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IJvDataItemsRenderer

Summary
Support interface for IJvDataItems that handles rendering and measuring of its items and their sub items.

Description
IJvDataItemsRenderer is an optional supporting interface for IJvDataItems that can handle the rendering and measuring of the items in the list.<br> <br> The interface provides methods to:<br> <br> * Draw an item given its index.<br> * Measure an item given its index.<br> * Draw the specified IJvDataItem instance.<br> * Measure the specified IJvDataItem instance.<br> * Determine the average item size.<br> <br> Some implementations of this interface will first check if the item to render or measure supports the<br> IJvDataItemRenderer interface; if it does, it will redirect the operation to that implementation instead of handling it itself.<br> <br> Consumers generally handle rendering/measuring in the following way:<br> <br> * Check if the item supports the IJvDataItemRenderer interface. If it does use it to perform the rendering/measuring.<br> * Check for the closest IJvDataItemsRenderer interface (the direct owning IJvDataItems list or any of the lists in its parent chain). If it finds one use it to perform the rendering/measuring.<br> * Handle the rendering at the consumer side. This means all items are considered equal and usually only IJvDataItemText and optionally IJvDataItemImage (and the corresponding IJvDataItemsImages) are<br> used. The entire rendering/measuring is then consumer (control) dependent and the provider tree may<br> no longer look uniform in different consumers/clients.<br>

See Also
IJvDataItemRenderer, IJvDataItems

Last changed by obones on 2009-01-04 21:13:59 CET

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