Question

这让我疯了。我似乎无法在我的ComboBox中获取数据模板来拉伸下拉的宽度。是什么给了什么？

<Grid x:Name="LayoutRoot" Background="White">
    <Grid.RowDefinitions>
        <RowDefinition Height="30" />
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>
    <ComboBox x:Name="SearchesComboBox" HorizontalContentAlignment="Stretch" Width="150">
        <ComboBox.ItemContainerStyle>
            <Style TargetType="ComboBoxItem">
                <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
            </Style>
        </ComboBox.ItemContainerStyle>
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <Border BorderBrush="Black" BorderThickness="1">
                    <TextBlock Text="{Binding}" Margin="2" />
                </Border>
            </DataTemplate>
        </ComboBox.ItemTemplate>
        <sys:String>Two</sys:String>
        <sys:String>Four</sys:String>
        <sys:String>Six</sys:String>
    </ComboBox>
</Grid>

Answer 1

<ComboBox.ItemContainerStyle>
    <Style TargetType="ComboBoxItem">
        <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
    </Style>
</ComboBox.ItemContainerStyle>

Answer 2

我刚刚在WPF中确认了以下工作，将HorizontalContentAlignment移动到ComboBox：

<ComboBox x:Name="SearchesComboBox" HorizontalContentAlignment="Stretch" Width="150">
  <ComboBox.ItemTemplate>
    <DataTemplate>
      <Border BorderBrush="Black" BorderThickness="1">
        <TextBlock Text="{Binding}" Margin="2" />
      </Border>
    </DataTemplate>
  </ComboBox.ItemTemplate>
  <sys:String>Two</sys:String>
  <sys:String>Four</sys:String>
  <sys:String>Six</sys:String>
</ComboBox>

如果这也解决了Silverlight中的问题，请告诉我。我看到的问题是下拉列表中的项目大小正确，而下拉列表中显示的内容没有拉伸。

Answer 3

好的，经过大约一天的摆弄，我有一个解决方案。我恨它，但它的工作原理。基本上，我反映了Silverlight的System.Windows.dll，并且我删除了ListBoxItem的默认模板（ComboBoxItem使用它）。

事实证明，在该模板中，有一个ContentPresenter，其HorizontalAlignment硬编码为Left。因此，我扯掉了模板，并为HorizontalAlignment添加了TemplateBinding，因此它可以使用ComboBoxItem的HorizontalAlignment。

话虽如此，接下来是工作代码。如果任何人有更好的方法来做到这一点，请告诉我。我还没有检查是否在3.0中修复了这个问题。我希望是的。它应该从ComboBox.HorizontalContentAlignment完全绑定。

<UserControl.Resources>
    <Style x:Key="FixedComboBoxItem" TargetType="ComboBoxItem">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="ComboBoxItem">
                    <Grid Background="{TemplateBinding Background}">
                        <vsm:VisualStateManager.VisualStateGroups>
                            <vsm:VisualStateGroup x:Name="CommonStates">
                                <vsm:VisualState x:Name="Normal" />
                                <vsm:VisualState x:Name="MouseOver">
                                    <Storyboard>
                                        <DoubleAnimation Storyboard.TargetName="fillColor" Storyboard.TargetProperty="Opacity" Duration="0" To=".35"/>
                                    </Storyboard>
                                </vsm:VisualState>
                                <vsm:VisualState x:Name="Disabled">
                                    <Storyboard>
                                        <DoubleAnimation Storyboard.TargetName="contentPresenter" Storyboard.TargetProperty="Opacity" Duration="0" To=".55" />
                                    </Storyboard>
                                </vsm:VisualState>
                            </vsm:VisualStateGroup>
                            <vsm:VisualStateGroup x:Name="SelectionStates">
                                <vsm:VisualState x:Name="Unselected" />
                                <vsm:VisualState x:Name="Selected">
                                    <Storyboard>
                                        <DoubleAnimation Storyboard.TargetName="fillColor2" Storyboard.TargetProperty="Opacity" Duration="0" To=".75"/>
                                    </Storyboard>
                                </vsm:VisualState>
                            </vsm:VisualStateGroup>
                            <vsm:VisualStateGroup x:Name="FocusStates">
                                <vsm:VisualState x:Name="Focused">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="FocusVisualElement" Storyboard.TargetProperty="Visibility" Duration="0">
                                            <DiscreteObjectKeyFrame KeyTime="0">
                                                <DiscreteObjectKeyFrame.Value>
                                                    <Visibility>Visible</Visibility>
                                                </DiscreteObjectKeyFrame.Value>
                                            </DiscreteObjectKeyFrame>
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </vsm:VisualState>
                                <vsm:VisualState x:Name="Unfocused"/>
                            </vsm:VisualStateGroup>
                        </vsm:VisualStateManager.VisualStateGroups>
                        <Rectangle x:Name="fillColor" Opacity="0" Fill="#FFBADDE9" IsHitTestVisible="False" RadiusX="1" RadiusY="1"/>
                        <Rectangle x:Name="fillColor2" Opacity="0" Fill="#FFBADDE9" IsHitTestVisible="False" RadiusX="1" RadiusY="1"/>
                        <ContentPresenter
                            x:Name="contentPresenter"
                            Content="{TemplateBinding Content}"
                            ContentTemplate="{TemplateBinding ContentTemplate}"
                            HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
                            Margin="{TemplateBinding Padding}"/>
                        <Rectangle x:Name="FocusVisualElement" Stroke="#FF6DBDD1" StrokeThickness="1" Visibility="Collapsed" RadiusX="1" RadiusY="1" />
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</UserControl.Resources>

<Grid x:Name="LayoutRoot" Background="White">
    <Grid.RowDefinitions>
        <RowDefinition Height="30" />
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>
    <ComboBox x:Name="SearchesComboBox" Width="150" ItemContainerStyle="{StaticResource FixedComboBoxItem}"  HorizontalContentAlignment="Stretch">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <Border BorderBrush="Black" BorderThickness="1" >
                    <TextBlock Text="{Binding}" Margin="2" />
                </Border>
            </DataTemplate>
        </ComboBox.ItemTemplate>
        <sys:String>Two</sys:String>
        <sys:String>Four</sys:String>
        <sys:String>Six</sys:String>
    </ComboBox>
</Grid>

在Silverlight中拉伸ComboBox内容

3 个答案: