Question

Well i have a application that is black and white and i need a function to lower the brightness how can i do this? all the white comes from a SolidColorBrush that is saved in a ResourceDictionary(Application.xaml), my current solution is to put a empty window that is back with 80% opacity over it but this does not allow me to use the underlying window..

Answer 1

If all your UI elements are using the same Brush, why not just modify the Brush to reduce the brightness? For example:

public void ReduceBrightness() {     var brush = Application.Resources('Brush') as SolidColorBrush;     var color = brush.Color;     color.R -= 10;     color.G -= 10;     color.B -= 10;     brush.Color = color; } 

Edit after your comment on the Brush being frozen:

If you’re using one of the built-in brushes (via the Brushes class) then it will be frozen. Instead of using one of them, declare your own Brush without freezing it:

<SolidColorBrush x:Key='Brush'>White</SolidColorBrush> 

Edit after Robert’s comment on Application-level resources:

Robert is right. Resources added at the Application level are automatically frozen if they are freezable. Even if you explicitly ask for them not to be frozen:

<SolidColorBrush x:Key='ForegroundBrush' PresentationOptions:Freeze='False' Color='#000000'/> 

There are two ways around this that I can see:

1. As Robert suggested, put the resource at a lower level in the resource tree. For example, in a Window‘s Resources collection. This makes it harder to share though.
2. Put the resource in a wrapper that is not freezable.

As an example of #2 consider the following.

App.xaml:

<Application.Resources>     <FrameworkElement x:Key='ForegroundBrushContainer'>         <FrameworkElement.Tag>             <SolidColorBrush PresentationOptions:Freeze='False' Color='#000000'/>         </FrameworkElement.Tag>     </FrameworkElement> </Application.Resources> 

Window1.xaml:

<StackPanel>     <Label Foreground='{Binding Tag, Source={StaticResource ForegroundBrushContainer}}'>Here is some text in the foreground color.</Label>     <Button x:Name='_button'>Dim</Button> </StackPanel> 

Window1.xaml.cs:

public partial class Window1 : Window {     public Window1()     {         InitializeComponent();         _button.Click += _button_Click;     }      private void _button_Click(object sender, RoutedEventArgs e)     {         var brush = (FindResource('ForegroundBrushContainer') as FrameworkElement).Tag as SolidColorBrush;         var color = brush.Color;         color.R -= 10;         color.G -= 10;         color.B -= 10;         brush.Color = color;     } } 

It’s not as pretty, but it’s the best I can come up with right now.