| << Chapter < Page | Chapter >> Page > |
Play an occasional sizzle sound
Listing 8 uses a similar process to play an occasional sizzle sound. Listing 8 also causes the sizzle sound to be followed immediately by a clap of thunder.
if ((loopCntr % 35 == 0)&&(Math.random()>0.5)&&(sizzlePlaying == false)) {
//Don't play another sizzle sound until this one// finishes.
sizzlePlaying = true;//Play the sizzle sound and get a reference to the// SoundChannel object through which it is being
// played.channel = sizzle.play();//Register an event listener that will be called
// when the sizzle sound finishes playing.channel.addEventListener(
Event.SOUND_COMPLETE, soundCompleteHandler);}//end if}//end onTimer Save the SoundChannel reference
Listing 8 saves the SoundChannel reference returned by the play method in an instance variable named channel when the play method is called to play the sizzle sound.
Don't corrupt the reference to the SoundChannel object
In order to preclude the possibility of corrupting this reference by changing its value while the sound is playing, Listing 8 uses a Boolean instance variable named sizzlePlaying to guarantee that a new sizzle sound is not played before the previous one finishes.
The value of sizzlePlaying is set to true when the sizzle sound starts playing in Listing 8 and is set to false later when the sizzlesound finishes playing. Because the value of sizzlePlaying is tested by the conditional clause in the if statement in Listing 8, that conditional clause will never return true while sizzlePlaying is true.
Register a SOUND_COMPLETE event handler
The SoundChannel object fires a SOUND_COMPLETE event when the sound that it is playing finishes. Listing 8 registers an eventlistener on the SoundChannel object that is called each time the sizzle sound finishes playing. As you will see shortly, the code in theevent handler sets the value of sizzlePlaying to false and also causes the thunder sound to be played as soon as the sizzle sound finishes.
The SOUND_COMPLETE event handler
The SOUND_COMPLETE event handler is shown in its entirety in Listing 9. This method is called each time the sizzle sound finishes playing.
private function soundCompleteHandler(e:Event):void {
//Allow another sizzle sound to be played now that// this one is finished.
sizzlePlaying = false;//Play the thunder immediately following the end of
// the sizzle sound.thunder.play();
}//end soundCompleteHandler//--------------------------------------------------//} //end class
} //end package Allow another sizzle sound to be played
Listing 9 begins by setting the value of sizzlePlaying to false. This makes it possible for the sizzle sound to be played again when theother two expressions in the conditional clause of the if statement in Listing 8 return true.
Play a thunder clap
Then Listing 9 calls the play method on the thunder sound to cause the thunder sound to be played once immediately following thecompletion of each sizzle sound.
Notification Switch
Would you like to follow the 'Object-oriented programming (oop) with actionscript' conversation and receive update notifications?
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|