我有一个ComboBox，由于某些应用程序逻辑，它可能会消失。我的问题是，如果禁用了ComboBox的内容，则几乎看不到它。因此，我想做的是在组合框变色后更改前景色。
我还没有在XAML中找到任何简单的方法来做到这一点。如果有人可以帮助我，我将不胜感激。
干杯。
在UWP中，大多数控件都有自己的控件模板。对于某些有状态的复杂控件，例如ComboBox，如果要修改某个状态的样式，则需要修改其控件模板。
这是完整的组合框样式：
<Style TargetType="ComboBox" x:Key="MyComboBoxStyle">
<Setter Property="Padding" Value="12,5,0,7" />
<Setter Property="MaxDropDownHeight" Value="504" />
<Setter Property="Foreground" Value="{ThemeResource ComboBoxForeground}" />
<Setter Property="Background" Value="{ThemeResource ComboBoxBackground}" />
<Setter Property="BorderBrush" Value="{ThemeResource ComboBoxBorderBrush}" />
<Setter Property="BorderThickness" Value="{ThemeResource ComboBoxBorderThemeThickness}" />
<Setter Property="TabNavigation" Value="Once" />
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
<Setter Property="ScrollViewer.HorizontalScrollMode" Value="Disabled" />
<Setter Property="ScrollViewer.VerticalScrollMode" Value="Auto" />
<Setter Property="ScrollViewer.IsVerticalRailEnabled" Value="True" />
<Setter Property="ScrollViewer.IsDeferredScrollingEnabled" Value="False" />
<Setter Property="ScrollViewer.BringIntoViewOnFocusChange" Value="True" />
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Top" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="UseSystemFocusVisuals" Value="{ThemeResource IsApplicationFocusVisualKindReveal}" />
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<CarouselPanel />
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ComboBox">
<Grid x:Name="LayoutRoot">
<Grid.Resources>
<Storyboard x:Key="OverlayOpeningAnimation">
<DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
<DiscreteDoubleKeyFrame KeyTime="0:0:0" Value="0.0" />
<SplineDoubleKeyFrame KeyTime="0:0:0.383" KeySpline="0.1,0.9 0.2,1.0" Value="1.0" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
<Storyboard x:Key="OverlayClosingAnimation">
<DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
<DiscreteDoubleKeyFrame KeyTime="0:0:0" Value="1.0" />
<SplineDoubleKeyFrame KeyTime="0:0:0.216" KeySpline="0.1,0.9 0.2,1.0" Value="0.0" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</Grid.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBorderBrushPointerOver}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBorderBrushPressed}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBorderBrushDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HeaderContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PlaceholderTextBlock" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{Binding PlaceholderForeground, RelativeSource={RelativeSource TemplatedParent}, TargetNullValue={ThemeResource ComboBoxForegroundDisabled}}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="DropDownGlyph" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxDropDownGlyphForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="FocusStates">
<VisualState x:Name="Focused">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="HighlightBackground"
Storyboard.TargetProperty="Opacity"
To="1"
Duration="0" />
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HighlightBackground" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBackgroundBorderBrushFocused}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundFocused}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PlaceholderTextBlock" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{Binding PlaceholderForeground, RelativeSource={RelativeSource TemplatedParent}, TargetNullValue={ThemeResource ComboBoxForegroundFocused}}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="DropDownGlyph" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxDropDownGlyphForegroundFocused}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="FocusedPressed">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="HighlightBackground"
Storyboard.TargetProperty="Opacity"
To="1"
Duration="0" />
