ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Display programming
The GeometricSprite class and its subclasses
Each display object the user can add to the canvas is an instance of one of the following subclasses of the
GeometricSprite class:
CircleSprite
SquareSprite
TriangleSprite
The GeometricSprite class extends the flash.display.Sprite class:
public class GeometricSprite extends Sprite
The GeometricSprite class includes a number of properties common to all GeometricSprite objects. These are set in
the constructor function based on parameters passed to the function. For example:
this.size = size;
this.lineColor = lColor;
this.fillColor = fColor;
The geometricShape property of the GeometricSprite class defines an IGeometricShape interface, which defines the
mathematical properties, but not the visual properties, of the shape. The classes that implement the IGeometricShape
interface are defined in the GeometricShapes sample application described in Learning ActionScript 3.0.
The GeometricSprite class defines the drawShape() method, which is further refined in the override definitions in
each subclass of GeometricSprite. For more information, see the “Adding display objects to the canvas” section, which
follows.
The GeometricSprite class also provides the following methods:
The onMouseDown() and onMouseUp() methods, which are described in “Clicking and dragging display objects”
on page 207
The showSelected() and hideSelected() methods, which are described in “Clicking and dragging display
objects” on page 207
Adding display objects to the canvas
Flash Player 9 and later, Adobe AIR 1.0 and later
When the user clicks the Add Shape button, the application calls the addShape() method of the DrawingCanvas class.
It instantiates a new GeometricSprite by calling the appropriate constructor function of one of the GeometricSprite
subclasses, as the following example shows:
Last updated 6/6/2012
205