lang.IllegalArgumentException: Binary XML file line #9: Must specify unique android:id, android:tag, or have a parent with an id for com.example.workout.WorkoutDetailFragment
at androidx.fragment.app.FragmentManagerImpl.onCreateView(FragmentManagerImpl.java:3177)
at androidx.fragment.app.FragmentController.onCreateView(FragmentController.java:134)
at androidx.fragment.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:357)
at androidx.fragment.app.FragmentActivity.onCreateView(FragmentActivity.java:336)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:791)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:741)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:874)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:835)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:555)
at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:161)
at com.example.workout.DetailActivity.onCreate(DetailActivity.java:12)
at android.app.Activity.performCreate(Activity.java:7110)
at android.app.Activity.performCreate(Activity.java:7101)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2922)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3047)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1777)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:166)
at android.app.ActivityThread.main(ActivityThread.java:6861)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:450)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)
DetailActivity Xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
tools:context=".DetailActivity">
<fragment
class="com.example.workout.WorkoutDetailFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
DetailActivity Java
package com.example.workout;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
public class DetailActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detail);
}
}
Fragment xml
<!-- TODO: Update blank fragment layout -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:id="#+id/textTitle"
android:text="#string/workout_title"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/textDescription"
android:text="#string/workout_description"/>
</LinearLayout>
MainActivity Java
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onShowDetails(View view){
Intent intent = new Intent(this, DetailActivity.class);
startActivity(intent);
}
}

fix your detail_activity.xml replace class by android:name
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
tools:context=".DetailActivity">
<fragment
android:name="com.example.workout.WorkoutDetailFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</androidx.constraintlayout.widget.ConstraintLayout>

Modify your DetailActivity.xml tag fragment as follow
<fragment android:name="com.example.workout.WorkoutDetailFragment"
android:id="#+id/frag"
android:layout_weight="1"
android:layout_width="match_parent"
android:layout_height="match_parent" />

Implement your main activity with OnFragmentInteractionListener and change xml as per below code
public class MainActivity extends AppCompatActivity implements WorkoutDetailFragment.OnFragmentInteractionListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.detail_activity);
}
#Override
public void onFragmentInteraction(Uri uri) {
}}
And your XML
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
tools:context=".MainActivity">
<fragment
android:id="#+id/fragment"
android:name="com.example.myapplication.WorkoutDetailFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Share Fragment class file if you still can't execute

Please specify the unique id for your fragment and try.
<fragment
android:id="#+id/fragId"
class="com.example.workout.WorkoutDetailFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>

Fragment inflation from different flavors

I am learning Android and I cannot find the solution to a fragment instantiation error when they are in different flavors.
Setup:
I have a main fragment that is loaded into the main activity.
I have two favors: paid and free.
The main (common) part of the app doesn't have the fragment (layout + java files), I put them into the favors.
I get the following error when I try to run my program:
01-24 19:38:06.211 27417-27417/com.udacity.gradle.builditbigger.paid E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.udacity.gradle.builditbigger.paid, PID: 27417
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.udacity.gradle.builditbigger.paid/com.udacity.gradle.builditbigger.MainActivity}: android.view.InflateException: Binary XML file line #1: Binary XML file line #1: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: android.view.InflateException: Binary XML file line #1: Binary XML file line #1: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #1: Error inflating class fragment
Caused by: java.lang.NullPointerException
at java.lang.VMClassLoader.findLoadedClass(Native Method)
at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:738)
at java.lang.ClassLoader.loadClass(ClassLoader.java:363)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at android.support.v4.app.Fragment.isSupportFragmentClass(Fragment.java:499)
at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:3637)
at android.support.v4.app.FragmentController.onCreateView(FragmentController.java:111)
at android.support.v4.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:338)
at android.support.v4.app.BaseFragmentActivityApi14.onCreateView(BaseFragmentActivityApi14.java:39)
at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:67)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:780)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at com.udacity.gradle.builditbigger.MainActivity.onCreate(MainActivity.java:14)
at android.app.Activity.performCreate(Activity.java:6975)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
I have tried many different versions of the fragment name because the error message tells me that the problem is with that, unfortunately none of them worked. Could you please help me to find the route cause of the issue (I mean not just the solution but why doesn't this work)? The code can be found on GitHub, but the relevant files are here:
src/java/com/udacity/gradle/builditbigger/MainActivity.java
package com.udacity.gradle.builditbigger;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public void tellJoke(View view) {
new EndpointsAsyncTask().execute(this);
}
}
src/res/layout/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:layout_width="match_parent"
android:layout_height="match_parent"
tools:layout="#layout/fragment_main" />
src/free/java/com/udacity/gradle/builditbigger/free/MainActivityFragment.java
package com.udacity.gradle.builditbigger.free;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.udacity.gradle.builditbigger.R;
/**
* A placeholder fragment containing a simple view.
*/
public class MainActivityFragment extends Fragment {
public MainActivityFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_main, container, false);
AdView mAdView = (AdView) root.findViewById(R.id.adView);
// Create an ad request. Check logcat output for the hashed device ID to
// get test ads on a physical device. e.g.
// "Use AdRequest.Builder.addTestDevice("ABCDEF012345") to get test ads on this device."
AdRequest adRequest = new AdRequest.Builder()
.addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
.build();
mAdView.loadAd(adRequest);
return root;
}
}
src/free/res/layout/fragment_main.xml
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.udacity.gradle.builditbigger.MainActivity">
<TextView
android:id="#+id/instructions_text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/instructions" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/instructions_text_view"
android:onClick="tellJoke"
android:text="#string/button_text" />
<com.google.android.gms.ads.AdView
android:id="#+id/adView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
ads:adSize="BANNER"
ads:adUnitId="#string/banner_ad_unit_id" />
</RelativeLayout>
src/paid/java/com/udacity/gradle/builditbigger/paid/MainActivityFragment.java
package com.udacity.gradle.builditbigger.paid;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.udacity.gradle.builditbigger.R;
/**
* A placeholder fragment containing a simple view.
*/
public class MainActivityFragment extends Fragment {
public MainActivityFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_main, container, false);
return root;
}
}
src/paid/res/layout/fragment_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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.udacity.gradle.builditbigger.MainActivity">
<TextView
android:id="#+id/instructions_text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/instructions" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/instructions_text_view"
android:onClick="tellJoke"
android:text="#string/button_text" />
</RelativeLayout>

