Question

问候

我对WPF中的组合框有疑问，让我勾勒出目前的情况，我有：

<ComboBox IsEditable="False" Height="23" HorizontalAlignment="Left" Margin="8,112,0,0" Name="comboBox1" VerticalAlignment="Top" Width="140" Background="Transparent">
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Red.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Blue.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Teal.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Purple.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Yellow.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Orange.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Green.png" Width="122" />
    <Image Source="pack://application:,,,/Images/Style/Player/Static/Pink.png" Width="122" />
</ComboBox>

简而言之，ComboBox中有一些图像作为ComboboxItem。我怎么能这样做，以便我有一个大的背景图像（组合框中扩展框的大小）所有这些图像而不是1个背景图像PER ComboboxItem。 ComboboxItem中的每个图像都具有透明背景，因此背景图像应该是可见的。

感谢您的阅读和可能的建议。

Answer 1

您必须为组合框编写自己的样式，并以此样式更改模板部分在本文http://msdn.microsoft.com/en-us/library/ms752094.aspx中，您可以找到如何为组合框编写自己的样式要更改弹出窗口的背景，您必须以此样式更改PART_Popup。

Answer 2

改变组合框的背景弹出并不像听起来那么容易（据我所知），就像Korin-Marek K.所述。您必须重新模板化ComboBox并在弹出窗口中设置边框的背景。幸运的是，访问Blend并不是那么难。您必须添加对PresentationFramework.Aero的引用才能使其正常工作

<Window ...
    xmlns:Microsoft_Windows_Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero">
<Window.Resources>
    <Geometry x:Key="DownArrowGeometry">M 0 0 L 3.5 4 L 7 0 Z</Geometry>
    <Style x:Key="ComboBoxReadonlyToggleButton" TargetType="{x:Type ToggleButton}">
        <Setter Property="OverridesDefaultStyle" Value="true"/>
        <Setter Property="IsTabStop" Value="false"/>
        <Setter Property="Focusable" Value="false"/>
        <Setter Property="ClickMode" Value="Press"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ToggleButton}">
                    <Microsoft_Windows_Themes:ButtonChrome x:Name="Chrome" BorderBrush="{TemplateBinding BorderBrush}" Background="{TemplateBinding Background}" RenderMouseOver="{TemplateBinding IsMouseOver}" RenderPressed="{TemplateBinding IsPressed}" SnapsToDevicePixels="true">
                        <Grid HorizontalAlignment="Right" Width="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}">
                            <Path x:Name="Arrow" Data="{StaticResource DownArrowGeometry}" Fill="Black" HorizontalAlignment="Center" Margin="3,1,0,0" VerticalAlignment="Center"/>
                        </Grid>
                    </Microsoft_Windows_Themes:ButtonChrome>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsChecked" Value="true">
                            <Setter Property="RenderPressed" TargetName="Chrome" Value="true"/>
                        </Trigger>
                        <Trigger Property="IsEnabled" Value="false">
                            <Setter Property="Fill" TargetName="Arrow" Value="#AFAFAF"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <ControlTemplate x:Key="comboBoxTemplate" TargetType="{x:Type ComboBox}">
        <Grid x:Name="MainGrid" SnapsToDevicePixels="true">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*"/>
                <ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
            </Grid.ColumnDefinitions>
            <Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}" Margin="1" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
                <Microsoft_Windows_Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=MainGrid}">
                    <Border x:Name="DropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1">

                        <!-- ONLY CHANGE MADE FROM ORIGINAL TEMPLATE -->
                        <Border.Background>
                            <ImageBrush ImageSource="pack://application:,,,/Images/Style/Player/Static/Red.png"/>
                        </Border.Background>
                        <!-- END OF CHANGE FROM ORIGINAL TEMPLATE -->

                        <ScrollViewer x:Name="DropDownScrollViewer">
                            <Grid RenderOptions.ClearTypeHint="Enabled">
                                <Canvas HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
                                    <Rectangle x:Name="OpaqueRect" Fill="{Binding Background, ElementName=DropDownBorder}" Height="{Binding ActualHeight, ElementName=DropDownBorder}" Width="{Binding ActualWidth, ElementName=DropDownBorder}"/>
                                </Canvas>
                                <ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                            </Grid>
                        </ScrollViewer>
                    </Border>
                </Microsoft_Windows_Themes:SystemDropShadowChrome>
            </Popup>
            <ToggleButton BorderBrush="{TemplateBinding BorderBrush}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxReadonlyToggleButton}"/>
            <ContentPresenter ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}" ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" Content="{TemplateBinding SelectionBoxItem}" ContentStringFormat="{TemplateBinding SelectionBoxItemStringFormat}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" IsHitTestVisible="false" Margin="{TemplateBinding Padding}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
        </Grid>
        <ControlTemplate.Triggers>
            <Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
                <Setter Property="Margin" TargetName="Shdw" Value="0,0,5,5"/>
                <Setter Property="Color" TargetName="Shdw" Value="#71000000"/>
            </Trigger>
            <Trigger Property="HasItems" Value="false">
                <Setter Property="Height" TargetName="DropDownBorder" Value="95"/>
            </Trigger>
            <Trigger Property="IsEnabled" Value="false">
                <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
                <Setter Property="Background" Value="#FFF4F4F4"/>
            </Trigger>
            <Trigger Property="IsGrouping" Value="true">
                <Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
            </Trigger>
            <Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
                <Setter Property="Canvas.Top" TargetName="OpaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
                <Setter Property="Canvas.Left" TargetName="OpaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
            </Trigger>
        </ControlTemplate.Triggers>
    </ControlTemplate>
</Window.Resources>

<ComboBox Template="{StaticResource comboBoxTemplate}" .../>

WPF - Comboboxitems - 一般背景图像

2 个答案: