Semi.Avalonia/src/Semi.Avalonia/Controls/DropDownButton.axaml

<ResourceDictionary
    xmlns="https://github.com/avaloniaui"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:CompileBindings="True">
    <!--  Add Resources Here  -->
    <ControlTheme x:Key="{x:Type DropDownButton}" TargetType="DropDownButton">
        <Setter Property="Background" Value="{DynamicResource ButtonDefaultBackground}" />
        <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultPrimaryForeground}" />
        <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultBorderBrush}" />
        <Setter Property="CornerRadius" Value="{DynamicResource ButtonCornerRadius}" />
        <Setter Property="BorderThickness" Value="{DynamicResource ButtonBorderThickness}" />
        <Setter Property="Padding" Value="{DynamicResource ButtonDefaultPadding}" />
        <Setter Property="RenderTransform" Value="none" />
        <Setter Property="HorizontalAlignment" Value="Center" />
        <Setter Property="VerticalAlignment" Value="Center" />
        <Setter Property="FontSize" Value="{DynamicResource ButtonDefaultFontSize}" />
        <Setter Property="FontWeight" Value="{DynamicResource ButtonDefaultFontWeight}" />
        <Setter Property="HorizontalContentAlignment" Value="Center" />
        <Setter Property="VerticalContentAlignment" Value="Center" />
        <Setter Property="BackgroundSizing" Value="OuterBorderEdge" />
        <Setter Property="MinHeight" Value="{DynamicResource ButtonDefaultHeight}" />
        <Setter Property="Cursor" Value="Hand" />
        <Setter Property="Template">
            <ControlTemplate TargetType="DropDownButton">
                <Border
                    x:Name="RootBorder"
                    HorizontalAlignment="Stretch"
                    VerticalAlignment="Stretch"
                    BackgroundSizing="{TemplateBinding BackgroundSizing}"
                    BorderThickness="{TemplateBinding BorderThickness}"
                    ClipToBounds="True"
                    CornerRadius="{TemplateBinding CornerRadius}">
                    <Grid x:Name="InnerGrid" ColumnDefinitions="*,Auto">
                        <ContentPresenter
                            x:Name="PART_ContentPresenter"
                            Grid.Column="0"
                            Padding="{TemplateBinding Padding}"
                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                            VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                            Content="{TemplateBinding Content}"
                            ContentTemplate="{TemplateBinding ContentTemplate}"
                            Foreground="{TemplateBinding Foreground}"
                            RecognizesAccessKey="True" />
                        <PathIcon
                            x:Name="DropDownGlyph"
                            Grid.Column="1"
                            Width="12"
                            Height="12"
                            Margin="0,0,8,0"
                            HorizontalAlignment="Right"
                            VerticalAlignment="Center"
                            Data="{DynamicResource DropDownButtonIconGlyph}"
                            Foreground="{TemplateBinding Foreground}"
                            IsHitTestVisible="False"
                            UseLayoutRounding="False" />
                    </Grid>
                </Border>
            </ControlTemplate>
        </Setter>

        <Style Selector="^:pressed">
            <Setter Property="RenderTransform" Value="scale(0.98)" />
        </Style>

        <Style Selector="^ /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{TemplateBinding BorderBrush}" />
            <Setter Property="Background" Value="{TemplateBinding Background}" />
        </Style>

        <Style Selector="^:pointerover /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultPointeroverBorderBrush}" />
            <Setter Property="Background" Value="{DynamicResource ButtonDefaultPointeroverBackground}" />
        </Style>

        <Style Selector="^:pressed /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultPressedBorderBrush}" />
            <Setter Property="Background" Value="{DynamicResource ButtonDefaultPressedBackground}" />
        </Style>

        <Style Selector="^.Primary">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultPrimaryForeground}" />
        </Style>
        <Style Selector="^.Secondary">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultSecondaryForeground}" />
        </Style>
        <Style Selector="^.Tertiary">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultTertiaryForeground}" />
        </Style>
        <Style Selector="^.Success">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultSuccessForeground}" />
        </Style>
        <Style Selector="^.Warning">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultWarningForeground}" />
        </Style>
        <Style Selector="^.Danger">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultDangerForeground}" />
        </Style>

        <Style Selector="^:pointerover /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultPointeroverBorderBrush}" />
            <Setter Property="Background" Value="{DynamicResource ButtonDefaultPointeroverBackground}" />
        </Style>

        <Style Selector="^:pressed /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultPressedBorderBrush}" />
            <Setter Property="Background" Value="{DynamicResource ButtonDefaultPressedBackground}" />
        </Style>
        <Style Selector="^:disabled">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultDisabledForeground}" />
        </Style>
        <Style Selector="^:disabled /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultDisabledBorderBrush}" />
        </Style>

