Painting Issues

[Thiyagu]

Hi Clay,
I''m using GDBG grid. In that i''m having a column of type CheckBox. Here when I try to Reset/Save the Changes made to the Grid(by binding the Datasource freshely fetched from the Database), with the Focus on the any of the Check Box cells, the Grid is flickering to a great extent and also is taking bit more time to get repainted.

But it is not happening when I have the focus in any of the other cell types..

Please update me opn this Issuse.

Thanks in Advance,
Thiagu.

[Administrator]

Look in your ouput window to see if any exceptions are being thrown when this flickering happens.

One thing you can try is to call grid.BeginUpdate() before you change these values, and then call grid.EndUpdate() after you change the values, followed by a call to grid.Refresh() (- this last call may not be needed).

[Thiyagu]

No Expceptions are thrown. Also, I''m already using the grid.Beginupdate and Grid.endUpdate.. As I said, this works fine when I have the focus on any of the cells other checkbox cells while Clicking on Save/Reset. I cannot send you the sample as I''m developing fully dependent application which will not run independently.

Thanks,
Thiagu

>Look in your ouput window to see if any exceptions are being thrown when this flickering happens.
>
>One thing you can try is to call grid.BeginUpdate() before you change these values, and then call grid.EndUpdate() after you change the values, followed by a call to grid.Refresh() (- this last call may not be needed).

[Administrator]

I am sort of at a lost without being able to see and debug the problem.

Maybe calling grid.Binder.SuspendBinding before the update and grid.Binder.ResumeBinding after the update will avoid this problem.

If the grid is repainting even when you call grid.BeginUpdate, then this suggests that the grid is being reset some how. This might happen if the grid is sorted and chaning the values changes teh sort. The DataView raises a ListChanged.Reset event when it sorts itself. The grid will respond by cancelling the update. Is this checkbox column sorted?

There is another technique you can use to lock the painting. The technique is to add a property to the form (or grid) that you can set to freeze painting through a Win32 API. Here is a forum link that discusses how you can do this. http://64.78.18.34/Support/Forums/message.aspx?MessageID=11104

Once you have this property added to your form/grid, you could freeze the painting before you set the values, and then unfreeze it after you set the values. I expect this will avoid teh flickers that you see.