<Button
  android:id="@+id/button5"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@string/fullscreen" 
  android:onClick="changescreen"/>

private static boolean isfull=true;
//全屏设置和退出全屏
private void setFullScreen(){
   //requestWindowFeature(Window.FEATURE_NO_TITLE); 
   getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
   isfull=true;
}
private void quitFullScreen(){
   final WindowManager.LayoutParams attrs = getWindow().getAttributes();
   attrs.flags &= (~WindowManager.LayoutParams.FLAG_FULLSCREEN);
   getWindow().setAttributes(attrs);
   getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
   //requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
   isfull=false;
}
public void changescreen(View view)
{
  if(isfull==true)
  {
   quitFullScreen();
  }
  else
  {
   setFullScreen();
  }
}

@Override
public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  // remove title bar  
  this.requestWindowFeature(Window.FEATURE_NO_TITLE); 
  // full screen 
  this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN); 
  setContentView(R.layout.main);
}