Actionscript Cookbook

13.1. Creating an Object to Control Sound

Problem

You want to control sounds at runtime.

Solution

Create a new movie clip to serve as the sound’s target and then pass a reference to that clip to the Sound( ) constructor function (to create a new Sound object). Alternatively, create and invoke a custom createNewSound( ) method that handles this process automatically.

Discussion

Sound objects enable you to load sounds, play sounds, and control the volume and panning of sounds within your Flash movies. A Sound object must target a movie clip (_root is also a valid target). The audio that is controlled must be placed in the movie clip’s timeline at authoring time or loaded into the movie clip at runtime using attachSound( ) or loadSound( ). In any case, it is possible for you to place/load multiple sounds into a single movie clip, but doing so is discouraged. The reason for this is that a Sound object controls the audio in the target movie clip as a whole, so it is not possible to control each of the sounds separately if they are all in the same movie clip. Therefore, it is better to place/load each sound into its own movie clip and create a separate Sound object to control each one.

When you create a new Sound object, specify a target movie clip. To control sounds in the current timeline, specify the keyword this as the target.

// Incorrect. This does not work properly. mySound0_sound = new Sound( ); // Correct. This targets the current timeline. mySound1_sound = new Sound(this); ...