Hello,
We have received several bug reports from the users of our application that utilizes the XamGrid component. The exception callstack was as follows:
System.NullReferenceException: Object reference not set to an instance of an object. at Infragistics.AutomationPeers.XamGridAutomationPeer.GetChildrenCore() at System.Windows.Automation.Peers.AutomationPeer.EnsureChildren() at System.Windows.Automation.Peers.AutomationPeer.UpdateChildrenInternal(Int32 invalidateLimit) at System.Windows.Automation.Peers.AutomationPeer.UpdateChildren() at System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() at System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() at System.Windows.ContextLayoutManager.fireAutomationEvents() at System.Windows.ContextLayoutManager.UpdateLayout() at System.Windows.ContextLayoutManager.UpdateLayoutCallback(Object arg) at System.Windows.Media.MediaContext.InvokeOnRenderCallback.DoWork() at System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks() at System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget) at System.Windows.Media.MediaContext.AnimatedRenderMessageHandler(Object resizedCompositionTarget)
I've updated the binaries to the latest service release, but it still occurs from time to time on our users' machines. Hasn't ever happened to any of the developers though. Could you please have a look at why this is happening?
Hello AntonK,
For this issue I updated CAS-88010-RWNWMJ and you can find this case within the support activity page: https://ko.infragistics.com/Membership/MySupport.aspx.
Hello Duane,
We have received about 250 crash reports with this error from our users during the last month. However, we still can't reproduce the error ourselves.
Please provide assistance. Have any other xamGrid users reported this issue?
Best regards,AntonK
This is just a follow up if you have any questions on using the xamGrid control and if you require any further assistance with this thread.
At this point I would need a sample for reproducing the NullReferenceException.
Let me know if you have any questions with this matter. Thank you.
Well, there's a window with two xamGrids on it, bound to an ObservableCollection and ListCollectionView respectively. They're heavily restyled to match our design. Editing and column reordering is disabled. We have also applied a few hacks to work around things which we couldn't disable in any other way:
// HACK #1 // Disable mouse capture to prevent flickering in hover effects // Mouse capturing is required when scrolling (OriginalSource = Thumb)// and column resizing (OriginalSource = HeaderCellControl). Mouse.AddGotMouseCaptureHandler(xamGrid, (sender, args) => { if (args.OriginalSource is XamGrid) Mouse.Capture(null); } ); // HACK #2 // Prevent xamGrid from stealing focus when the source ListCollectionView is refreshed. xamGrid.ActiveCellChanging += (sender, args) => { if (!Keyboard.IsKeyDown(Key.Tab)) args.Cancel = true; };