Meanwhile, I found the solution. In src/res/layout/activity_main.xml you need to give the android:name attribute to the fragment in order to make it work. The name is the same in both flavors (MainActivityFragment), but the namespaces are different (free and paid). The only way to resolve this issue is that you need to move this layout file to the flavor parts of the application, and delete the original from the main part. Long story short, you have to delete the src/res/layout/activity_main.xml file, and add these two files to the project:
src/free/res/layout/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.udacity.gradle.builditbigger.free.MainActivityFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:layout="#layout/fragment_main" />
src/paid/res/layout/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.udacity.gradle.builditbigger.paid.MainActivityFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:layout="#layout/fragment_main" />
I am sorry for the original question, but I hope that it will be useful for someone.

Android Studio Intent Not working

i am trying to start a new activity when a user click a imageView...
the imageView is on CardView.
I have added the Intent to the .java but still the app crashes..
here is my code
package com.example.rishav.thisiscarsearch20;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
public class MarutiSuzukiScrollingActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.content_maruti_suzuki_scrolling);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
public void onBaleno (View view){
Intent baleno = new Intent(this, LoginActivity.class);
startActivity(baleno);
}
}
XML
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.NestedScrollView 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"
android:background="#drawable/onmarutiselectcars"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.example.rishav.thisiscarsearch20.MarutiSuzukiScrollingActivity">
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:paddingBottom="8dp"
app:cardCornerRadius="10dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/textView12"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="8dp"
android:layout_marginBottom="8dp"
android:text="Maruti Baleno"
android:textAlignment="center"
android:textSize="20sp"
android:textStyle="normal|bold" />
<ImageView
android:id="#+id/baleno01"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/balenointro"
android:onClick="onBaleno" />
<TextView
android:id="#+id/textview01"
android:layout_width="273dp"
android:layout_height="wrap_content"
android:layout_margin="8dp"
android:text="Price : 5.3 - 8.7 Lakh"
android:textSize="18sp" />
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
when i run this on emulator i get the following error
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.rishav.thisiscarsearch20, PID: 2407
java.lang.IllegalStateException: Could not find method please(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatImageView with id 'baleno01'
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.resolveMethod(AppCompatViewInflater.java:327)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:284)
at android.view.View.performClick(View.java:5198)
at android.view.View$PerformClick.run(View.java:21147)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

public void onBaleno (View view){
Intent baleno = new Intent(getApplicationContext(), LoginActivity.class);
startActivity(baleno);
}
Hope it helps!

bro i was also getting the same problem, so i made another activity and used the intent to visit the new activity and it works for that one so i just copies the content to new activity and i notice while coping from the old activity that import (toolbar) was showing not being used so i didn't copied that and content related to that and it is working..