Question

我正在尝试更改ComboBox的边框 - 这看似简单的任务，但是没有任何事情发生。

修改

这是我的代码：

以下内容出现在事件中：

cmb.BorderThickness = new Thickness(3);
cmb.BorderBrush = Brushes.Green;

这是XAML：

    <UserControl x:Class="QueryBuilder.FilterWindow"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" MaxHeight="200" Background="White" PreviewMouseLeftButtonDown="UserControl_PreviewMouseLeftButtonDown">
    <UserControl.Resources>
        <Style TargetType="TextBox">
            <Setter Property="VerticalAlignment" Value="Center"/>
            <Setter Property="BorderBrush" Value="Silver"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="SnapsToDevicePixels" Value="True"/>
            <Setter Property="OverridesDefaultStyle" Value="True"/>
            <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
            <Setter Property="AllowDrop" Value="true"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type TextBoxBase}">
                        <Border Name="Border" Padding="1" Background="#FFFFFF" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" >
                            <ScrollViewer Margin="0" x:Name="PART_ContentHost"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsEnabled" Value="False">
                                <Setter TargetName="Border" Property="Background" Value="#EEEEEE"/>
                                <Setter TargetName="Border" Property="BorderBrush" Value="#EEEEEE"/>
                                <Setter Property="Foreground" Value="#888888"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
        <Style TargetType="TreeViewItem">
            <Setter Property="Template" Value="{StaticResource TreeViewWithLines}"/>
            <Setter Property="Padding" Value="0,5,0,5"/>
            <Setter Property="IsExpanded" Value="true"/>
        </Style>
    </UserControl.Resources>
    <ScrollViewer ScrollViewer.HorizontalScrollBarVisibility="Auto" ScrollViewer.VerticalScrollBarVisibility="Auto">
        <TreeView Name="tvFilters" Margin="0,10,0,10" Background="White" BorderBrush="White"/>
    </ScrollViewer>
</UserControl>

我正在使用ComboBox的默认controltemplate，所以我不知道为什么它不起作用。有什么想法吗？

Answer 1

当我想修改样式时我会做什么，我使用WPF Inspector（你可以在那里找到它：http://wpfinspector.codeplex.com/）

然后附加到您的ComboBox，您可以访问所有属性和样式...您可以实时修改它们并查看结果，它很快......

也许你的边框是空的？或厚度为0？

Answer 2

您应该定义新的ControlTemplate，here您拥有所有代码。

如果您想要更改ComboBox的边框，则应复制并粘贴msdn的代码，并仅更改以下样式：

<Style x:Key="{x:Type ComboBox}" TargetType="ComboBox">
    <Setter Property="SnapsToDevicePixels" Value="true"/>
    <Setter Property="OverridesDefaultStyle" Value="true"/>
    <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
    <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
    <Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
    <Setter Property="MinWidth" Value="120"/>
    <Setter Property="MinHeight" Value="20"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ComboBox">
                <Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}">
                    <Grid>
                        <ToggleButton 
                        Name="ToggleButton" 
                        Template="{StaticResource ComboBoxToggleButton}" 
                        Grid.Column="2" 
                        Focusable="false"
                        IsChecked="{Binding Path=IsDropDownOpen,Mode=TwoWay,RelativeSource={RelativeSource TemplatedParent}}"
                        ClickMode="Press">
                        </ToggleButton>
                        <ContentPresenter
                        Name="ContentSite"
                        IsHitTestVisible="False" 
                        Content="{TemplateBinding SelectionBoxItem}"
                        ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
                        ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
                        Margin="3,3,23,3"
                        VerticalAlignment="Center"
                        HorizontalAlignment="Left" />
                        <TextBox x:Name="PART_EditableTextBox"
                             Style="{x:Null}" 
                             Template="{StaticResource ComboBoxTextBox}" 
                             HorizontalAlignment="Left" 
                             VerticalAlignment="Center" 
                             Margin="3,3,23,3"
                             Focusable="True" 
                             Background="Transparent"
                             Visibility="Hidden"
                             IsReadOnly="{TemplateBinding IsReadOnly}"/>
                        <Popup 
                        Name="Popup"
                        Placement="Bottom"
                        IsOpen="{TemplateBinding IsDropDownOpen}"
                        AllowsTransparency="True" 
                        Focusable="False"
                        PopupAnimation="Slide">
                            <Grid 
                            Name="DropDown"
                            SnapsToDevicePixels="True"                
                            MinWidth="{TemplateBinding ActualWidth}"
                            MaxHeight="{TemplateBinding MaxDropDownHeight}">
                                <Border 
                                x:Name="DropDownBorder"
                                Background="{StaticResource WindowBackgroundBrush}"
                                BorderThickness="1"
                                BorderBrush="{StaticResource SolidBorderBrush}"/>
                                <ScrollViewer Margin="4,6,4,6" SnapsToDevicePixels="True">
                                    <StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" />
                                </ScrollViewer>
                            </Grid>
                        </Popup>
                    </Grid>
                </Border>
                <ControlTemplate.Triggers>
                    <Trigger Property="HasItems" Value="false">
                        <Setter TargetName="DropDownBorder" Property="MinHeight" Value="95"/>
                    </Trigger>
                    <Trigger Property="IsEnabled" Value="false">
                        <Setter Property="Foreground" Value="{StaticResource DisabledForegroundBrush}"/>
                    </Trigger>
                    <Trigger Property="IsGrouping" Value="true">
                        <Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
                    </Trigger>
                    <Trigger SourceName="Popup" Property="Popup.AllowsTransparency" Value="true">
                        <Setter TargetName="DropDownBorder" Property="CornerRadius" Value="4"/>
                        <Setter TargetName="DropDownBorder" Property="Margin" Value="0,2,0,0"/>
                    </Trigger>
                    <Trigger Property="IsEditable"
                             Value="true">
                        <Setter Property="IsTabStop" Value="false"/>
                        <Setter TargetName="PART_EditableTextBox" Property="Visibility"    Value="Visible"/>
                        <Setter TargetName="ContentSite" Property="Visibility" Value="Hidden"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <Style.Triggers>
    </Style.Triggers>
</Style>

使用示例：

XAML：

<ComboBox Height="30" Width="150" BorderBrush="Red" BorderThickness="6" />

结果：

enter image description here

XAML：

<ComboBox Height="30" Width="150" BorderBrush="Green" BorderThickness="3" />

结果：

enter image description here

无法更改财产

2 个答案: