You might want to look at this method of the Effect class it should be able to give you what you want.
Set up your Effect, set the target(s) then call captureStartValues and then add your children and what not then call play. This will automatically figure out all of your tween values for you. public function captureStartValues():void Captures the current values of the relevant properties on the effect's targets. Flex automatically calls the captureStartValues() method when the effect is part of a transition. Use this function when you want the effect to figure out the start and end values of the effect. The proper usage of this function is to use it in the following steps: 1. Call the captureStartValues() method. The effect captures the starting effect values. 2. Make changes to your effect targets, such as adding/removing children, altering properties, changing location, or changing dimensions. 3. Call the play() method. The effect captures the end values. This function populates the EffectInstance.propertyChanges property for each effect instance created by this effect. Effect developers can use the propertyChanges property to retrieve the start and end values for their effect. --- In [email protected], "Ariel J" <arielj...@...> wrote: > > I am trying to write a custom container that can be handed a child component, > add it to the display list, and animate its own height from 0 to the height > of the child component so as to reveal it. > > Problem is, what do i set as the resize effect's heightTo value? I am trying > to call validateSize() on the child component before initializing and running > the resize effect from 0 to the child component's > getExplicitOrMesuredHeight() value but it is not working. > > What am I doing wrong? >
