Tween: Property backgroundAlpha not found on mx.containers.VBox and there is no default value.

[San Kumar]

Hi,

 

I have a very simple application where I want to tween the `backgroundAlpha` of a VBox using TweenLite.

 

I'm using the following code:

TweenLite.to(box1, 2, {backgroundAlpha:0.4});

But when I try to run my movie, I get the following error:

Property backgroundAlpha not found on mx.containers.VBox and there is no default value.

I'm guessing it is because backgroundAlpha is set using `setStyle` not directly... so that is causing the issue?

 

So how do you do it in TweenLite or TweenMax to set it?

 

Thanks for your replies..

 

San

[GreenSock]

You could use a proxy object and an onUpdate:

var styles:Object = {backgroundAlpha:box1.getStyle("backgroundAlpha")};
TweenLite.to(styles, 2, {backgroundAlpha:0.4, onUpdate:function() {
    box1.setStyle("backgroundAlpha", styles.backgroundAlpha);
}});

Or create your own plugin that manages that stuff for you. 

[San Kumar]

Hi,

 

thanks so much for the reply.. I just wanted to make sure it wasn't anything i was doing wrong.

 

I can definitely write that plugin.. do you accept pull requests?

 

thanks

[GreenSock]

Unfortunately we generally don't accept pull requests because:

1. We have to stand behind whatever we offer to the community, so we must be intimately familiar with every line of code. 
2. Our licensing model requires that we make certain promises to our customers regarding authorship and protect them from IP infringement issues. Pull requests make that much more difficult or outright impossible. 

That being said, we do welcome pull requests for the purpose of seeing suggestions and ideas. Even if we don't merge the changes into our codebase, pull requests are great for communicating what you'd like to see in our toolset and sharing your approach.