I have been experiencing this error {"Cross-thread operation not valid: Control '' accessed from a thread other than the thread it was created on."} while running my program and I have no clue how/where it throws this exception. I have looked into MSDN: http://msdn.microsoft.com/en-us/library/ms171728(vs.80).aspx and tried to fix the problem with using the Invoke method as described. But I still experience this error from time to time.

The stack trace shows the following:

at System.Windows.Forms.Control.get_Handle()

   at System.Windows.Forms.Control.DestroyHandle()

   at System.Windows.Forms.Control.Dispose(Boolean disposing)

   at Xceed.Editors.WinTextBox.Dispose(Boolean disposing)

   at Xceed.Editors.WinNumericTextBox.Dispose(Boolean disposing)

   at System.ComponentModel.Component.Dispose()

   at Xceed.Grid.Editors.CellEditorManager.Dispose(Boolean disposing)

   at Xceed.Grid.Editors.CellEditorManager.Dispose()

   at Xceed.Grid.Column.DisposeCachedManagerNotFromManagerList(IDisposable manager)

   at Xceed.Grid.Column.Finalize()

Any help would be much appreciated! Thanks.

 

Well, there is no doubt that some UI is being access from a thread different from the thread on which the UI is running.

 In Visual Studio, you can open the Threads window (go to Debug -> Windows -> Threads, at runtime when debugging), which will permit you to see on which thread the different calls to your methods/events are made, and it should help you find out where and when you need to call Invoke, so the calls are redirected on the UI thread.

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André
Software Developer and Tech Support
Xceed Software Inc.

I tried commenting out all other threads in my program and re-run it. I still got the error. It seems to me that the error would be thrown if I open a form (which contains a grid and some buttons) and close the form (by clicking a button on the form) and doing this repeatedly for several times. It is really strange that a cross-thread operation could happen. From the stack trace, it shows something about disposing a grid element. I wonder what the stack trace tells about. Also, any help regarding this cross-thread operation error would be much appreciated. I really have no clue how to fix/debug it further. Thanks.

System.InvalidOperationException was unhandled

  Message="Cross-thread operation not valid: Control '' accessed from a thread other than the thread it was created on."

  Source="System.Windows.Forms"

  StackTrace:

       at System.Windows.Forms.Control.get_Handle()

       at System.Windows.Forms.Control.DestroyHandle()

       at System.Windows.Forms.Control.Dispose(Boolean disposing)

       at Xceed.Editors.WinTextBox.Dispose(Boolean disposing)

       at Xceed.Editors.WinNumericTextBox.Dispose(Boolean disposing)

       at System.ComponentModel.Component.Dispose()

       at Xceed.Grid.Editors.CellEditorManager.Dispose(Boolean disposing)

       at Xceed.Grid.Editors.CellEditorManager.Dispose()

       at Xceed.Grid.Column.DisposeCachedManagerNotFromManagerList(IDisposable manager)

       at Xceed.Grid.Column.Finalize()

 

The text appeared hard to read. I re-posted the stack trace as below:

 

 

System.InvalidOperationException was unhandled

  Message="Cross-thread operation not valid: Control '' accessed from a thread other than the thread it was created on."

  Source="System.Windows.Forms"

  StackTrace:

       at System.Windows.Forms.Control.get_Handle()

       at System.Windows.Forms.Control.DestroyHandle()

       at System.Windows.Forms.Control.Dispose(Boolean disposing)

       at Xceed.Editors.WinTextBox.Dispose(Boolean disposing)

       at Xceed.Editors.WinNumericTextBox.Dispose(Boolean disposing)

       at System.ComponentModel.Component.Dispose()

       at Xceed.Grid.Editors.CellEditorManager.Dispose(Boolean disposing)

       at Xceed.Grid.Editors.CellEditorManager.Dispose()

       at Xceed.Grid.Column.DisposeCachedManagerNotFromManagerList(IDisposable manager)

       at Xceed.Grid.Column.Finalize()

Have you been able to solve this problem? I am getting the same exception, and it also seems to happen under the same circumstances (open and close a Form containing a grid).

I only started getting this exception when I upgraded from Xceed Grid version 2.5 to version 3.7. Before this upgrade, the application in question has been used for several months.

Working with a customer on this, we may have found a problem, but since we do not reproduce it here, it is a bit difficult to be sure.  There may be a workaround for the issue, but we did not test it on our side.  However, it worked for the customer I mentioned.

Before closing the form containing the grid, set the CellEditorManager to null on the columns on which you have NOT set a CellEditorManager, and then call ResetCellEditorManager(). This way, the DEFAULT editor should be correctly released before the GC tries to clean it up, and it may prevent the exception.  If you delete a column without closing the grid, you can do the same, as you would likely have the same exception if you don't.

e.g.:

gridControl1.Columns[ "column1" ].CellEditorManager = null;

gridControl1.Columns[ "column1" ].ResetCellEditorManager();

 

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André
Software Developer and Tech Support
Xceed Software Inc.

Thanks André,

This work-around works for me.

Clarification

To prevent the "Cross-thread operation not valid: Control"  problem do the following:

set

.CellEditorManager = null;
.ResetCellEditorManager();

on the columns that are using the default editors.

For example:

    Dim column As Column

    For Each column In GridControl1.Columns
      column.CellEditorManager = Nothing
      column.ResetCellEditorManager()
    Next
 

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Xceed - Software Developer and Technical Support

in form load write  Windows.Forms.Control.CheckForIllegalCrossThreadCalls = False
hopely u will naver face this problem again...

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Muhammad Ismail Khan
SoftWare Developer
Micro Logix (Pvt) Ltd.
Cell No +92 334 5119655
Email : ismailmarwat@gmail.com

The problem is not at Form_Load, but when the form is closed, and comes from the Garbage Collector (GC), thus CheckForIllegalCrossThreadCalls will not help in this situation.

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André
Software Developer and Tech Support
Xceed Software Inc.

Do we have an eta on when a patch will be released for this.   This is causing us some "issues" as we use grids on a lot of screens.  

 

I tried creating decendant grid destructor; but apparently it isn't being called before this problem occurs(???), meaning I have to change a lot of screens to add code to try and fix this.

 Nathan.

A fix for this will be available in our next service release, which should come out sometime before the end of September.

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André
Software Developer and Tech Support
Xceed Software Inc.