Modify /res/layout/activity_main.xml to define layout, with <fragment> of "com.google.android.youtube.player.YouTubePlayerFragment".
<LinearLayout 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"
    android:orientation="vertical"
    tools:context=".MainActivity" >
    <fragment
        android:name="com.google.android.youtube.player.YouTubePlayerFragment"
        android:id="@+id/youtubeplayerfragment"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
    
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="http://arteluzevida.blogspot.com/"
        android:textStyle="bold"
        android:layout_gravity="center_horizontal"
        android:autoLink="web" />
    
    <ScrollView 
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <LinearLayout 
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">
            <Button
                android:id="@+id/btnviewfullscreen"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="View in Full Screen" />
            <TextView 
                android:id="@+id/videolog"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            
        </LinearLayout>
    </ScrollView>
    
</LinearLayout>
Create /res/layout-land/activity_main.xml to define layout in Landscape orientation.
<LinearLayout 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"
    android:orientation="horizontal"
    tools:context=".MainActivity" >
    <fragment
        android:name="com.google.android.youtube.player.YouTubePlayerFragment"
        android:id="@+id/youtubeplayerfragment"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="3"/>
    <LinearLayout 
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_weight="1">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="http://arteluzevida.blogspot.com/"
            android:textStyle="bold"
            android:layout_gravity="center_horizontal"
            android:autoLink="web" />
        
        <ScrollView 
            android:layout_width="match_parent"
            android:layout_height="match_parent">
            <LinearLayout 
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical">
                <Button
                    android:id="@+id/btnviewfullscreen"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:text="View in Full Screen" />
                <TextView 
                    android:id="@+id/videolog"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content" />
            </LinearLayout>
  </ScrollView>
    </LinearLayout>
</LinearLayout>
MainActivity.java
package com.example.androidyoutubeapiplayer;
import com.google.android.youtube.player.YouTubeBaseActivity;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubePlayer;
import com.google.android.youtube.player.YouTubePlayer.PlaybackEventListener;
import com.google.android.youtube.player.YouTubePlayerFragment;
import com.google.android.youtube.player.YouTubePlayer.PlayerStateChangeListener;
import com.google.android.youtube.player.YouTubePlayer.Provider;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends YouTubeBaseActivity implements 
 YouTubePlayer.OnInitializedListener{
 
 public static final String API_KEY = "AIzaSyCe6tORd9Ch4lx-9Ku5SQ476uS9OtZYsWA";
 public static final String VIDEO_ID = "o7VVHhK9zf0";
 
 private YouTubePlayer youTubePlayer;
 private YouTubePlayerFragment youTubePlayerFragment;
 private TextView textVideoLog;
 private Button btnViewFullScreen;
 
 private static final int RQS_ErrorDialog = 1;
 
 private MyPlayerStateChangeListener myPlayerStateChangeListener;
 private MyPlaybackEventListener myPlaybackEventListener;
 
 String log = "";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        youTubePlayerFragment = (YouTubePlayerFragment)getFragmentManager()
             .findFragmentById(R.id.youtubeplayerfragment);
        youTubePlayerFragment.initialize(API_KEY, this);
        textVideoLog = (TextView)findViewById(R.id.videolog);
        
        myPlayerStateChangeListener = new MyPlayerStateChangeListener();
        myPlaybackEventListener = new MyPlaybackEventListener();
        
        btnViewFullScreen = (Button)findViewById(R.id.btnviewfullscreen);
        btnViewFullScreen.setOnClickListener(new OnClickListener(){
   @Override
   public void onClick(View arg0) {
    youTubePlayer.setFullscreen(true);
   }});
    }
 @Override
 public void onInitializationFailure(Provider provider,
   YouTubeInitializationResult result) {
  
  if (result.isUserRecoverableError()) {
   result.getErrorDialog(this, RQS_ErrorDialog).show(); 
  } else {
   Toast.makeText(this, 
     "YouTubePlayer.onInitializationFailure(): " + result.toString(), 
     Toast.LENGTH_LONG).show(); 
  }
 }
 @Override
 public void onInitializationSuccess(Provider provider, YouTubePlayer player,
   boolean wasRestored) {
  
  youTubePlayer = player;
  
  Toast.makeText(getApplicationContext(), 
    "YouTubePlayer.onInitializationSuccess()", 
    Toast.LENGTH_LONG).show();
  
  youTubePlayer.setPlayerStateChangeListener(myPlayerStateChangeListener);
  youTubePlayer.setPlaybackEventListener(myPlaybackEventListener);
  
  if (!wasRestored) {
        player.cueVideo(VIDEO_ID);
      }
 }
 
 private final class MyPlayerStateChangeListener implements PlayerStateChangeListener {
  
  private void updateLog(String prompt){
   log +=  "MyPlayerStateChangeListener" + "\n" + 
     prompt + "\n\n=====";
   textVideoLog.setText(log);
  };
  @Override
  public void onAdStarted() {
   updateLog("onAdStarted()");
  }
  @Override
  public void onError(
    com.google.android.youtube.player.YouTubePlayer.ErrorReason arg0) {
   updateLog("onError(): " + arg0.toString());
  }
  @Override
  public void onLoaded(String arg0) {
   updateLog("onLoaded(): " + arg0);
  }
  @Override
  public void onLoading() {
   updateLog("onLoading()");
  }
  @Override
  public void onVideoEnded() {
   updateLog("onVideoEnded()");
  }
  @Override
  public void onVideoStarted() {
   updateLog("onVideoStarted()");
  }
  
 }
 
 private final class MyPlaybackEventListener implements PlaybackEventListener {
  
  private void updateLog(String prompt){
   log +=  "MyPlaybackEventListener" + "\n-" + 
     prompt + "\n\n=====";
   textVideoLog.setText(log);
  };
  @Override
  public void onBuffering(boolean arg0) {
   updateLog("onBuffering(): " + String.valueOf(arg0));
  }
  @Override
  public void onPaused() {
   updateLog("onPaused()");
  }
  @Override
  public void onPlaying() {
   updateLog("onPlaying()");
  }
  @Override
  public void onSeekTo(int arg0) {
   updateLog("onSeekTo(): " + String.valueOf(arg0));
  }
  @Override
  public void onStopped() {
   updateLog("onStopped()");
  }
  
 }
}
 Download the files.
Download the files.Download APK to try on your device.
The tutorial: YouTube Android Player API step-by-step


 










