We have an MDI application that uses an UltraTree object to display hierarchical functions to user. About a month ago, we upgraded our Infragistics components to the latest release, 11.2 CLR 4.0, SR 2028.
We're now experiencing a random error, that appears during mouse operations (mouse move, mouse click) on UltraTree, and that is intercepted by OS as an Unhandled exception:
System.ObjectDisposedException: Cannot access a disposed object.Object name: 'ToolTipFormEx'. at System.Windows.Forms.Control.CreateHandle() at System.Windows.Forms.Form.CreateHandle() at Infragistics.Win.ToolTipForm.CreateHandle() at System.Windows.Forms.Control.RecreateHandleCore() at System.Windows.Forms.Form.RecreateHandleCore() at Infragistics.Win.ToolTipFormEx.set_DisplayShadow(Boolean value) at Infragistics.Win.ToolTip.set_DisplayShadow(Boolean value) at Infragistics.Win.UltraWinTree.UltraTree.get_ToolTip() at Infragistics.Win.UltraWinTree.UltraTreeNode.ShowTooltipIfNeeded() at Infragistics.Win.UltraWinTree.UltraTree.OnMouseEnterElement(UIElementEventArgs e) at Infragistics.Win.UltraControlBase.Infragistics.Win.IUltraControl.FireMouseEnterElement(UIElementEventArgs e) at Infragistics.Win.ControlUIElementBase.ElementEntered(UIElement element, Boolean triggerMouseLeavesOnly) at Infragistics.Win.ControlUIElementBase.ProcessMouseMoveHelper(Object sender, mouseEventArgs e) at Infragistics.Win.ControlUIElementBase.ProcessMouseMove(Object sender, MouseEventArgs e) at Infragistics.Win.Utilities.ProcessEvent(Control control, ProcessEvent eventToProcess, EventArgs e) at Infragistics.Win.UltraWinTree.UltraTree.OnMouseMove(MouseEventArgs e) at System.Windows.Forms.Control.WmMouseMove(Message& m) at System.Windows.Forms.Control.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)
Could you please help us to avoid this behaviour? If you need details, please ask.Thanks!
I have not been able to reproduce this issue. Would you be able to post here a sample application that reproduces the issue on your end so that I could test it here? Have you tried the work-around that was suggested here on this forum thread?
Michael,it is difficult to post a sample application, since in both cases the issue is appearing randomly.
I agree with Mike (btw, thank you for your response! :) ) that the problem could be related to 11.2 version, as we never saw it with any previous release.
I also noticed that the problem could be caused by updating the current application's skin (we have a combo that allows the user to change app appearance at run time) and then move the mouse over the tree.
I think we cannot use the solution suggested by Mike in a production environment, because it's a workaround to avoid the error being shown to the user. It doesn't guarantee that the application still remains in a correct state, once the error occurred. As Mike said, sometimes a red X replaces the tree and the application must be restarted.