So, you've been able to tween various properties of objects in Flex ([node:1354]) to make them fade in and out and what have you, but how do you get that cute 'bounce' effect where the property overshoots the end value and takes a while to settle down ?
The answer is burried in the mx.effects.easing classes. What you do is assign the type of ease (I like either Bounce.easeOut or Elastic.easeOut) to the Tween after you create it:
import mx.effects.easing.Elastic;
t.easingFunction=mx.effects.easing.Elastic.easeOut;
Easy once you know how, eh ? You might want to read a slightly outdated article, but with some handy examples here or the more scary Adobe docs here.
Easing explorer
There is a much improved Easing explorer online these days: http://www.madeinflex.com/img/entries/2007/05/customeasingexplorer.html
It lets you adjust all the random numbers that go into making an Easing, and shows the result on screen, and you can run the resulting Easing with it too.
Tom
Note this works with non-Tween based effects, and obviously from MXML too, as shown below.
Though it appears you still need to import the 'Exponential' (or whatever) on the same page.
Tom