WPF: Styles not applied

i have a setup like

<ribbon:RibbonGallery>
    <ribbon:RibbonGallery.Resources>
        <Style TargetType="ribbon:RibbonGalleryItem">
            <Setter Property="Width" Value="24" />
            <Setter Property="Padding" Value="0" />
        </Style>
        <Style TargetType="Rectangle">
            <Setter Property="Width" Value="16" />
            <Setter Property="Height" Value="16" />
        </Style>
    </ribbon:RibbonGallery.Resources>

    </ribbon:RibbonGalleryCategory>
    <ribbon:RibbonGalleryCategory x:Name="themeColors" Header="Theme Colors" MinColumnCount="10" MaxColumnCount="10">
        <ribbon:RibbonGalleryCategory.ItemTemplate>
            <DataTemplate>
                <StackPanel Orientation="Horizontal" >
                    <开发者_JS百科Rectangle Fill="{Binding}" />
                </StackPanel>
            </DataTemplate>
        </ribbon:RibbonGalleryCategory.ItemTemplate>
    </ribbon:RibbonGalleryCategory>
</ribbon:RibbonGallery>

my width and height are not applied to the rectangles. i wondering whats wrong

You need to give your style a Key and then reference that key in your code:

    <Style x:Key="RectStyle">
        <Setter Property="Width" Value="16" />
        <Setter Property="Height" Value="16" />
    </Style>

Then:

            <StackPanel Orientation="Horizontal" >
                <Rectangle Fill="{Binding}" Style="{StaticResource RectStyle}" />
            </StackPanel>

To get the style to apply to all elements of a type you need to define it like this:

<Style TargetType="{x:Type Rectangle}">

Use the former if you want to have several styles for an element and choose which one you want to apply.

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