Managing movie clip depths

Every movie clip has its own z-order space that determines how objects overlap within its parent SWF file or movie clip. Every movie clip has an associated depth value, which determines if it renders in front of or behind other movie clips in the same movie clip timeline. When you create a movie clip at runtime by using attachMovie (MovieClip.attachMovie method), duplicateMovieClip (MovieClip.duplicateMovieClip method), or createEmptyMovieClip (MovieClip.createEmptyMovieClip method), you always specify a depth for the new clip as a method parameter. For example, the following code attaches a new movie clip to the timeline of a movie clip named container_mc with a depth value of 10.

container_mc.attachMovie("symbolID", "clip1_mc", 10);

This example creates a new movie clip with a depth of 10 within the z-order space of container_mc.

The following code attaches two new movie clips to container_mc. The first clip, named clip1_mc, is rendered behind clip2_mc because it was assigned a lower depth value.

container_mc.attachMovie("symbolID", "clip1_mc", 10);
container_mc.attachMovie("symbolID", "clip2_mc", 15);

Depth values for movie clips can range from -16384 to 1048575. If you create or attach a new movie clip on a depth that already has a movie clip, the new or attached clip overwrites the existing content. To avoid this problem, use the MovieClip.getNextHighestDepth() method; however, do not use this method with components that use a different depth-management system. Instead, use DepthManager class with component instances.

The MovieClip class provides several methods for managing movie clip depths; for more information, see getNextHighestDepth (MovieClip.getNextHighestDepth method), getInstanceAtDepth (MovieClip.getInstanceAtDepth method), getDepth (MovieClip.getDepth method), and swapDepths (MovieClip.swapDepths method) in the ActionScript 2.0 Language Reference.

For more information on movie clip depths, see the following topics:

Version 8

Send me an e-mail when comments are added to this page | Comment Report

Current page: http://livedocs.adobe.com/flash/8/main/00001399.html