NullReferenceException in SystemColorTracker.CleanOutBrokenLinks()

[Brian Ingenito]

Switched focus from one application to one with XPMenus and received the following error:

System.NullReferenceException: Object reference not set to an instance of an object.
at System.Drawing.Internal.SystemColorTracker.CleanOutBrokenLinks()
at System.Drawing.Internal.SystemColorTracker.GarbageCollectList()
at System.Drawing.Internal.SystemColorTracker.Add(ISystemColorTracker obj)
at System.Drawing.Pen..ctor(Color color, Single width)
at Syncfusion.Windows.Forms.Tools.CommandBar.DrawGripper(Graphics gph)
at Syncfusion.Windows.Forms.Tools.CommandBar.DrawDockedForeground(Graphics gph)
at Syncfusion.Windows.Forms.Tools.CommandBar.OnPaint(PaintEventArgs e)
at Syncfusion.Windows.Forms.Tools.XPMenus.CommandBarExt.OnPaint(PaintEventArgs e)
at System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer, Boolean disposeEventArgs)
at System.Windows.Forms.Control.WmPaint(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at Syncfusion.Windows.Forms.Tools.XPMenus.CommandBarExt.WndProc(Message& m)
at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

[Brian Ingenito]

Using 2.1, with default menu style on Windows XP.

>Switched focus from one application to one with XPMenus and received the following error:
>
>System.NullReferenceException: Object reference not set to an instance of an object.
> at System.Drawing.Internal.SystemColorTracker.CleanOutBrokenLinks()
> at System.Drawing.Internal.SystemColorTracker.GarbageCollectList()
> at System.Drawing.Internal.SystemColorTracker.Add(ISystemColorTracker obj)
> at System.Drawing.Pen..ctor(Color color, Single width)
> at Syncfusion.Windows.Forms.Tools.CommandBar.DrawGripper(Graphics gph)
> at Syncfusion.Windows.Forms.Tools.CommandBar.DrawDockedForeground(Graphics gph)
> at Syncfusion.Windows.Forms.Tools.CommandBar.OnPaint(PaintEventArgs e)
> at Syncfusion.Windows.Forms.Tools.XPMenus.CommandBarExt.OnPaint(PaintEventArgs e)
> at System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer, Boolean disposeEventArgs)
> at System.Windows.Forms.Control.WmPaint(Message& m)
> at System.Windows.Forms.Control.WndProc(Message& m)
> at Syncfusion.Windows.Forms.Tools.XPMenus.CommandBarExt.WndProc(Message& m)
> at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
> at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
> at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

[Administrator]

Hi Brian,

Is this a one time problem or have you been able to reproduce it? Some more information or a sample could help me track this down. Thank you for your cooperation in this matter.

Regards,
Gregory Austin
Syncfusion, Inc.

[Brian Ingenito]

I''ve seen this twice while testing, but can''t readily reproduce. Both times resulted in the main menu having a red x over it.

I''ve seen object in use elsewhere errors frequently in paint events. We upgraded from 1.6 to 2.1 to try and eliminate, but with no success. I think they happen more frequently now.

I''ve double and triple checked threading and I''m positive all access to the barmanager is done on the appropriate thread.

>Hi Brian,
>
> Is this a one time problem or have you been able to reproduce it? Some more information or a sample could help me track this down. Thank you for your cooperation in this matter.
>
>Regards,
>Gregory Austin
>Syncfusion, Inc.

[Administrator]

Hi Brian, Please review the following MS Forum post to verify that you''re accessing your Controls correctly from your Threads: Controls / Thread Safe ? If that doesn''t help, could you please provide us with a sample that demonstrates this problem or a stripped down version of your application so that we can attempt to reproduce this problem? Regards, Gregory Austin Syncfusion, Inc.