public class Fragment1 extends Fragment {
...
}

<fragment android:id="@+id/f1"
            class="com.survivingwithandroid.fragment.Fragment1"
       android:layout_width="match_parent"
       android:layout_height="20dp"/>

<FrameLayout android:id="@+id/fl1"
       android:layout_width="match_parent"
       android:layout_height="200dp"/>

public class MainActivity extends Activity {
 
@Override
protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
 
  Fragment2 f2 = new Fragment2();
  FragmentTransaction ft = getFragmentManager().beginTransaction();
  ft.replace(R.id.fl1, f2);
  ft.commit();
}

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" 
  android:background="#00FF00" 
  android:orientation="vertical" > 
 
  <TextView 
    android:id="@+id/lblFragment1" 
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="This is fragment #1" 
    android:textColor="#000000" 
    android:textSize="25sp" /> 
 
</LinearLayout> 

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" 
  android:background="#FFFE00" 
  android:orientation="vertical" > 
 
  <TextView 
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="This is fragment #2" 
    android:textColor="#000000" 
    android:textSize="25sp" /> 
 
  <Button 
    android:id="@+id/btnGetText" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:onClick="onClick" 
    android:text="Get text in Fragment #1" 
    android:textColor="#000000" /> 
 
</LinearLayout> 

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" 
  android:orientation="horizontal" > 
 
  <fragment 
    android:id="@+id/fragment1" 
    android:name="net.learn2develop.Fragments.Fragment1" 
    android:layout_width="0px" 
    android:layout_height="match_parent" 
    android:layout_weight="1" /> 
 
  <fragment 
    android:id="@+id/fragment2" 
    android:name="net.learn2develop.Fragments.Fragment2" 
    android:layout_width="0px" 
    android:layout_height="match_parent" 
    android:layout_weight="1" /> 
 
</LinearLayout> 

package net.learn2develop.Fragments; 
 
import android.app.Activity; 
import android.app.Fragment; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
 
public class Fragment1 extends Fragment { 
  @Override 
  public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
 
    Log.d("Fragment 1", "onCreateView"); 
 
    // ---Inflate the layout for this fragment--- 
    return inflater.inflate(R.layout.fragment1, container, false); 
  } 
} 

package net.learn2develop.Fragments; 
 
import android.app.Fragment; 
import android.os.Bundle; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.Button; 
import android.widget.TextView; 
import android.widget.Toast; 
 
public class Fragment2 extends Fragment { 
  @Override 
  public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
    // ---Inflate the layout for this fragment--- 
    return inflater.inflate(R.layout.fragment2, container, false); 
  } 
}