Learning ActionScript 3.0, 2nd Edition

Chapter 5. Timeline Control

IN THIS CHAPTER

Jump Right In

Playhead Movement

Frame Labels

Frame Rate

A Simple Site or Application Structure

What’s Next?

In this chapter, you’ll learn some basic approaches to controlling timelines—both that of the main Flash movie and the movie clips it contains. We’ll divide our focus into three main areas:

• Jump Right In. Change the frame rate of your SWF at runtime.

• Playhead Movement. This includes stopping and playing the file, and going to a specific frame.

• Frame Labels. Including improved playhead movement techniques without relying on frame numbers.

• Frame Rates. Changing the movie’s frame rate to increase or decrease animation speed during playback.

• A Simple Site or Application Structure. We’ll wrap up the chapter by building a project that combines timeline animation with ActionScript navigation. The project can be used as an example template for a multistate application or Flash-based website.

We’ll also take a look at an undocumented feature that allows you to add frame scripts to movie clips at runtime and show you a demo of how to create a flexible structure for a Flash website or application.

Jump Right In

We’ll start off with one of the most-desired features in the evolution of ActionScript: the ability to adjust the frame rate of a file with code. Consider a simple example that switches a SWF’s frame rate between 1 and 24 frames per second, with every click of the mouse. This script can be found in the frame_rate_trace.fla source file.

1    stage.frameRate ...