ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Using the drawing API
var mySprite:Sprite = new Sprite();
mySprite.graphics.beginFill(0xFFCC00);
mySprite.graphics.drawCircle(30, 30, 30);
var label:TextField = new TextField();
label.width = 200;
label.text = "They call me mellow yellow...";
label.x = 20;
label.y = 20;
mySprite.addChild(label);
this.addChild(mySprite);
Note that the TextField appears on top of the circle drawn with the graphics object.
Creating gradient lines and fills
Flash Player 9 and later, Adobe AIR 1.0 and later
The graphics object can also draw strokes and fills with gradients rather than solid colors. A gradient stroke is created
with the lineGradientStyle() method and a gradient fill is created with the beginGradientFill() method.
Both methods accept the same parameters. The first four are required: type, colors, alphas, and ratios. The remaining
four are optional but are useful for advanced customizing.
The first parameter specifies the type of gradient you are creating. Acceptable values are GradientType.LINEAR or
GradientType.RADIAL.
The second parameter specifies the array of the color values to use. In a linear gradient, the colors will be arranged
from left to right. In a radial gradient, they will be arranged from inside to outside. The order of the colors of the
array represents the order that the colors will be drawn in the gradient.
The third parameter specifies the alpha transparency values of the corresponding colors in the previous parameter.
The fourth parameter specifies ratios, or the emphasis each color has within the gradient. Acceptable values range
from 0-255. These values do not represent any width or height, but rather the position within the gradient; 0
represents the beginning of the gradient, 255 represents the end of the gradient. The array of ratios must increase
sequentially and have the same number of entries as both the color and alpha arrays specified in the second and
third parameters.
Although the fifth parameter, the transformation matrix, is optional, it is commonly used because it provides an easy
and powerful way to control the gradient’s appearance. This parameter accepts a Matrix instance. The easiest way to
create a Matrix object for a gradient is to use the Matrix class’s createGradientBox() method.
Defining a Matrix object for use with a gradient
Flash Player 9 and later, Adobe AIR 1.0 and later
You use the beginGradientFill() and lineGradientStyle() methods of the flash.display.Graphics class to define
gradients for use in shapes. When you define a gradient, you supply a matrix as one of the parameters of these methods.
Last updated 6/6/2012
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