ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
How to Use ActionScript Examples
Stage size
The stage size you use when running an example on a mobile device is much smaller than when you use a non-mobile
device. Many examples do not require a particular Stage size. When creating the SWF file, specify a Stage size
appropriate to your device. For example, specify 176 x 208 pixels.
The purpose of the practical examples in the ActionScript 3.0 Development Guide is to illustrate different ActionScript
3.0 concepts and classes. Their user interfaces are designed to look good and work well on a desktop or laptop
computer. Although the examples work on mobile devices, the Stage size and user interface design is not suitable to
the small screen. Adobe recommends that you run the practical examples on a computer to learn the ActionScript, and
then use pertinent code snippets in your mobile applications.
Text fields instead of trace statements
When running an example on a mobile device, you cannot see the output from the example’s trace statements. To see
the output, create an instance of the TextField class. Then, append the text from the trace statements to the text
property of the text field.
You can use the following function to set up a text field to use for tracing:
function createTracingTextField(x:Number, y:Number,
width:Number, height:Number):TextField {
}
var tracingTF:TextField = new TextField();
tracingTF.x = x;
tracingTF.y = y;
tracingTF.width = width;
tracingTF.height = height;
// A border lets you more easily see the area the text field covers.
tracingTF.border = true;
// Left justifying means that the right side of the text field is automatically
// resized if a line of text is wider than the width of the text field.
// The bottom is also automatically resized if the number of lines of text
// exceed the length of the text field.
tracingTF.autoSize = TextFieldAutoSize.LEFT;
// Use a text size that works well on the device.
var myFormat:TextFormat = new TextFormat();
myFormat.size = 18;
tracingTF.defaultTextFormat = myFormat;
addChild(tracingTF);
return tracingTF;
For example, add this function to the document class as a private function. Then, in other methods of the document
class, trace data with code like the following:
var traceField:TextField = createTracingTextField(10, 10, 150, 150);
// Use the newline character "\n" to force the text to the next line.
traceField.appendText("data to trace\n");
traceField.appendText("more data to trace\n");
// Use the following line to clear the text field.
traceField.appendText("");
Last updated 6/6/2012
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