Hello :)

Thank you for your input. I apologize for the delay in reply.

I am afraid our project is not yet ready to integrate version 11.2 of the Infragistics solutions and as such it would have been difficult to test for this issue. Currently, we are using version 9.2 (9.2.20092.1003) Especially considering that this error is highly intermittent and tough to pin down.

We are not actively using timers on our own, but rather setting the UltraDesktopAlert.AutoCloseDelay property. I was surprised to find no timer-related code by ourselves. This is what led me to consider it might be an unfortunate happenstance between the UltraDesktopAlert and how we use it. Yet there is only simple code in the DesktopAlertClosing event handler; see below.

If this has been solved in the meantime, I apologize for having taken up so much of your time.

private void OnDesktopAlertClosing(object sender, DesktopAlertClosingEventArgs e)
{
    if (_DetailLinkClicked > 0)
    {
        e.Cancel = true;
    }
}
 

Hello,

I've built a small sample using the provided code, but I was unable to reproduce the issue. I'm not sure what steps I should take to reproduce it. Can you please let me know what the user was doing when this exception occurred?

Please test this sample on your end, and let me know whether you see the exception. If not, we'll have to look at some more code to find the cause.

Hello, and thank you for your intensive search.

Unfortunately I can not offer much detail about this; it is a very, very intermittent event. The project has been going on for years, is still under active development, yet this particular event only happened two or three times (to the extent of my knowledge). That an actual, external user had this happen seems to me like an instance of Murphy's Law.

While this luckily means it is not a critical mishap in our product, it unfortunately also means I am sorry I cannot provide details about the circumstances.

Best regards,

  Cornelius

Hi Cornelius,

I have discussed this issue with our engineers. The team looked into our desktop alert code for the methods listed in the call stack, as well as the code for the UpdateLayered method. Here's the code for UpdateLayered:

private void UpdateLayered()
{
    if (((this.formState[FormStateLayered] != 0) && base.IsHandleCreated) && (this.TopLevel && OSFeature.Feature.IsPresent(OSFeature.LayeredWindows)))
    {
        bool flag;
        Color transparencyKey = this.TransparencyKey;
        if (transparencyKey.IsEmpty)
        {
            flag = UnsafeNativeMethods.SetLayeredWindowAttributes(new HandleRef(this, base.Handle), 0, this.OpacityAsByte, 2);
        }
        else if (this.OpacityAsByte == 0xff)
        {
            flag = UnsafeNativeMethods.SetLayeredWindowAttributes(new HandleRef(this, base.Handle), ColorTranslator.ToWin32(transparencyKey), 0, 1);
        }
        else
        {
            flag = UnsafeNativeMethods.SetLayeredWindowAttributes(new HandleRef(this, base.Handle), ColorTranslator.ToWin32(transparencyKey), this.OpacityAsByte, 3);
       }
        if (!flag)
        {
            throw new Win32Exception();
        }
    }

}

We can see that the exception is most likely thrown due to something that occurred in SetLayeredWindowAttributes. However, without more information, we have no way to know what specifically went wrong - We cannot tell the state of memory, the values of parameters, etc.

If this issue does come up again and you are able to gather more information, please let me know and I will forward it on to our engineers.

Hello! :)

Thank you for your care and effort. I am sorry that I could not provide more information. The code you included will give us pointers what to look for; if this error happenes ever again, I will get back to you with as much detail as we can gather.