Adding Special Effects

Circle: ActiveX Control, Lesson 5

Tip   If you prefer working from a printed tutorial, see Copying and Printing in MSDN Library Help for details about printing a lesson, a set of topics, or a single topic.

This lesson further evolves the functionality of the Circle control. A new behavior is introduced that produces special effects in response to mouse events at run time.

Note   You can find a finished example of this lesson's code in the CIRC2 sample source code directory.

When you click the left mouse button inside the circle, the control briefly flashes a different color. To implement this special effect, the control must respond to mouse events.

This lesson introduces a new custom member variable property called FlashColor. The value of the FlashColor property contains the color the control will flash when the left mouse button is clicked with the insertion point (or cursor) within the circle.

In this lesson, you will:

• Add the FlashColor property to the Circle control.
  
  
• Set the value of the default color for FlashColor.
  
  
• Implement code to respond to mouse events.
  
  
• Implement code to perform hit testing.
  
  
• Add the FlashColor function.