ACTIONSCRIPT 3 Developer’s Guide en

Chapter 20: Basics of Working with text
Flash Player 9 and later, Adobe AIR 1.0 and later
To display text on the screen in Adobe® Flash® Player or Adobe® AIR, use an instance of the TextField class or use the
Flash Text Engine classes. These classes allow you to create, display, and format text. Alternatively, you can use the
Text Layout Framework (TLF) — a component library based on the Flash Text Engine classes, but designed for ease
of use. On mobile devices, you can use the StageText class for text input.
You can establish specific content for text fields, or designate the source for the text, and then set the appearance of
that text. You can also respond to user events as the user inputs text or clicks a hypertext link.
Both the TextField class and the Flash Text Engine classes allow you to display and manage text in Flash Player and
AIR.You can use the TextField class to create text objects for display and input. The TextField class provides the basis
for other text-based components, such as TextArea and TextInput. You can use the TextFormat class to set character
and paragraph formatting for TextField objects and you can apply Cascading Style Sheets (CSS) using the
Textfield.styleSheet property and the StyleSheet class. You can assign HTML-formatted text, which can contain
embedded media (movie clips, SWF files, GIF files, PNG files, and JPEG files), directly to a text field.
The Flash Text Engine, available starting with Flash Player 10 and Adobe AIR 1.5, provides low-level support for
sophisticated control of text metrics, formatting, and bi-directional text. It also offers improved text flow and enhanced
language support. While you can use the Flash Text Engine to create and manage text elements, it is primarily designed
as the foundation for creating text-handling components and requires greater programming expertise.The Text
Layout Framework, which includes a text-handling component based on the Flash Text Engine, provides an easier way
to use the advanced features of the new text engine. The Text Layout Framework is an extensible library built entirely
in ActionScript 3.0. You can use the existing TLF component, or use the framework to build your own text component.
The StageText class, available starting in AIR 3, provides a native text input field. Because this field is provided by the
device operating system, it provides the experience with which users of a device are most familiar. A StageText instance
is not a display object. Instead of adding it to the display list, you assign an instance a stage and a display area on that
stage called a viewport. The StageText instance displays in front of any display objects.
For more information on these topics, see:
“Using the TextField class” on page 373
“Using the Flash Text Engine” on page 397
“Using the Text Layout Framework” on page 426
Native text input with StageText
Important concepts and terms
The following reference list contains important terms involved with text handling:
Cascading style sheets A standard syntax for specifying styles and formatting for content that’s structured in XML (or
HTML) format.
Device font A font that is installed on the user’s machine.
Dynamic text field A text field whose contents can be changed by ActionScript but not by user input.
Embedded font A font that has its character outline data stored in the application SWF file.
Last updated 6/6/2012
371