Hi,

I am using to UltraTabControl 6.3. I want to blink the tab when query executed sucessfully. Here is the code. Exception occurs when control backcolor changes. Due to this red X appears on tabconrol.

  private void BlinkTab()
        {
            try
            {
                if (UltraTab != null)
                {
                    Monitor.Enter(UltraTab);
                    {
                        bool blnIsOriginal = true;

                        while (!UltraTab.Selected && !this.IsDisposed)
                        {
                            try
                            {
                                if (blnIsOriginal)
                                {
                                    UltraTab.Appearance.BackColor = System.Drawing.SystemColors.ActiveCaption;
                                    UltraTab.Appearance.BackColor2 = System.Drawing.SystemColors.GradientInactiveCaption;
                                    blnIsOriginal = false;
                                    Thread.Sleep(500);
                                }
                                else
                                {
                                    blnIsOriginal = true;
                                    UltraTab.Appearance.BackColor = Color.Empty;
                                    UltraTab.Appearance.BackColor2 = Color.Empty;
                                    Thread.Sleep(500);
                                }
                            }
                            catch (Exception ex)
                            {
                                Console.Write("Exception in blinking.");
                            }
                        }
                        UltraTab.Appearance.BackColor = Color.Empty;

                    }
                }
            }
            catch (Exception ex)
            {
                BlinkTab();
            }
            finally
            {
                Monitor.Exit(UltraTab);
            }
        }
        private void BlinkEvent(UltraTab pulUltraTab)
        {
            _mUltraTab = pulUltraTab;
            Thread objThreadBlinkTab = new Thread(new ThreadStart(BlinkTab));
            objThreadBlinkTab.Start();
        }

But when I run the multiple queries and wait for minutes it is giving error object reference is not instance of that object on changing the color backcolor. I am having each tab in seperate object and this function is private.

Here is exception it changes every time

System.NullReferenceException occurred
  Message="Object reference not set to an instance of an object."
  Source="Infragistics2.Win.v6.3"
  StackTrace:
       at Infragistics.Win.UIElement.GetDescendant(Type type, Object[] contexts)
       at Infragistics.Win.UIElement.GetDescendant(Type type, Object context)
       at Infragistics.Win.UltraWinTabs.TabManager.GetUIElement(ITabItem tab)
       at Infragistics.Win.UltraWinTabs.TabManager.DirtyTabItem(ITabItem tab, Boolean invalidate, Boolean dirtyTextMetrics, Boolean dirtyImageMetrics)
       at Infragistics.Win.UltraWinTabControl.UltraTabsCollection.OnSubObjectPropChanged(PropChangeInfo propChangeInfo)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(PropChangeInfo trigger)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(Enum propId, PropChangeInfo trigger)
       at Infragistics.Win.UltraWinTabControl.UltraTab.OnSubObjectPropChanged(PropChangeInfo propChangeInfo)
       at Infragistics.Win.AppearanceHolder.OnSubObjectPropChanged(PropChangeInfo propChange)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(PropChangeInfo trigger)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(Enum propId)
       at Infragistics.Win.AppearanceData.set_BackColor2(Color value)
       at Infragistics.Win.Appearance.set_BackColor2(Color value)
       at Thomson.Financial.Framework.Data.MarketQA.MarketQAClient.BlinkTab() in D:\SVN\Branches\.....\..\Client.cs:line 1273


System.NullReferenceException occurred
  Message="Object reference not set to an instance of an object."
  Source="Infragistics2.Win.UltraWinTabControl.v6.3"
  StackTrace:
       at Infragistics.Win.UltraWinTabControl.UltraTabControlBase.get_StyleResolved()
       at Infragistics.Win.UltraWinTabControl.UltraTabControlBase.TabControlTabProvider.Infragistics.Win.UltraWinTabs.ITabProvider.get_Style()
       at Infragistics.Win.UltraWinTabs.TabManager.get_StyleResolved()
       at Infragistics.Win.UltraWinTabs.TabManager.get_InterTabSpacingResolved()
       at Infragistics.Win.UltraWinTabs.TabManager.InitializeFirstDisplayedTabItem(ITabItem tab, ScrollType scrollType, Int32 scrollIncrement, Boolean fireScrollEvents)
       at Infragistics.Win.UltraWinTabs.TabManager.VerifyFirstDisplayedTabItem()
       at Infragistics.Win.UltraWinTabs.TabManager.get_FirstDisplayedTabItem()
       at Infragistics.Win.UltraWinTabs.TabManager.IsTabItemInView(ITabItem tab, Boolean excludePartiallyInView)
       at Infragistics.Win.UltraWinTabs.TabManager.GetUIElement(ITabItem tab)
       at Infragistics.Win.UltraWinTabs.TabManager.DirtyTabItem(ITabItem tab, Boolean invalidate, Boolean dirtyTextMetrics, Boolean dirtyImageMetrics)
       at Infragistics.Win.UltraWinTabControl.UltraTabsCollection.OnSubObjectPropChanged(PropChangeInfo propChangeInfo)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(PropChangeInfo trigger)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(Enum propId, PropChangeInfo trigger)
       at Infragistics.Win.UltraWinTabControl.UltraTab.OnSubObjectPropChanged(PropChangeInfo propChangeInfo)
       at Infragistics.Win.AppearanceHolder.OnSubObjectPropChanged(PropChangeInfo propChange)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(PropChangeInfo trigger)
       at Infragistics.Shared.SubObjectBase.NotifyPropChange(Enum propId)
       at Infragistics.Win.AppearanceData.set_BackColor2(Color value)
       at Infragistics.Win.Appearance.set_BackColor2(Color value)
       at Thomson.Financial.Framework.Data.MarketQA.MarketQAClient.BlinkTab() in D:\SVN\Branches\.....\..\Client.cs: line 1273