Run transition between movieclips (swfs)

programming flash
1

I currently have a simple setup, with a few menu buttons, which on MouseEvent.CLICK, loads an individual external .swf into a container.

When I click from one menu button to another, content is loaded really quick. So I want to apply some sort of transition effect between loading the .swf’s, - could be some sort of mask effect or just some fading.

Lets say we’re using a fade effect and lets say menu1 is loaded, and I click menu2. Then I want to apply my transition (fade out) to run (fading out menu1), and when the fade out is done, I want to fade in my new content (menu2).

How on earth would I go about that?

My code:
[COLOR=#993300]

 [COLOR=#993300]var[/COLOR] loader:Loader=[COLOR=#993300]new[/COLOR] Loader[COLOR=#000000]([/COLOR][COLOR=#000000])[/COLOR];
 
menu1.[COLOR=#000000]addEventListener[/COLOR][COLOR=#000000]([/COLOR]MouseEvent.[COLOR=#000000]CLICK[/COLOR], menu1Click[COLOR=#000000])[/COLOR];
[COLOR=#993300]function[/COLOR] menu1Click[COLOR=#000000]([/COLOR]event:MouseEvent[COLOR=#000000])[/COLOR]:[COLOR=#993300]void[/COLOR] [COLOR=#000000]{[/COLOR]
[COLOR=#993300]var[/COLOR] request:URLRequest = [COLOR=#993300]new[/COLOR] URLRequest[COLOR=#000000]([/COLOR][COLOR=#0000ff]"swf1.swf"[/COLOR][COLOR=#000000])[/COLOR];
loader.[COLOR=#993300]load[/COLOR][COLOR=#000000]([/COLOR]request[COLOR=#000000])[/COLOR];
container.[COLOR=#000000]addChild[/COLOR][COLOR=#000000]([/COLOR]loader[COLOR=#000000])[/COLOR];
[COLOR=#000000]}[/COLOR]
 
menu2.[COLOR=#000000]addEventListener[/COLOR][COLOR=#000000]([/COLOR]MouseEvent.[COLOR=#000000]CLICK[/COLOR], menu2Click[COLOR=#000000])[/COLOR];
[COLOR=#993300]function[/COLOR] menu2Click[COLOR=#000000]([/COLOR]event:MouseEvent[COLOR=#000000])[/COLOR]:[COLOR=#993300]void[/COLOR] [COLOR=#000000]{[/COLOR]
[COLOR=#993300]var[/COLOR] request:URLRequest = [COLOR=#993300]new[/COLOR] URLRequest[COLOR=#000000]([/COLOR][COLOR=#0000ff]"swf2.swf"[/COLOR][COLOR=#000000])[/COLOR];
loader.[COLOR=#993300]load[/COLOR][COLOR=#000000]([/COLOR]request[COLOR=#000000])[/COLOR];
container.[COLOR=#000000]addChild[/COLOR][COLOR=#000000]([/COLOR]loader[COLOR=#000000])[/COLOR];
[COLOR=#000000]}[/COLOR]

[/COLOR]