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundFocusedPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PlaceholderTextBlock" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{Binding PlaceholderForeground, RelativeSource={RelativeSource TemplatedParent}, TargetNullValue={ThemeResource ComboBoxPlaceHolderForegroundFocusedPressed}}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="DropDownGlyph" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxDropDownGlyphForegroundFocusedPressed}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unfocused" />
<VisualState x:Name="PointerFocused" />
<VisualState x:Name="FocusedDropDown">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PopupBorder" Storyboard.TargetProperty="Visibility" Duration="0">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="DropDownStates">
<VisualState x:Name="Opened">
<Storyboard>
<SplitOpenThemeAnimation OpenedTargetName="PopupBorder"
ClosedTargetName="ContentPresenter"
OffsetFromCenter="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.DropDownOffset}"
OpenedLength="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.DropDownOpenedHeight}" />
</Storyboard>
</VisualState>
<VisualState x:Name="Closed">
<Storyboard>
<SplitCloseThemeAnimation OpenedTargetName="PopupBorder"
ClosedTargetName="ContentPresenter"
OffsetFromCenter="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.DropDownOffset}"
OpenedLength="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.DropDownOpenedHeight}" />
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="EditableModeStates">
<VisualState x:Name="TextBoxFocused">
<VisualState.Setters>
<Setter Target="DropDownGlyph.Foreground" Value="{ThemeResource ComboBoxEditableDropDownGlyphForeground}" />
<Setter Target="DropDownOverlay.Margin" Value="0,3,2,2" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="TextBoxFocusedOverlayPointerOver">
<VisualState.Setters>
<Setter Target="DropDownGlyph.Foreground" Value="{ThemeResource ComboBoxEditableDropDownGlyphForeground}" />
<Setter Target="DropDownOverlay.Background" Value="{ThemeResource ComboBoxFocusedDropDownBackgroundPointerOver}" />
<Setter Target="DropDownOverlay.Margin" Value="0,3,2,2" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="TextBoxFocusedOverlayPressed">
<VisualState.Setters>
<Setter Target="DropDownGlyph.Foreground" Value="{ThemeResource ComboBoxEditableDropDownGlyphForeground}" />
<Setter Target="DropDownOverlay.Background" Value="{ThemeResource ComboBoxFocusedDropDownBackgroundPointerPressed}" />
<Setter Target="DropDownOverlay.Margin" Value="0,3,2,2" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="TextBoxOverlayPointerOver">
<VisualState.Setters>
<Setter Target="DropDownOverlay.Background" Value="{ThemeResource ComboBoxDropDownBackgroundPointerOver}" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="TextBoxOverlayPressed">
<VisualState.Setters>
<Setter Target="DropDownOverlay.Background" Value="{ThemeResource ComboBoxDropDownBackgroundPointerPressed}" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="TextBoxUnfocused" />
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="32" />
</Grid.ColumnDefinitions>
<ContentPresenter x:Name="HeaderContentPresenter"
Grid.Row="0"
Grid.Column="0"
Grid.ColumnSpan="2"
Content="{TemplateBinding Header}"
ContentTemplate="{TemplateBinding HeaderTemplate}"
FlowDirection="{TemplateBinding FlowDirection}"
FontWeight="{ThemeResource ComboBoxHeaderThemeFontWeight}"
Margin="{ThemeResource ComboBoxTopHeaderMargin}"
TextWrapping="Wrap"
VerticalAlignment="Top"
Visibility="Collapsed"
x:DeferLoadStrategy="Lazy" />
<Border x:Name="Background"
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
CornerRadius="{TemplateBinding CornerRadius}"
Control.IsTemplateFocusTarget="True"
MinWidth="{ThemeResource ComboBoxThemeMinWidth}" />
<Border x:Name="HighlightBackground"
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
Background="{ThemeResource ComboBoxBackgroundUnfocused}"
BorderBrush="{ThemeResource ComboBoxBackgroundBorderBrushUnfocused}"
BorderThickness="{TemplateBinding BorderThickness}"
CornerRadius="{TemplateBinding CornerRadius}"
Opacity="0" />
<ContentPresenter x:Name="ContentPresenter"
Grid.Row="1"
Grid.Column="0"
Margin="{TemplateBinding Padding}"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<TextBlock x:Name="PlaceholderTextBlock"
Text="{TemplateBinding PlaceholderText}"
