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This article is about what the relationship between Flex and Flash is. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

Flex Flash relation analysis

1. The life cycle of Flex applications

Flex applications are basically Flash applications, but they are developed based on FlexFramework (written by ActionScript). The root object of the Flex application is SystemManager (not the Application root element we see in the flex application). It inherits from flash.dispaly.MovieClip-flashplayerdisplaytype,MovieClip is an object that supports the basic element frame frame of timeline. In FlexFramework, SystemManager is special and contains two frames (other component are all in one frame). The preloader and the real Application,preloader frame can be downloaded quickly and used to show the download progress of the application. Once the SystemManager instance of the Flex application enters the second frame The application instance of the Flex master application will be created and its own attribute application (null before entering the second frame) will be assigned, and the internal life cycle and events of the application (flex master application) will start to operate:

◆ preinitialize:application has been instantiated but no childcomponent has been created

◆ initialize: childcomponent has been created but laid out (layout)

◆ creationComplete:application has completed instantiation and completed the layout of all childcomponent

SystemManager has a topLevelSystemManager object that points to an SystemManager instance, which is the root of everything currently running in flashplayer. If flex is loaded into flashplayer as the main application, the above properties will point to itself (self-refrencing), but when the flex application is loaded by another flex application, its own SystmenManager topLevelSystemManager property is not self-referenced, but points to the SystemManager instance of its parent application. All subclasses of UIComponent have a systemManager attribute that points to the SystemManager instance of the application. When the event of the component listened to by the SystemManger instance bubbles, it will have the right to handle the event handling chain.

2. The difference between Flashpalyer and Framwork

Flashplayer is the running environment of Flex application and flash application, and the two applications have completely equal operation rights (through the API provided by Flashplayer). The .swf file formed by the two applications is the same performance in flashplayer, the difference is not the content of the application but the way they are created. Flex's Framework provides a layer of abstraction for applications between development and running. When Flex applications compile, the necessary framworklibrary will be compiled into .swf files (also affecting the size of application files, etc.). Of course, the main flashplayerclass will not be compiled into .swf, because they already exist in flashplayer, resulting in the same instructions that flashplayer can understand as flash applications.

It is convenient to distinguish between flashplayerclass and flexframework. The class of the former begins with flash, such as flash.net.URLLoader, while the latter begins with mx, such as mx.controls.Button.

3. Dynamically load other flex applications

The content attribute of Swfloader points to the SystemManager instance of the loaded flex application (its application attribute points to the Application instance of the loaded felx application). When swfloader loads and initializes the loaded flex application, it will dispatch the init event, which can be the same as the ApplicationComplete event that listens to the SystemManager instance loaded into the flex application. When the event occurs, the Application object loaded into content can refer to it.

And event.target.content.addEventListener (FlexEvent.APPLICATION_COMPLETE,func) in inithandler

With event.target.application.method in applicationCompleteHandler...

4. Understand the application domain (applicationdomain)

An application domain (similar to. Net appdoamin) has related class definitions, resources, etc. The loaded new flex application can exist in a new, isolated domain (taking up additional memory resources), in the child doamin of the current domain (sharing the resources of the parent domain, class definition, note that the class definition is replaced), or directly with the current doamin (also note that the class definition conflicts) Such as runtimesharedlibrary.

Implement the application of these three ways in the code (mainly applied to flash.system.LoaderContext, flash.display.Loader or flash.net.URLLoader, flash.system.ApplicationDomain)

Varcontext:LoaderContext=newLoaderContext (); context.applicationDomain=newApplicationDomain (ApplicationDomain.currentDomain); / / load as a child domain context.applicationDomain=newApplicationDomain (); / / load as a new domain context.applicationDomain=ApplicationDomain.currentDomain;// into the current domain varrequest:URLRequest=newURLRequest ("RuntimeLoadingExample.swf"); varloader:Loader=newLoader (); loader.load (request,context)

5. About preloader

Preloader is a lightweight class. When the * frame of systemManager is instantiated, preloader will dispatch a series of events, and progressbar listens to implement the loading interface. Once the application enters the second frame to be initialized by application, the initialization progress will be notified by systemmanager, and preloader will inform systemmanager that it is ready to be deleted.

Event dispatch for Preloader:

Progress Indicatesdownloadprogress complete Indicatesthatthedownloadiscomplete rslError Indicatesthataruntimesharedlibrarycouldnotload rslProgress Indicatesthedownloadprogressforaruntimesharedlibrary rslComplete Indicatesthatthedownloadiscompleteforruntimesharedlibraries initProgress Indicatesthattheapplicationisinitializing initComplete Indicatesthattheapplicationhasinitialized

Thus, preloader can be customized.

Thank you for reading! This is the end of the article on "what is the relationship between Flex and Flash". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it for more people to see!

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