Flash CS5: The Missing Manual

Timeline Stop and Go

Starting and stopping an animation is similar to hitting the Pause and Play buttons on a DVD player. If your audience is viewing your animation in the desktop version of Flash Player, then they can pause and play the animation by pressing Enter or Return, just as when you start and stop the playback when you're working in the Flash authoring environment. ActionScript gives you the tools to start and stop animations programmatically. There are all sorts of ways you can put this feature to use. Suppose you want the Stutz Bearcat to make a real stop at that stop sign, instead of the kind of stop that'll get you a ticket. You can place a stop() command in the timeline at the frame where you want the animation to stop.

Note

The stop() and go() examples in this section also use the car-driving frog graphics. If you're continuing to use your document from the previous exercises, delete the code on Frames 1 and 22 that changes the timeline speed. If you want to start with a new sample document, download 15-2_Timeline_ Stop_Go.fla from the Missing CD page at www.missingmanuals.com/cds.

Here's how to tell your animation when to stop using ActionScript:

1. Open 15-2_Timeline_Stop_Go.fla.

   The actions layer at the top of the timeline has keyframes at Frame 1 and Frame 22, but there's no code in the frames.

2. Right-click Frame 22, and then choose Actions from the shortcut menu.

   The Actions panel opens, and the current selection is set to Frame 22.

3. Type the following code:

   stop();

   This line ...