Data provider problem in custom item renderer

Question

I have a complex, custom item renderer for a list. I add
items that I extracted from an xml to the data provider using the
IList interface. But when displaying the list, the items are all
screwed up. Each rendered item has some parts which are initialized
as different components depending on the values from the xml. This
initialization is called in the item renderer for the
creationComplete event.
The weird thing is that when I output the dataProvider to
check its values, some of the items have internal uids sometimes
and sometimes they don't. If I output the dataProvider right after
I add the items to it, none of them get internal uids. But from the
initialize method, some of them do and some don't.
To make things weirder, sometimes, as I scroll up and down
the list, the dynamic components get all switched up. I'm either
having a problem with internal uids or with the creation policies
for lists. Or it's probably some simpler mistake I have yet to see.
Anyone have any idea where the problem could lie? Any help is
greatly appreciated.

Answer 1

Any successful render must:
1) override the set data property of the component
Further, best practice is to store any data you need in the
override set data(), and call invalidateProperties(). Then do the
actual work in an override commitProperties() function.
The framework is smart about when to call commitProperties
efficiently. set data() gets called much more often.
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