Adobe Flash Professional CC 2014 v.13.0 - Manual (Page 872)

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1. Select File > Publish Settings, and then click the Flash tab to display compression options.
2. Adjust the JPEG quality slider, or enter a value. A higher JPEG quality value produces an image of higher image quality but a larger SWF
file. A lower image quality produces a smaller SWF file. Try different settings to determine the best trade-off between size and quality.
Optimizing Flash Lite frames for mobile devices
Most devices that support Flash Liteplay back content at about 15 to 20 frames per second (fps). The frame rate can be as low as 6 fps.
During development, set the document frame rate to approximate the playback speed of the target device. This shows how the content will
run on a device with limited performance. Before publishing a final SWF file, set the document frame rate to at least 20 fps or higher to avoid
limiting performance in case the device supports a higher frame rate.
When using gotoAndPlay, remember that every frame between the current frame and the requested frame needs to be initialized before
Flash plays the requested frame. If many of these frames contain different content, it could be more efficient to use different movie clips
rather than using the Timeline.
Although preloading all content by putting it at the beginning of the file makes sense on the desktop, preloading on a mobile device can delay
file startup. Space content throughout the file so that movie clips are initialized as they are used.
For more tips and techniques for creating content for mobile phones and devices, see www.adobe.com/go/learn_cs_mobilewiki_en .
Optimizing ActionScript for Flash Lite content on mobile devices
Because of the processing speed and memory limitations on most mobile devices, follow these guidelines when developing ActionScript for Flash
Lite content used on mobile devices:
Keep the file and its code as simple as possible. Remove unused movie clips, delete unnecessary frame and code loops, and avoid too
many frames or extraneous frames.
Using FOR loops can be expensive because of the overhead incurred while the condition is checked with each iteration. When the costs of
the iteration and the loop overhead are comparable, execute multiple operations individually instead of using a loop. The code may be
longer, but performance will improve.
Stop frame-based looping as soon as it is no longer needed.
When possible, avoid string and array processing because it can be CPU-intensive.
Always try to access properties directly rather than using ActionScript getter and setter methods, which have more overhead than other
method calls.
Manage events wisely. Keep event listener arrays compact by using conditions to check whether a listener exists (is not null) before calling it.
Clear any active intervals by calling clearInterval, and remove any active listeners by calling removeListener before removing content using
unloadapplication or removeapplicationClip. Flash does not re-collect SWF data memory (for example, from intervals and listeners) if any
ActionScript functions are still referring to the SWF data when a movie clip is unloaded.
When variables are no longer needed, delete them or set them to null, which marks them for garbage collection. Deleting variables helps
optimize memory use during run time, because unneeded assets are removed from the SWF file. It is better to delete variables than to set
them to null.
Explicitly remove listeners from objects by calling removeListener before garbage collection.
If a function is being called dynamically and passing a fixed set of parameters, use call instead of apply.
Make namespaces (such as paths) more compact to reduce startup time. Every level in the package is compiled to an IF statement and
causes a new Object call, so having fewer levels in the path saves time. For example, a path with the levels
com.xxx.yyy.aaa.bbb.ccc.funtionName causes an object to be instantiated for com.xxx.yyy.aaa.bbb.ccc. Some Flash developers use
preprocessor software to reduce the path to a unique identifier, such as 58923409876.functionName, before compiling the SWF code.
If a file consists of multiple SWF files that use the same ActionScript classes, exclude those classes from select SWF files during compilation.
This can help reduce file download time and run-time memory requirements.
Avoid using Object.watch and Object.unwatch, because every change to an object property requires the player to determine whether a
change notification must be sent.
If ActionScript code that executes on a keyframe in the timeline requires more than 1 second to complete, consider splitting up that code to
execute over multiple keyframes.
Remove trace statements from the code when publishing the SWF file. To do this, select the Omit Trace Actions check box on the Flash tab
in the Publish Settings dialog box.
Inheritance increases the number of method calls and uses more memory: a class that includes all the functionality it needs is more efficient
at run time than a class that inherits some of its functionality from a superclass. Therefore, you may need to make a design trade-off between
extensibility of classes and efficiency of code.
When one SWF file loads another SWF file that contains a custom ActionScript class (for example, foo.bar.CustomClass) and then unloads
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