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And unlike the current Flex SDK, a parent does not watch its children’s display properties for changes, so if the height and/or width of some child object changes, the parent and its parent's may not re-layout.  You may have to dispatch a “layoutNeeded” event or use an MXML tag to cause the dispatching of a “layoutNeeded” event.  If we start to see common scenarios where everyone is setting up these update events, we may build them in somehow.  For example, the Image and ImageButton components force a layout in their parents when the image content arrives since that is a common pattern.

This fits with the FlexJS  “just-in-time” instead of “just-in-case” philosophy.  In the dozens of containers and components in FlexJSStore, only twelve 3 “layoutNeeded” events are required.

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