Last Updated: 20 Jan 2020 12:06 by ADMIN
Release R1 2020 SP1 (LIB 2020_1_120)
Created on: 15 Jan 2020 20:01
Category: Dock
Type: Bug Report
RadDock: Crash after downloading latest version


I have downloaded the latest winform version today and launched my application.

I experienced an immediate crash while replacing a document container by a split container.

You can see the small piece of code and the insttruction which is causing the crash ....

Obviously it was working properly before upgrading ...

Can you help? I am now just stuck so a fix or a workaround would be useful...


Olivier D.


if (ctrlOutput == null)
                Telerik.WinControls.UI.RadSplitContainer mainSplitContainer = null;

                ctrlOutput = new ToolWindowOutput(sbOutput);

                var Output = new Telerik.WinControls.UI.Docking.ToolWindow();
                Output.Text = "Output";

                var toolTabStrip = new Telerik.WinControls.UI.Docking.ToolTabStrip();

                if (this.documentContainer1.Parent == this.radDock1)


                    this.radDock1.Controls.Remove(this.documentContainer1); <<<< CRASH HERE

                    // need to remplace document container by a split container
                    mainSplitContainer = new Telerik.WinControls.UI.RadSplitContainer();
                    mainSplitContainer.Orientation = System.Windows.Forms.Orientation.Horizontal;

                    mainSplitContainer = (Telerik.WinControls.UI.RadSplitContainer)this.documentContainer1.Parent;


1 comment
Dess | Tech Support Engineer, Sr.
Posted on: 16 Jan 2020 11:17

Hello, Olivier,    

Following the provided information I have prepared a sample project containing a RadDock and using your code snippet. I was able to observe the error message. Indeed, in the previous version it didn't crash.    

I have logged it in our feedback portal by making this thread public. 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.

Currently, the possible solution that I can suggest is to use the following custom implementation for the existing DocumentTabStrips in RadDock

        public class CustomDockTabStrip : DocumentTabStrip
            public override string ThemeClassName
                    return typeof(DocumentTabStrip).FullName;

            protected override void OnDockManagerChanged()
                if (this.DockManager != null)

        private void InitializeComponent()
            this.radDock1 = new Telerik.WinControls.UI.Docking.RadDock();
            this.documentContainer1 = new Telerik.WinControls.UI.Docking.DocumentContainer();
            this.documentWindow1 = new Telerik.WinControls.UI.Docking.DocumentWindow();
            this.documentTabStrip1 = new CustomDockTabStrip();
        //some other code

I hope this information helps. If you need any further assistance please don't hesitate to contact me. 

Dess | Tech Support Engineer, Sr.
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