        <Style Selector="^.Large">
            <Setter Property="Padding" Value="{DynamicResource ButtonLargePadding}" />
            <Setter Property="MinHeight" Value="{DynamicResource ButtonLargeHeight}" />
        </Style>
        <Style Selector="^.Small">
            <Setter Property="Padding" Value="{DynamicResource ButtonSmallPadding}" />
            <Setter Property="MinHeight" Value="{DynamicResource ButtonSmallHeight}" />
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="SolidDropDownButton"
        BasedOn="{StaticResource {x:Type DropDownButton}}"
        TargetType="DropDownButton">
        <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
        <Style Selector="^ /template/ Border#RootBorder">
            <Setter Property="Background" Value="{DynamicResource ButtonSolidPrimaryBackground}" />
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidPrimaryBorderBrush}" />
        </Style>
        <Style Selector="^:pointerover /template/ Border#RootBorder">
            <Setter Property="Background" Value="{DynamicResource ButtonSolidPrimaryPointeroverBackground}" />
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidPrimaryPointeroverBorderBrush}" />
        </Style>
        <Style Selector="^:pressed /template/ Border#RootBorder">
            <Setter Property="Background" Value="{DynamicResource ButtonSolidPrimaryPressedBackground}" />
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidPrimaryPressedBorderBrush}" />
        </Style>
        <Style Selector="^.Primary">
            <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
            <Style Selector="^ /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidPrimaryBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidPrimaryBorderBrush}" />
            </Style>
            <Style Selector="^:pointerover /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidPrimaryPointeroverBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidPrimaryPointeroverBorderBrush}" />
            </Style>
            <Style Selector="^:pressed /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidPrimaryPressedBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidPrimaryPressedBorderBrush}" />
            </Style>
        </Style>
        <Style Selector="^.Secondary">
            <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
            <Style Selector="^ /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidSecondaryBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidSecondaryBorderBrush}" />
            </Style>
            <Style Selector="^:pointerover /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidSecondaryPointeroverBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidSecondaryPointeroverBorderBrush}" />
            </Style>
            <Style Selector="^:pressed /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidSecondaryPressedBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidSecondaryPressedBorderBrush}" />
            </Style>
        </Style>
        <Style Selector="^.Tertiary">
            <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
            <Style Selector="^ /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidTertiaryBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidTertiaryBorderBrush}" />
            </Style>
            <Style Selector="^:pointerover /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidTertiaryPointeroverBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidTertiaryPointeroverBorderBrush}" />
            </Style>
            <Style Selector="^:pressed /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidTertiaryPressedBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidTertiaryPressedBorderBrush}" />
            </Style>
        </Style>
        <Style Selector="^.Success">
            <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
            <Style Selector="^ /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidSuccessBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidSuccessBorderBrush}" />
            </Style>
            <Style Selector="^:pointerover /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidSuccessPointeroverBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidSuccessPointeroverBorderBrush}" />
            </Style>
            <Style Selector="^:pressed /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidSuccessPressedBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidSuccessPressedBorderBrush}" />
            </Style>
        </Style>
        <Style Selector="^.Warning">
            <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
            <Style Selector="^ /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidWarningBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidWarningBorderBrush}" />
            </Style>
            <Style Selector="^:pointerover /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidWarningPointeroverBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidWarningPointeroverBorderBrush}" />
            </Style>
            <Style Selector="^:pressed /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidWarningPressedBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidWarningPressedBorderBrush}" />
            </Style>
        </Style>
        <Style Selector="^.Danger">
            <Setter Property="Foreground" Value="{DynamicResource ButtonSolidForeground}" />
            <Style Selector="^ /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidDangerBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidDangerBorderBrush}" />
            </Style>
            <Style Selector="^:pointerover /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidDangerPointeroverBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidDangerPointeroverBorderBrush}" />
            </Style>
            <Style Selector="^:pressed /template/ Border#RootBorder">
                <Setter Property="Background" Value="{DynamicResource ButtonSolidDangerPressedBackground}" />
                <Setter Property="BorderBrush" Value="{DynamicResource ButtonSolidDangerPressedBorderBrush}" />
            </Style>
        </Style>
        <Style Selector="^:disabled /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonDefaultDisabledBorderBrush}" />
            <Setter Property="Background" Value="{DynamicResource ButtonSolidDisabledBackground}" />
        </Style>
        <Style Selector="^:disabled">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultDisabledForeground}" />
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="OutlineDropDownButton"
        BasedOn="{StaticResource {x:Type DropDownButton}}"
        TargetType="DropDownButton">
        <Style Selector="^ /template/ Border#RootBorder">
            <Setter Property="Background" Value="{DynamicResource ButtonOutlineBackground}" />
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineBorderBrush}" />
        </Style>
        <Style Selector="^:pointerover /template/ Border#RootBorder">
            <Setter Property="Background" Value="{DynamicResource ButtonOutlinePointeroverBackground}" />
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineBorderBrush}" />
        </Style>
        <Style Selector="^:pressed /template/ Border#RootBorder">
            <Setter Property="Background" Value="{DynamicResource ButtonOutlinePressedBackground}" />
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineBorderBrush}" />
        </Style>
        <Style Selector="^.Success /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineSuccessBorderBrush}" />
        </Style>
        <Style Selector="^.Warning /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineWarningBorderBrush}" />
        </Style>
        <Style Selector="^.Danger /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineDangerBorderBrush}" />
        </Style>
        <Style Selector="^:disabled /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="{DynamicResource ButtonOutlineBorderBrush}" />
            <Setter Property="Background" Value="{DynamicResource ButtonOutlineBackground}" />
        </Style>
        <Style Selector="^:disabled">
            <Setter Property="Foreground" Value="{DynamicResource ButtonDefaultDisabledForeground}" />
        </Style>
    </ControlTheme>

    <ControlTheme
        x:Key="BorderlessDropDownButton"
        BasedOn="{StaticResource {x:Type DropDownButton}}"
        TargetType="DropDownButton">
        <Style Selector="^ /template/ Border#RootBorder">
            <Setter Property="Background" Value="Transparent" />
            <Setter Property="BorderBrush" Value="Transparent" />
        </Style>
        <Style Selector="^:disabled /template/ Border#RootBorder">
            <Setter Property="BorderBrush" Value="Transparent" />
            <Setter Property="Background" Value="Transparent" />
        </Style>
    </ControlTheme>
</ResourceDictionary>