c# - 在日历中更改选定的日期背景(或文本)

Question

我正在学习 WPF 和 XAML。但我是新手，有一个问题。

我的目的 - 更改日历中所选日期的文本。现在，它有蓝色背景。但我想要两个括号:(...):

我看到了这个问题的两个解决方案。

首先。更改控制模板。我找到了 full template code on MSDN site .但是代码太多了，我找不到任何方法来将背景颜色替换为括号，因为我找不到“文本”属性。如果找到它，我只需将其替换为水平 StackPanel，并在日期前后添加两个带有“(”和“)”的文本框。但我不能。如果可以的话，我真的应该复制所有这些代码吗？

其次。据我所知，日历中的所有日期都是 CalendarDayButton 类型。此类型具有“上下文”属性。也许，如果我改变它，那么文本就会改变。我不知道。但是我没有直接访问这种类型。我应该获取日历的所有子项并在其中搜索选定的日期。我认为这太复杂了。

如果你知道这个问题的更优雅的解决方案 - 我将非常感谢你。

Answer 1

是的，所以您通过第一次观察回答了您的问题。因此，如果我们查看给出的 MSDN 示例中的代码并关注您的 CalendarButton Style 模板，您可以从上到下分解它的工作方式。请参阅下面复制示例中的注释。

         <!-- **********
            Ok, so we know this is the bugger we want to deal with.
            -->
            <Style TargetType="CalendarButton"
                   x:Key="CalendarButtonStyle">
              <Setter Property="MinWidth"
                      Value="40" />
              <Setter Property="MinHeight"
                      Value="42" />
              <Setter Property="FontSize"
                      Value="10" />
              <Setter Property="HorizontalContentAlignment"
                      Value="Center" />
              <Setter Property="VerticalContentAlignment"
                      Value="Center" />
              <Setter Property="Template">
                <Setter.Value>
                  <ControlTemplate TargetType="CalendarButton">
                    <Grid>
            <!-- *************
            What we want to change is the stuff that happens
        for a State, in this case the Selected State. So we just
        go look at what exactly it is doing for that Selected State.
            -->
                      <VisualStateManager.VisualStateGroups>
                        <VisualStateGroup Name="CommonStates">
                          <VisualStateGroup.Transitions>
                            <VisualTransition GeneratedDuration="0:0:0.1" />
                          </VisualStateGroup.Transitions>
                          <VisualState Name="Normal" />
                          <VisualState Name="MouseOver">
                            <Storyboard>
                              <DoubleAnimation Storyboard.TargetName="Background"
                                               Storyboard.TargetProperty="Opacity"
                                               To=".5"
                                               Duration="0" />
                            </Storyboard>
                          </VisualState>
                          <VisualState Name="Pressed">
                            <Storyboard>
                              <DoubleAnimation Storyboard.TargetName="Background"
                                               Storyboard.TargetProperty="Opacity"
                                               To=".5"
                                               Duration="0" />
                            </Storyboard>
                          </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup Name="SelectionStates">
                          <VisualStateGroup.Transitions>
                            <VisualTransition GeneratedDuration="0" />
                          </VisualStateGroup.Transitions>
                          <VisualState Name="Unselected" />
            <!-- ************
        Hey, look at that. So this guy's telling something called "SelectedBackground" 
        with some opacity to show up and be seen. Now we know we need to go check out 
        this SelectedBackground object he's talking to.
            -->
                          <VisualState Name="Selected">
                            <Storyboard>
                              <DoubleAnimation Storyboard.TargetName="SelectedBackground"
                                               Storyboard.TargetProperty="Opacity"
                                               To=".75"
                                               Duration="0" />
                            </Storyboard>
                          </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup Name="ActiveStates">
                          <VisualStateGroup.Transitions>
                            <VisualTransition GeneratedDuration="0" />
                          </VisualStateGroup.Transitions>
                          <VisualState Name="Active" />
                          <VisualState Name="Inactive">
                            <Storyboard>
                              <ColorAnimation Duration="0"
                                              Storyboard.TargetName="NormalText"
                                              Storyboard.TargetProperty="(TextElement.Foreground).
                                  (SolidColorBrush.Color)"
                                              To="#FF777777" />
                            </Storyboard>
                          </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup Name="CalendarButtonFocusStates">
                          <VisualStateGroup.Transitions>
                            <VisualTransition GeneratedDuration="0" />
                          </VisualStateGroup.Transitions>
                          <VisualState Name="CalendarButtonFocused">
                            <Storyboard>
                              <ObjectAnimationUsingKeyFrames Duration="0"
                                                             Storyboard.TargetName="CalendarButtonFocusVisual"
                                                             Storyboard.TargetProperty="Visibility">
                                <DiscreteObjectKeyFrame KeyTime="0">
                                  <DiscreteObjectKeyFrame.Value>
                                    <Visibility>Visible</Visibility>
                                  </DiscreteObjectKeyFrame.Value>
                                </DiscreteObjectKeyFrame>
                              </ObjectAnimationUsingKeyFrames>
                            </Storyboard>
                          </VisualState>
                          <VisualState Name="CalendarButtonUnfocused" />
                        </VisualStateGroup>
                      </VisualStateManager.VisualStateGroups>
            <!-- ***************
            Sneaky bugger... looks like there is something called SelectedBackground
 (Rectangle) sitting here with a 0 opacity 
waiting to be told to show himself. 
    Imagine that.
            -->
                      <Rectangle x:Name="SelectedBackground"
                                 RadiusX="1"
                                 RadiusY="1"
                                 Opacity="0">
                        <Rectangle.Fill>
                          <SolidColorBrush Color="{DynamicResource SelectedBackgroundColor}" />
                        </Rectangle.Fill>
                      </Rectangle>
                      <Rectangle x:Name="Background"
                                 RadiusX="1"
                                 RadiusY="1"
                                 Opacity="0">
                        <Rectangle.Fill>
                          <SolidColorBrush Color="{DynamicResource SelectedBackgroundColor}" />
                        </Rectangle.Fill>
                      </Rectangle>
                      <ContentPresenter x:Name="NormalText"
                                        HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                                        VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                                        Margin="1,0,1,1">
                        <TextElement.Foreground>
                          <SolidColorBrush Color="#FF333333" />
                        </TextElement.Foreground>
                      </ContentPresenter>
                      <Rectangle x:Name="CalendarButtonFocusVisual"
                                 Visibility="Collapsed"
                                 IsHitTestVisible="false"
                                 RadiusX="1"
                                 RadiusY="1">
                        <Rectangle.Stroke>
                          <SolidColorBrush Color="{DynamicResource SelectedBackgroundColor}" />
                        </Rectangle.Stroke>
                      </Rectangle>
                    </Grid>
                  </ControlTemplate>
                </Setter.Value>
              </Setter>
              <Setter Property="Background">
                <Setter.Value>
                  <SolidColorBrush Color="{DynamicResource ControlMediumColor}" />
                </Setter.Value>
              </Setter>
            </Style>

