Theme Resources to define gradient stop color UWP - binding

Question

I am creating UWP application.I have few LinearGradientBrushes, where the color is set directly in the LinearGradientBrush reference as GradientStops. However, I want to have a predefined set of colors defined in the resource distionary that I can use a a reference for each GradientStop, so that changing the color scheme for the application is a matter of changing the values of the SolidColorBrushes:
<!--Resource Dictionary -->
<ResourceDictionary.ThemeDictionaries>
<ResourceDictionary x:Key="Default">
<SolidColorBrush x:Key="stop1" Color="#FF5A5A5A"/>
<SolidColorBrush x:Key="stop2" Color="#FF222222"/>
</ResourceDictionary>
<ResourceDictionary x:Key="Dark">
<SolidColorBrush x:Key="stop1" Color="Black"/>
<SolidColorBrush x:Key="stop2" Color="White"/>
</ResourceDictionary>
<ResourceDictionary x:Key="HighContrast">
<SolidColorBrush x:Key="stop1" Color="Black"/>
<SolidColorBrush x:Key="stop2" Color="White"/>
</ResourceDictionary>
</ResourceDictionary.ThemeDictionaries>
<!-- control Template-->
<LinearGradientBrush x:Key="gradient">
<GradientStop Color="{Binding Source={Themeresource stop1},Path=Color}" Offset="0"/>
<GradientStop Color="{Binding Source={Themeresource stop2},Path=Color}" Offset="1"/>
</LinearGradientBrush>
Its Giving error that nam/key stop1 is not Found

Answer 1

The problem is stop1 is static resource but not Themeresource . So, we need edit binding source as StaticResource.
<LinearGradientBrush x:Key="gradient">
<GradientStop Color="{Binding Source={StaticResource stop1},Path=Color}" Offset="0"/>
<GradientStop Color="{Binding Source={StaticResource stop2},Path=Color}" Offset="1"/>
</LinearGradientBrush>
Update
For the testing, if we place above in ResourceDictionary, it will work.
<Page.Resources>
<ResourceDictionary>
<ResourceDictionary.ThemeDictionaries>
<ResourceDictionary x:Key="Default">
<SolidColorBrush x:Key="stop1" Color="#FF5A5A5A"/>
<SolidColorBrush x:Key="stop2" Color="#FF222222"/>
</ResourceDictionary>
<ResourceDictionary x:Key="Dark">
<SolidColorBrush x:Key="stop1" Color="Black"/>
<SolidColorBrush x:Key="stop2" Color="White"/>
</ResourceDictionary>
<ResourceDictionary x:Key="HighContrast">
<SolidColorBrush x:Key="stop1" Color="Black"/>
<SolidColorBrush x:Key="stop2" Color="White"/>
</ResourceDictionary>
</ResourceDictionary.ThemeDictionaries>
<!-- control Template-->
<LinearGradientBrush x:Key="gradient">
<GradientStop Color="{Binding Source={ThemeResource stop1},Path=Color}" Offset="0"/>
<GradientStop Color="{Binding Source={ThemeResource stop2},Path=Color}" Offset="1"/>
</LinearGradientBrush>
</ResourceDictionary>
</Page.Resources>

Answer 2

The above problem can be solved by using binding
public LinearGradientBrush GradientBrush
{
get { return _GradientBrush; }
set
{
_GradientBrush = value;
RaisePropertyChanged("GradientBrush");
}
}
GradientBrush = GetGradientBrush();
public static LinearGradientBrush GetGradientBrush()
{
var grColor1 = ((SolidColorBrush)Application.Current.Resources["stop1"]).Color;
var grColor2 = ((SolidColorBrush)Application.Current.Resources["stop2"]).Color;
LinearGradientBrush lgBrush = new LinearGradientBrush();
lgBrush.GradientStops.Add(new GradientStop() { Color = grColor1, Offset = 0.1 });
lgBrush.GradientStops.Add(new GradientStop() { Color = grColor2, Offset = 0.9 });
lgBrush.StartPoint = new Point(0, 1);
lgBrush.EndPoint = new Point(1, 0);
return lgBrush;
}
<Grid Background="{Binding GradientBrush}" >