WPF

<Style x:Key="StyleUDPBaseButton" TargetType="{x:Type Button}" >
    <Style.Triggers>
        <Trigger Property="IsEnabled" Value="false">
            <Setter Property="Opacity" Value="0.40" />
        </Trigger>
    </Style.Triggers>
</Style>

<Style x:Key="ToolbarButtonNewServiceOrder" TargetType="{x:Type Button}"
                BasedOn="{StaticResource StyleToolbarButtonEx}" >
    <Setter Property="ToolTip" Value="Create a new service order" />
    <Setter Property="Template" >
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Button}">
                <Image Source="/CometResources;component/Images/GlassServiceOrder64.png" />
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<Grid Name="gridToolbarObjects" MinHeight="41" MaxHeight="41">
    <Button Name="buttonNewServiceOrder" Style="{DynamicResource ToolbarButtonNewServiceOrder}" />
</Grid>

<Application.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="/CometResources;component/Styles.xaml" />
            <ResourceDictionary Source="/CometResources;component/Buttons.xaml" />
        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>
</Application.Resources>

startIndex cannot be larger than length of string.<br />
Parameter name: startIndex

<ResourceDictionary Source="pack://application:,,,/CometResources;component/Styles.xaml"/>
<ResourceDictionary Source="pack://application:,,,/CometResources;component/Buttons.xaml"/>

Mark Salsbery wrote:

I also saw you used a "StaticResource" in there....depending on where that desired
resource is in your chain of dictionaries, you may need to use DynamicResource.

private static IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
  const WM_QUERYENDSESSION = 0x0011;
  switch (msg)
  {
    case WM_QUERYENDSESSION:
      // The "screen" is fading here - do what you need to do...
      break;
  }
  return IntPtr.Zero;
}

void MyWindow_Loaded(object sender, RoutedEventArgs e)
{
  HwndSource src = HwndSource.FromHwnd(new WindowInteropHelper(this).Handle);
  src.AddHook(new HwndSourceHook(WndProc));
}