THanks Clay. The sample works nicely, but it seems there is no FreezePainting property in C#, did I miss something?
>I don''t know of a easy way to handle this.
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>One solution is to freeze the painting on the form using interop. This techique is discussed in one of our Windows Forms FAQs,
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>http://www.syncfusion.com/faq/winforms/search/637.asp
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Here is a different sample. This sample keeps the expand states the same before and after a sort. In order to prevent the flash of the root level collapsing with the sort, the drawing is frozen. It adds a new property to your derived grid to feeze the screen painting through a Win32 API call.
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>(These type of problem go away in the new 2.0 GridGroupingControl.)
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