Flex 3 and Flex 4 - Tips

• When manually dispatching an event, using uiComponent.dispatchEvent(your-event), you need to add listener to the same component uiComponent. So, uiComponent.addEventListener(type,handler) will work, but uiAnyOtherComponent.addEventListener(type,handler) will not work.
• The state changes-related transition effects have to correspond to the type of changes between the corresponding states.
  Example: I had a vertical group with two components. In State 1, both components show. In State2, Comp1 is not included. I set a Resize transition for Comp1 and a Move transition for Comp2. The effect was surprising: when state changed, Comp1 disappeared and appeared at the bottom of the screen. There it was re-sized. The right fix was to change Comp1: instead of includeIn=State1, I did height.State2=0. That did the trick.

• Constraint-based layout is supported only in a container with BasicLayout. If you want to use it inside a VGroup, for example, you can put it inside a Group for which you don't specify any layout (BasicLayout is the default).