How to Use Flash MX Sound Objects - Page 9

For this example, changing the volume for a looping background sound will be described. Unless you will have only one sound object, or you want to keep all sound objects at the same volume, the looping sound object will need to be associated with a unique movie clip as outlined in the previous section. Here are the steps:

1. Create an empty movie clip, drag it out onto the _root stage (or off stage), and give it an instance name such as "myLoopMc".
   
2. Import the sound file into the movie's library and set its linkage properties identifier to an appropriate name such as "myLoop01" (see Fig. 02).
   
3. Define the sound object on frame one of a layer, for example, called "Sound Objects" using an instance name such as "myLoop", and use the setVolume method to establish the volume level. A variable, "myLoopVolume" will be used to set the volume, so that it can be manipulated later.

The resulting sound object should appear as follows:

Volume for a sound object can be set between 0 and 100. In the above example, the volume is set to 50%. The setVolume can be placed in a variety of locations - on a button, in a function, on a frame within another movie clip on stage, etc. Just remember that if its placed any place besides the _root level (as that is where the sound object was initially defined), the path to where it was defined needs to be included as follows:

This method could be used to create a volume control knob or slider for your Flash audio interface. For example, if you wanted to include a volume slider, create a movie clip that can be dragged. Create a formula to have either its x or y axis values control the setVolume variable. As the axis increases or decreases, the volume percentage increases or decreases an equal amount. This is very simple for a horizontal slider.