gistfile1.as

public function Tag()
{
    super();
    invalidator = InvalidationManager.forComponent(this);
    invalidator.forProperty("node").commitFunctionIs(commitNode);
}

[Bindable]
public var node:XML;

// Called by IM during commitProperties if node has changed.
private function commitNode():void
{
    // Does some stuff
    //...
    invalidateDisplaylist();
}

// IM automatically watches "node" and invalidates this component
override protected function commitProperties():void
{
    super.commitProperties();
    invalidator.validateProperties();
}