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如何使ComboBox的選定項目出現在ComboBox文本字段中並使用Border s在ComboBoxControlTemplate？用下面的代碼的項目彈出不錯，但在選擇後ComboBox文本框從未露面;但是從ComboBox模板拆下2個Border小號修復此。爲什麼？？怎麼樣？？更重要的是：我怎麼使用這個模板，Border S和有SelectedItem選擇後的ComboBox文本框正確顯示？如何顯示選定的項目並使用組合框邊框？爲什麼會發生這種行爲？
<Window.Resources>
<Style x:Key="ComboboxDropdownButton" TargetType="{x:Type ToggleButton}">
<Setter Property="MinWidth" Value="0"/>
<Setter Property="MinHeight" Value="0"/>
<Setter Property="Width" Value="NaN"/>
<Setter Property="Height" Value="NaN"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="BorderBrush" Value="Black"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<DockPanel SnapsToDevicePixels="True"
Background="{TemplateBinding Background}"
LastChildFill="False">
<Border x:Name="Border"
Width="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}"
DockPanel.Dock="Right"
Background="WhiteSmoke"
CornerRadius="0,3,3,0"
BorderThickness="{TemplateBinding BorderThickness}"
BorderBrush="{TemplateBinding BorderBrush}"
>
<Path Fill="{TemplateBinding Foreground}"
HorizontalAlignment="Center" VerticalAlignment="Center" Data="M0,0L4.5,4 9,0z"/>
</Border>
</DockPanel>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="Border" Property="Background" Value="White" />
</Trigger>
<Trigger Property="IsChecked" Value="True">
<Setter TargetName="Border" Property="Background" Value="White" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Opacity" Value="0.5"/>
</Trigger>
</Style.Triggers>
</Style>
<ControlTemplate x:Key="ComboBoxTextBox" TargetType="{x:Type TextBox}">
<Border x:Name="PART_ContentHost" Focusable="False" />
</ControlTemplate>
<Style x:Key="{x:Type ComboBox}"
TargetType="{x:Type 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="{x:Type ComboBox}">
<Border SnapsToDevicePixels="True"
x:Name="OuterBorder"
Background="Transparent"
BorderBrush="Red"
BorderThickness="1"
CornerRadius="4"
Margin="-1">
<Border x:Name="InnerBorder"
Background="WhiteSmoke"
BorderThickness="1"
CornerRadius="3"
BorderBrush="Black">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="EditStates">
<VisualState x:Name="Editable">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)"
Storyboard.TargetName="PART_EditableTextBox">
<DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)"
Storyboard.TargetName="ContentSite">
<DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Hidden}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Uneditable" />
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ToggleButton x:Name="ToggleButton"
Margin="-1"
Grid.Column="2"
Focusable="False"
ClickMode="Press"
Style="{StaticResource ComboboxDropdownButton}"
IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}">
</ToggleButton>
<ContentPresenter x:Name="ContentSite"
IsHitTestVisible="False"
Content="{TemplateBinding SelectionBoxItem}"
ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
Margin="3,3,23,3"
VerticalAlignment="Stretch"
HorizontalAlignment="Left">
</ContentPresenter>
<TextBox x:Name="PART_EditableTextBox"
Style="{x:Null}"
Template="{StaticResource ComboBoxTextBox}"
HorizontalAlignment="Left"
VerticalAlignment="Bottom"
Margin="3,3,23,3"
Focusable="True"
Background="Transparent"
Visibility="Hidden"
IsReadOnly="{TemplateBinding IsReadOnly}" />
<Popup x:Name="PART_Popup"
Placement="Bottom"
IsOpen="{TemplateBinding IsDropDownOpen}"
AllowsTransparency="True"
Focusable="False"
PopupAnimation="Slide">
<Grid x:Name="DropDown"
SnapsToDevicePixels="True"
MinWidth="{TemplateBinding ActualWidth}"
MaxHeight="{TemplateBinding MaxDropDownHeight}"
>
<Border x:Name="DropDownBorder"
MaxHeight="{TemplateBinding MaxDropDownHeight}"
MinWidth="{Binding ActualWidth, ElementName=Border}"
Background="WhiteSmoke"
BorderBrush="Black"
BorderThickness="1" CornerRadius="0,0,3,3">
</Border>
<ScrollViewer Padding="1" SnapsToDevicePixels="True">
<StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" />
</ScrollViewer>
</Grid>
</Popup>
</Grid>
</Border>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="HasItems" Value="false">
<Setter TargetName="DropDownBorder" Property="MinHeight" Value="95" />
</Trigger>
<Trigger Property="IsGrouping" Value="true">
<Setter Property="ScrollViewer.CanContentScroll" Value="false" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<ComboBox Width="120" Height="20" Name="comboBox1" SnapsToDevicePixels="True"
HorizontalAlignment="Center" VerticalAlignment="Center"
Text="ComboBox" SelectedIndex="0" IsEditable="True" IsReadOnly="True">
<ComboBoxItem>item 1</ComboBoxItem>
<ComboBoxItem>item 2</ComboBoxItem>
<ComboBoxItem>item 3</ComboBoxItem>
</ComboBox>
</Grid>
只是一個完全野生的猜測......我們曾經相同的情況下幾個月回來時，組合框彈出，並選擇不間歇地在我們與邊框定製組合框模板出現了，當我們從邊境刪除'CornerRadius'屬性它去了....： -/...我知道聽起來很愚蠢，完全荒謬，但那就是實際發生的事！它是一個謎我想不出解決，直到日期...你可以downvote我，如果這個「絕望」招行不通.... :-D –
同樣奇怪的事情發生在我身上一次。也很奇怪：在.NET 3.0中，我們對TextBlock有一個DropShadowBitmap效果。它造成內存泄漏，導致我們的應用程序增加約1 MB /分鐘。 –
是的！那個也是！我們的Splash屏幕上既有圓角，又有DropShadowBitmap，它上面的Combobox表演完全荒謬！當我們移除這兩個時，它開始工作正常！ –