Look in to this example
http://w2davids.wordpress.com/android-simple-calendar/
If you change the layout background you will get what you want
You copy the below code and in button onclick call
Intent i=new Intent(MainActivity.this,SimpleCalendarViewActivity.class);
startActivity(i);
And in android Manifest File for SimpleCalendarViewActivity add this theme.. It will display this as a Dialog. check it out
android:theme="@android:style/Theme.Dialog"