Better link to the Roger’s Max demo is here – he refers to frame tag within the few last pages: http://blogs.adobe.com/rgonzalez/.

Basicaly it is just a reguest to call bootstrap manager which in turn will execute constructor. That in turn allows you to write your own initialization code/register with the application asynchronously. I believe the book excerpt explaining this in details was published by one of sys-con magazines – I can find only part one out of 2 or 3 here http://webddj.sys-con.com/read/295397.htm. Article tells you about underwater issues you have to be concerned about, but the process is quite straight forward.

Hope this helps
Anatole

Today I’ve looked into mx.core.Application class and found there interesting metadata called [Frame] and presented with the following code (I’ve included comment too for the sake of completeness):

//————————————–
// Other metadata
//————————————–

/**
* The frameworks must be initialized by SystemManager.
* This factoryClass will be automatically subclassed by any
* MXML applications that don’t explicitly specify a different
* factoryClass.
*/
[Frame(factoryClass="mx.managers.SystemManager")]

the second class where this metadata can be found is mx.core.SimpleApplication:

[Frame(factoryClass="mx.core.FlexApplicationBootstrap")]

I couldn’t find any explanation about Flex 2 [Frame] metatag nor in the documentation, neither in the web search results.

My opinion is that [Frame] metatag is used to add a frame into Flex application. In this case, Application and SimpleApplication classes use [Frame] metadata to add corresponding system managers into first frame as the starters of application initialization process. And this fits into your above explanation.

And probably this can be used to add new frames into Flex 2 application.

But my knowledge of Flex 2 Framework is not quite deep to make sure I’m right, so it is interesting what do you think about this [Frame] Flex 2 metadata?