How to display grid lines in a flex 4 list?

I am newbie with Flex 4 (and Flex/AS in general). I am using a spark list control to display certain items with my custom Item Renderer. I am trying to achieve the following: (1) show a separating line between rows in my list control (2) even when not a single row has been added, I want a horizontal grid lines to be displayed in the background

I am not sure whether (1) and (2) can be achieved in one go. I can solve (1) by modifying my item renderer to have a border, I guess. But I want to know whether there is a better or more conventional way.

I开发者_Go百科 am not sure how to address (2).

Thanks!

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I would do it like you said , drawing a line at the bottom of the item renderer. As for (2), you could add a line directly on a custom list skin and remove it when the dataprovider is set