如何在单击另一个控件时打开WPF弹出窗口,仅使用XAML标记？

在WPF中，要使用XAML标记在单击另一个控件时打开弹出窗口，可以使用Interaction.Triggers和EventTrigger来实现。以下是一个简单的示例，展示了如何在单击按钮时打开一个弹出窗口：

首先，在XAML文件中创建一个Window，并添加一个按钮和一个弹出窗口：

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.ColumnDefinitions>
           <ColumnDefinition/>
           <ColumnDefinition/>
        </Grid.ColumnDefinitions>
       <Button x:Name="OpenPopupButton" Content="Open Popup" Margin="10"/>
        <Popup x:Name="PopupWindow" Grid.Column="1" Placement="Right" Margin="10">
           <Border Background="White" BorderBrush="Black" BorderThickness="1">
               <StackPanel>
                    <TextBlock FontWeight="Bold" Margin="10">Popup Window</TextBlock>
                    <TextBlock Margin="10">This is a popup window.</TextBlock>
                </StackPanel>
            </Border>
        </Popup>
    </Grid>
</Window>

然后，在OpenPopupButton的Interaction.Triggers中添加一个EventTrigger，并设置RoutedEvent为Button.ClickEvent。在EventTrigger中添加一个BeginStoryboard，并定义一个Storyboard，将Popup的IsOpen属性设置为True：

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.ColumnDefinitions>
           <ColumnDefinition/>
           <ColumnDefinition/>
        </Grid.ColumnDefinitions>
       <Button x:Name="OpenPopupButton" Content="Open Popup" Margin="10">
           <Interaction.Triggers>
               <EventTrigger RoutedEvent="Button.Click">
                   <BeginStoryboard>
                       <Storyboard>
                           <BooleanAnimationUsingKeyFrames Storyboard.TargetName="PopupWindow" Storyboard.TargetProperty="IsOpen">
                                <DiscreteBooleanKeyFrame KeyTime="0:0:0" Value="True"/>
                            </BooleanAnimationUsingKeyFrames>
                        </Storyboard>
                    </BeginStoryboard>
                </EventTrigger>
            </Interaction.Triggers>
        </Button>
        <Popup x:Name="PopupWindow" Grid.Column="1" Placement="Right" Margin="10">
           <Border Background="White" BorderBrush="Black" BorderThickness="1">
               <StackPanel>
                    <TextBlock FontWeight="Bold" Margin="10">Popup Window</TextBlock>
                    <TextBlock Margin="10">This is a popup window.</TextBlock>
                </StackPanel>
            </Border>
        </Popup>
    </Grid>
</Window>

现在，当您单击“Open Popup”按钮时，将打开一个弹出窗口。这个示例仅使用了XAML标记来实现功能，没有使用任何代码。