you should use outerDocument.goToAlertTab() to call functions.
But's it's not the best variant to implement. It's better to dispath event from itemRenderer and set a special handler for it.
Thanks for your reply.
But I need some more explanation.
As evident from the method name, on this click event I need to switch to a different Tab named "Alert" in a TabBar. This TabBar resides 4 levels above the item renderer (This itemRenderer is in a DataGrid, which is in a Panel, which is in a TabNavigator, which is again in another TabNavigator that has Alert Tab). Can u please give some more explanation on how can I handle this situation by dispatching event.
This is evident that it's very difficult to go throw your hierarhy to change tab, dispatching event will be more easier.
There http://www.adobe.com/devnet/flex/articles/itemrenderers_pt1.html is a good example on dispatching events from itemRenderer an handling them.
Also may be useful for you to use states to navigate in application. Read docs to learn more about them.
Here are some links on dispatching custom events:
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