Last Updated: 29 Apr 2022 13:39 by ADMIN
Release R2 2022
Created on: 08 Jan 2021 09:58
Category: SplitContainer
Type: Bug Report
RadSplitContainer: problem in resizing split panels in design time in Net5

Dear Sir/Madam

Unfortunately, the SplitContainer in the .NET version 5 has problems, as you can see in the picture, I can not change the size in design time.

Is there a newer version that fixes this problem?

Telerik Winform Version :2020.3.1020

Visual Studio Version : 16.8.3

Best Regards



Attached Files:
Posted on: 06 Oct 2021 13:39

Hi Jean-Pierre,

Thanks for updating the issue. The suggested approach is a valid workaround for the current behavior.

In the R2 2021 SP1 we did some improvements in the splitters inside the .NET Core designer. Now, it is possible to move the splitters and resize the panels. The remaining issue is that it's necessary to drop the splitter on top of the split panel. In case the entire surface of the split panel is occupied by child controls, it will be necessary to rearrange them so that the splitter can be dropped.

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Posted on: 06 Oct 2021 10:05


My Telerik winform version 2021.3.914

I use a workaround for design time:

  • Undock the children controls
  • Move the split
  • ReDock the controls

Best regards

Posted on: 08 Jan 2021 18:41

Dear Dess

Thank you for your prompt reply 


Best Regards

Dess | Tech Support Engineer, Principal
Posted on: 08 Jan 2021 12:41

Hello, Hojjat,   

I confirm that in .NET Core 5 RadSplitContainer doesn't allow to move the splitter at design time. The same behavior seems to be observed for the standard MS SplitContainer.

We have reported this behavior to Microsoft and they are aware of it. We don't have control over the missing mouse messages at design time.

However, I have logged it in our feedback portal by making this thread public on your behalf. You can track its progress, subscribe for status changes and add your comments on the following link - feedback item.

I have also updated your Telerik points.

Due to the specificity of the issue I can't suggest an appropriate solution for the design time experience. Please excuse us for the inconvenience caused.

Dess | Tech Support Engineer, Sr.
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