Como usar cores do sistema em um gradiente
Para usar uma cor do sistema em um gradiente, use as propriedades estáticas *SystemColor*Color e *SystemColor*<ColorKey da SystemColors classe para obter uma referência à cor, onde <SystemColor>>> é o nome da cor do sistema desejada.< Use as propriedades *SystemColor>*<ColorKey quando quiser criar uma referência dinâmica que seja atualizada automaticamente conforme o tema do sistema for alterado. Caso contrário, use as propriedades *SystemColor*<Color>.
Exemplo
O exemplo a seguir usa recursos de cores dinâmicas do sistema para criar um gradiente.
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
WindowTitle="Dynamic System Colors Example" Background="White">
<StackPanel Margin="20">
<!-- Uses dynamic references to system colors to set
the colors of gradient stops.
If these system colors change while this application
is running, the gradient will be updated
automatically. -->
<Button Content="Hello, World!">
<Button.Background>
<LinearGradientBrush>
<LinearGradientBrush.GradientStops>
<GradientStop Offset="0.0"
Color="{DynamicResource {x:Static SystemColors.DesktopColorKey}}" />
<GradientStop Offset="1.0"
Color="{DynamicResource {x:Static SystemColors.ControlLightLightColorKey}}" />
</LinearGradientBrush.GradientStops>
</LinearGradientBrush>
</Button.Background>
</Button>
</StackPanel>
</Page>
O próximo exemplo usa recursos de cores estáticas do sistema para criar um gradiente.
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
WindowTitle="Static System Colors Example" Background="White">
<StackPanel Margin="20">
<!-- Uses static references to system colors to set
the colors of gradient stops.
If these system colors change while this application
is running, this button will not be updated until
the page is loaded again. -->
<Button Content="Hello, World!">
<Button.Background>
<LinearGradientBrush>
<LinearGradientBrush.GradientStops>
<GradientStop Offset="0.0"
Color="{x:Static SystemColors.DesktopColor}" />
<GradientStop Offset="1.0"
Color="{x:Static SystemColors.ControlLightLightColor}" />
</LinearGradientBrush.GradientStops>
</LinearGradientBrush>
</Button.Background>
</Button>
</StackPanel>
</Page>
Confira também
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