MACROMEDIA FLASH 8-DEVELOPING FLASH LITE 2.X, Руководство по разработке

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50 Working with Sound
Event and stream (synchronized) sound
Flash Lite 1.1 supports event and stream ( synchronized ) sound. Event sounds play
independently of the Timeline and continue to play until either the end of the sound buffer
has been reached, or the sound is stopped using ActionScript. Event sounds must download
completely before they begin playing.
Stream sounds are synchronized with the Timeline on which they reside and are often used to
synchronize audio with animation. Stream sounds stop when the playhead of the containing
Timeline is stopped. During playback, Flash Lite drops frames from the animation, if
required, to keep the sound playback synchronized with animation.
Only native Flash sound can be synchronized with the Timeline; you can use device sounds
only as event sounds. Flash Lite 1.0 supports only event sound.
Using device sound (Flash Professional
Only)
A device sound is a sound that is encoded in the device’s native audio format, such as MIDI or
MFi. The Flash authoring tool does not let you directly import device sound files into a Flash
document; rather, you first import a proxy sound in a supported format such as MP3, WAV,
or AIFF. You then link the proxy sound to an external mobile device sound, such as a MIDI
file. During the document publishing process, the proxy sound is replaced with the linked
external sound. The SWF file generated contains the external sound and uses it for playback
on a mobile device.
When using device sounds in Flash Lite, keep the following constraints in mind:
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Device sounds can only be used as event sounds; you can’t synchronize device sounds to
the Timeline.
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Flash Lite does not support the Effect, Sync, and Edit options for device sounds.
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You must specify an external device sound file for each sound in a document.
■
As with all external files, the device sound file or the sound bundle file must be available
when you publish your SWF file, but is not needed by the SWF file for playback.
You can also bundle multiple device sounds together in a single file. This is useful if you’re
creating the same content for several devices that support different device sound formats. For
more information, see
“Using compound sound (Flash Professional Only)” on page 54 .
In Flash Lite 1.1, a device sound can play at any time. In Flash Lite 1.0, a device sound can
only play in response to a user pressing a key on their device. For more information, see
“Triggering device sounds in Flash Lite 1.0” on page 53 .