--- HighlightedDatePicker.java---
import java.util.Map;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.DatePicker;



public class HighlightedDatePicker extends DatePicker {
	Rect mRect = new Rect();
   	
    public HighlightedDatePicker(Context arg0, AttributeSet arg1, Map arg2) {
    	super(arg0, arg1, arg2);
    	
    	/* Color is set by AA (alpha) then RRGGBB
    	 * I need to set the background to be transparent in order to paint
    	 * on the canvas background.  The background can also bet set to be a color,
    	 * and fully opaque
    	 */
    	this.setBackgroundColor(0x00FFFFFF);

    	/* Create a new Rectangle object each time the calendar is created
    	 * for testing purposes.
    	 */
    	mRect = new Rect((int)((float)Math.random() * 100),100,40,40);
    }

    @Override protected void onDraw(Canvas canvas) {
    	// Do the standard draw 
    	super.onDraw(canvas);
    	Paint paint = new Paint();
    	paint.setColor(Color.BLUE);  	
    	canvas.drawRect(mRect, paint); 
    }
    
} 

----- ShowData.java----
import android.app.Activity;
import android.os.Bundle;



public class ShowData extends Activity {
	private HighlightedDatePicker dp;
	
    @Override
    public void onCreate(Bundle icicle) {
    	super.onCreate(icicle);
    	setContentView(R.layout.show_data);
    	
    	dp = (HighlightedDatePicker) this.findViewById(R.id.super_date);    	
    	dp.init(2008, 3, 20, 1, null);
    	
    }

}

--res/layout/show_data.xml---
<?xml version="1.0" encoding="utf-8"?>

<AbsoluteLayout
android:id="@+id/widget166"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">


<com.foo.android.bar.HighlightedDatePicker
android:id="@+id/super_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_x="7px"
android:layout_y="8px" />