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Syncfusion Feedback

DockableWorkspace closing app exception

Thread ID:





79399 Feb 6,2009 10:14 AM UTC Sep 14,2009 11:37 AM UTC General Discussion 6
Tags: General Discussion
Administrator [Syncfusion]
Asked On February 6, 2009 10:14 AM UTC


I'm using syncfusion dockable workspace together with tabbed mdi one in a CAB/SCSF application. When I close the app, I have problems with dockable workspace (see stacktrace below), as a result I can't close my app properly.

System.NullReferenceException was unhandled by user code
Message="Object reference not set to an instance of an object."
at Syncfusion.Windows.Forms.Tools.DockHost.UnsubscribeDockHostEvents()
at Syncfusion.Windows.Forms.Tools.DockingManager.SetEnableDocking(Control ctrl, Boolean value)
at Syncfusion.CAB.WinForms.WorkSpaces.DockableWorkSpace.CloseDockedWindow(Control window)
at Syncfusion.CAB.WinForms.WorkSpaces.DockableWorkSpace.OnClose(Control smartPart)
at Microsoft.Practices.CompositeUI.SmartParts.Workspace`2.CloseInternal(TSmartPart smartPart)
at Microsoft.Practices.CompositeUI.SmartParts.Workspace`2.Close(Object smartPart)
at ECGSmartClient.Infrastructure.Interface.Presenter`1.CloseView()
at ECGSmartClient.ECGClient.UserEventsViewPresenter.OnCloseView()
at ECGSmartClient.Infrastructure.Interface.Presenter`1.Dispose(Boolean disposing)
at ECGSmartClient.Infrastructure.Interface.Presenter`1.Dispose()
at ECGSmartClient.ECGClient.UserEventsView.Dispose(Boolean disposing)
at System.ComponentModel.Component.Dispose()
at System.Windows.Forms.Control.Dispose(Boolean disposing)
at System.Windows.Forms.ContainerControl.Dispose(Boolean disposing)
at Syncfusion.Windows.Forms.Tools.DockHost.Dispose(Boolean bdisposing)
at System.ComponentModel.Component.Dispose()
at Syncfusion.Windows.Forms.Tools.DockHostController.Dispose(Boolean bdisposing)
at Syncfusion.Windows.Forms.Tools.SizingController.Dispose(Boolean bdisposing)
at Syncfusion.Windows.Forms.Tools.MainFormController.Dispose(Boolean bdisposing)
at Syncfusion.Windows.Forms.Tools.DockingManager.Dispose(Boolean bdisposing)
at System.ComponentModel.Component.Dispose()
at System.ComponentModel.Container.Dispose(Boolean disposing)
at System.ComponentModel.Container.Dispose()
at ECGSmartClient.Infrastructure.Shell.ECGShellForm.Dispose(Boolean disposing)
at System.ComponentModel.Component.Dispose()
at System.Windows.Forms.Form.WmClose(Message& m)
at System.Windows.Forms.Form.WndProc(Message& m)
at Syncfusion.Windows.Forms.Office2007Form.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Please advise.

Poly J [Syncfusion]
Replied On February 9, 2009 12:02 PM UTC

Hi Eugene,

If you are using latest public release version [] of Essential Studio, can you install the Cab Add on Set up from the below provided link.


Please let me know if you are still able to reproduce the issue, also let us know the version details of the set up you are using.

Best Regards,

Administrator [Syncfusion]
Replied On February 10, 2009 05:22 PM UTC

Hi Poly,

I'm using now, so I guess I will need to upgrade first unless you see any other options. By the way, is it an easy thing to do or there are iny backward incopatibilities between versions?


Poly J [Syncfusion]
Replied On February 20, 2009 12:39 PM UTC

Hi Eugene,

Sorry for very long delay in providing an update for you. There will not be any backward compatibility issues between version 6.1 and latest released version 7.1. The latest version includes more features and fixes and I would recommend you to upgrade to the latest version.

Unfortunately am not able to reproduce the issue which you have reported with the stack trace. Can you update me more details on this issue? Are you handling dock control closing /closed events or disposing the dock enabled controls while closing the dock window. Please let me know more details regarding this for providing a solution for this.


Le Van Minh
Replied On August 20, 2009 07:26 AM UTC

I have the same problem. I use Syncfusion DockableWorkspace in Smart Client Software Factory project, the exception appears when the Close method of the Workspace is called to close smartparts.


Le Van Minh
Replied On August 20, 2009 07:52 AM UTC

You can reproduce the problem as following. (I am using Syncfusion WinForms

- Open the VSDEMOCAB_2008 solution in Visual Studio (available when download Syncfusion CAB package)
- Run the application
- Close all smartparts you see
- Open View>Task List
- Sometime the Task List smartpart doesn't appear and if it appears, you close the app and you will see the exception.

I also found other bugs with syncfusion the first time I try the components.

Hope it helps,

Mano J [Syncfusion]
Replied On September 14, 2009 11:37 AM UTC

Hi Le,

Thanks for pointing it out. These issues will be fixed in volume 3 refresh release scheduled to be released this month.

If you see any other issues, please create a new Direct-Trac incident and provide details over there.

Let me know if you have any questions.



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