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Posted by: dung.itcdt on 4 December 2023, 7:05 pm EST
dung.itcdt
Posted 4 December 2023, 7:05 pm EST
When I scroll, the control doesn’t seem to refresh, leading to the same situation as in the video.
I tried switching DrawMode but still the same.
How do I fix this error?
Version I’m using: 20231.596
Scroll.rar
wknauf
Posted 4 December 2023, 7:27 pm EST
Hi,
I reported a similar issue (but maybe not the same I fear) some time ago, and it was fixed in 20232.620: https://developer.mescius.com/forums/winforms-edition/net6-c1flexgrid-allowmergingfixed-and-rendering-issue
Could you upgrade and check whether the problem disappears?
Best regards
Wolfgang
dung.itcdt
Posted 4 December 2023, 7:58 pm EST - Updated 4 December 2023, 7:58 pm EST
Hi,
I tried downloading the version as you instructed but still got the error. I’m using .NET Framework 4.8
wknauf
Posted 4 December 2023, 8:20 pm EST
Could you create a small standalone sample the reproduces the problem?
Best regards
Wolfgang
kartik.dua
Posted 5 December 2023, 5:52 pm EST
Hi Le,
Thank you for sharing the video. Unfortunately, we could not reproduce the issue on our end. Could you please share a stripped-down version of your project or a sample project showing the issue you are facing? This will greatly help us in investigating the behavior further and assisting you better.
We also suggest that you try your project with the latest version of C1FlexGrid available on NuGet (https://www.nuget.org/packages/C1.Win.C1FlexGrid/4.8.20233.631) and see if you still face the issue.
@Wolfgang, thank you for your input!
Best Regards,
Kartik
dung.itcdt
Posted 11 April 2024, 9:34 pm EST - Updated 11 April 2024, 9:39 pm EST
kartik.dua
Posted 14 April 2024, 7:12 pm EST
Hi,
Thank you for sharing all the details. We could see the behavior you mentioned in the FreezeBottom product sample. However, it seems like an implementation issue, where the grid is not being updated correctly in the SynchScrollPosition method of the custom FlexFreezeBottom class. To fix this, please update the code as shown in the attached screenshot (see CodeReplace.zip)
If your implementation is similar to the FreezeBottom product sample, please do the necessary changes to fix the behavior. If you are facing the issue with a different implementation, please provide a sample project reproducing the same, so we can investigate further and assist you better.
Attachment: CodeReplace.zip
Best Regards,
Kartik
dung.itcdt
Posted 15 April 2024, 11:55 am EST
Hi Kartik,
Thanks for providing a fix for this issue, but it has some problems. Calling Refresh like this will redraw all the controls in the form, which is unnecessary because I’m only scrolling each grid. I think the problem lies in the behavior when scrolling that the grid does not call invalidate again, or it could be due to miscalculation of the timing of calling invalidate in the grid.
I need to fix this issue directly within the C1.Win.C1FlexGrid dll, not outside the form, because the grid can be anywhere, on any form, and having to call Refresh again every time I scroll is not acceptable at all 
kartik.dua
Posted 15 April 2024, 5:03 pm EST
Hi,
The FreezeBottom is not an inbuilt feature of the C1FlexGrid. It is a custom implementation which requires the scrolling of the two C1FlexGrids to be handled manually, which is why it requires to be Refreshed manually after scrolling. Also, this implementation calls the Refresh method of only the two C1FlexGrids and it won’t Refresh all the controls on the form.
Note: Please note that the need to manual refresh after scrolling is specific to this custom implementation only and not when using the C1FlexGrid usually.
If you are using the FreezeBottom implementation in your application, then please use the fix we suggested in our previous response. Else, if you are facing this rendering issue in a different implementation, please provide a sample project reproducing the same, so we can investigate further and assist you in the best way possible.
Thanks, and Best Regards,
Kartik