所以您找到了最初的罪魁祸首。您可以删除 Rectangle 或将其设为 Transparent 或其他。然后返回您在被指出的 VisualStateManager 中的 SelectedState 声明。编辑:我们将采用不同的方法并显示另一个元素。;

<VisualState Name="Selected">
   <Storyboard>
      <ObjectAnimationUsingKeyFrames Storyboard.TargetName="SelectedText"
                                     Storyboard.TargetProperty="Visibility">
             <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{x:Static Visibility.Visible}"/>
      </ObjectAnimationUsingKeyFrames>
      <ObjectAnimationUsingKeyFrames Storyboard.TargetName="NormalText"
                                     Storyboard.TargetProperty="Visibility">
             <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{x:Static Visibility.Collapsed}"/>
      </ObjectAnimationUsingKeyFrames>
   </Storyboard>
</VisualState>

编辑:

<!--
<ContentPresenter x:Name="NormalText"
                  HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                  VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                  Margin="1,0,1,1">
                    <TextElement.Foreground>
                      <SolidColorBrush Color="#FF333333" />
                    </TextElement.Foreground>
                  </ContentPresenter>
-->
<TextBlock x:Name="NormalText"
           Text="{TemplateBinding Content}"
           HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
           VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
           Margin="1,0,1,1"/>
<TextBlock x:Name="SelectedText" Visibility="Collapsed"
           Text="{TemplateBinding Content, StringFormat='(\{\0})'}"
           HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
           VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
           Margin="1,0,1,1"/>

现在，当按钮处于 SelectedState 时，它应该显示带有 '( )` 的 TextBlock 并隐藏没有它的那个。

无论如何，这应该会给你一个相当不错的方向，希望对你有所帮助。