Winforms TabControl causing spurious Paint events for UserControl
- by Tom Bushell
For our project, we've written a WinForms UserControl for graphing.
We're seeing some strange behavior when our control is sited in a TabControl - our control continuously fires Paint events, even when there is absolutely no activity by the user.
We only see this in the TabControl. When we site our control in other containers such as Forms or Splitters, Paint is only fired when you'd expect e.g. when the control is first displayed, etc.
Can anyone suggest why this might be happening?
Here's a stack trace from a breakpoint in our control's Paint handler, if that's any help.
OverlordFrontEnd.exe!OverlordFrontEnd.MainForm.graphControl_Paint(object sender = BI_BaseGraphXY.BaseGraphXY}, System.Windows.Forms.PaintEventArgs e = {ClipRectangle = {X=0,Y=0,Width=1031,Height=408}}) Line 422 C#
System.Windows.Forms.dll!System.Windows.Forms.Control.OnPaint(System.Windows.Forms.PaintEventArgs e) + 0x73 bytes
BI_AppCore.dll!BI_BaseGraphXY.BaseGraphXY.OnPaint(System.Windows.Forms.PaintEventArgs e = {ClipRectangle = {X=0,Y=0,Width=1031,Height=408}}) Line 377 + 0xb bytes C#
System.Windows.Forms.dll!System.Windows.Forms.Control.PaintTransparentBackground(System.Windows.Forms.PaintEventArgs e, System.Drawing.Rectangle rectangle, System.Drawing.Region transparentRegion = null) + 0x16c bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.PaintBackground(System.Windows.Forms.PaintEventArgs e = {ClipRectangle = {X=0,Y=0,Width=1029,Height=406}}, System.Drawing.Rectangle rectangle, System.Drawing.Color backColor, System.Drawing.Point scrollOffset) + 0xbc bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.PaintBackground(System.Windows.Forms.PaintEventArgs e, System.Drawing.Rectangle rectangle) + 0x63 bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.OnPaintBackground(System.Windows.Forms.PaintEventArgs pevent) + 0x59 bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.PaintWithErrorHandling(System.Windows.Forms.PaintEventArgs e = {ClipRectangle = {X=0,Y=0,Width=1029,Height=406}}, short layer, bool disposeEventArgs = false) + 0x74 bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.WmPaint(ref System.Windows.Forms.Message m) + 0x1ba bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.WndProc(ref System.Windows.Forms.Message m) + 0x33e bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.ControlNativeWindow.OnMessage(ref System.Windows.Forms.Message m) + 0x10 bytes
System.Windows.Forms.dll!System.Windows.Forms.Control.ControlNativeWindow.WndProc(ref System.Windows.Forms.Message m) + 0x31 bytes
System.Windows.Forms.dll!System.Windows.Forms.NativeWindow.Callback(System.IntPtr hWnd, int msg = 15, System.IntPtr wparam, System.IntPtr lparam) + 0x5a bytes
[Native to Managed Transition]
[Managed to Native Transition]
System.Windows.Forms.dll!System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(int dwComponentID, int reason = -1, int pvLoopData = 0) + 0x24e bytes
System.Windows.Forms.dll!System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(int reason = -1, System.Windows.Forms.ApplicationContext context = {Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.WinFormsAppContext}) + 0x177 bytes
System.Windows.Forms.dll!System.Windows.Forms.Application.ThreadContext.RunMessageLoop(int reason, System.Windows.Forms.ApplicationContext context) + 0x61 bytes
System.Windows.Forms.dll!System.Windows.Forms.Application.Run(System.Windows.Forms.ApplicationContext context) + 0x18 bytes
Microsoft.VisualBasic.dll!Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun() + 0x81 bytes
Microsoft.VisualBasic.dll!Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel() + 0xef bytes
Microsoft.VisualBasic.dll!Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.Run(string[] commandLine) + 0x2c0 bytes
OverlordFrontEnd.exe!OverlordFrontEnd.Program.Main() Line 36 + 0x10 bytes C#
[Native to Managed Transition]
[Managed to Native Transition]
mscorlib.dll!System.AppDomain.ExecuteAssembly(string assemblyFile, System.Security.Policy.Evidence assemblySecurity, string[] args) + 0x3a bytes
Microsoft.VisualStudio.HostingProcess.Utilities.dll!Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly() + 0x2b bytes
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart_Context(object state) + 0x66 bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x6f bytes
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart() + 0x44 bytes