Foreground="{Binding PlaceholderForeground, RelativeSource={RelativeSource TemplatedParent}, TargetNullValue={ThemeResource ComboBoxPlaceHolderForeground}}" />
</ContentPresenter>
<TextBox x:Name="EditableText"
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
Style="{StaticResource ComboBoxTextBoxStyle}"
Margin="0,0,0,0"
Padding="10,3,30,5"
BorderBrush="Transparent"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
PlaceholderText="{TemplateBinding PlaceholderText}"
Foreground="{Binding PlaceholderForeground, RelativeSource={RelativeSource TemplatedParent}, TargetNullValue={ThemeResource ComboBoxPlaceHolderForeground}}"
Text="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Text, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
Visibility="Collapsed"
Header="{TemplateBinding Header}"
AutomationProperties.Name="{TemplateBinding AutomationProperties.Name}"
x:Load="False"/>
<Border x:Name="DropDownOverlay"
Grid.Row="1"
Grid.Column="1"
Background="Transparent"
Margin="0,2,2,2"
Visibility="Collapsed"
Width="30"
HorizontalAlignment="Right"
x:Load="False"/>
<FontIcon x:Name="DropDownGlyph"
Grid.Row="1"
Grid.Column="1"
IsHitTestVisible="False"
Margin="0,10,10,10"
Foreground="{ThemeResource ComboBoxDropDownGlyphForeground}"
FontFamily="{ThemeResource SymbolThemeFontFamily}"
FontSize="12"
Glyph=""
HorizontalAlignment="Right"
VerticalAlignment="Center"
AutomationProperties.AccessibilityView="Raw" />
<ContentPresenter x:Name="DescriptionPresenter"
Grid.Row="2"
Grid.Column="0"
Grid.ColumnSpan="2"
Foreground="{ThemeResource SystemControlDescriptionTextForegroundBrush}"
Content="{TemplateBinding Description}"
x:Load="False"/>
<Popup x:Name="Popup">
<Border x:Name="PopupBorder"
Background="{ThemeResource ComboBoxDropDownBackground}"
BorderBrush="{ThemeResource ComboBoxDropDownBorderBrush}"
BorderThickness="{ThemeResource ComboBoxDropdownBorderThickness}"
Margin="0,-1,0,-1"
Padding="{ThemeResource ComboBoxDropdownBorderPadding}"
HorizontalAlignment="Stretch">
<ScrollViewer x:Name="ScrollViewer"
Foreground="{ThemeResource ComboBoxDropDownForeground}"
MinWidth="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.DropDownContentMinWidth}"
VerticalSnapPointsType="OptionalSingle"
VerticalSnapPointsAlignment="Near"
HorizontalScrollMode="{TemplateBinding ScrollViewer.HorizontalScrollMode}"
HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}"
VerticalScrollMode="{TemplateBinding ScrollViewer.VerticalScrollMode}"
VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}"
IsHorizontalRailEnabled="{TemplateBinding ScrollViewer.IsHorizontalRailEnabled}"
IsVerticalRailEnabled="{TemplateBinding ScrollViewer.IsVerticalRailEnabled}"
IsDeferredScrollingEnabled="{TemplateBinding ScrollViewer.IsDeferredScrollingEnabled}"
BringIntoViewOnFocusChange="{TemplateBinding ScrollViewer.BringIntoViewOnFocusChange}"
ZoomMode="Disabled"
AutomationProperties.AccessibilityView="Raw">
<ItemsPresenter Margin="{ThemeResource ComboBoxDropdownContentMargin}" />
</ScrollViewer>
</Border>
</Popup>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
通过查询关键字Disabled，我们可以找到相应的状态：
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxBorderBrushDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="HeaderContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PlaceholderTextBlock" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{Binding PlaceholderForeground, RelativeSource={RelativeSource TemplatedParent}, TargetNullValue={ThemeResource ComboBoxForegroundDisabled}}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="DropDownGlyph" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxDropDownGlyphForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
您需要修改的全部在这里：
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ComboBoxForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
将值更改为所需的颜色。
如何使用
您可以在Page.Resources标记或Application.Resources标记中放置此组合框样式。
在所需的组合框上添加以下代码：
<ComboBox IsEnabled="False" Style="{StaticResource MyComboBox}">
<!--combo box items-->
</ComboBox>
此外，控件的样式代码将随系统版本而变化。以上样式中的某些属性仅在1809及更高版本的系统版本中可用。所有控件样式都存储在generic.xaml文件中，您可以随意单击XAML中的系统资源引用，然后按F12跳到该文件。
谢谢。