DragMove() 会使有cornerRadius 的Border 失去鼠标悬停触发状态？

Question

我创建了一个带圆角的无边框窗口，并为其添加了拖动事件和触发器。这是简单的代码：

<Window x:Class="DebugTest.MainWindow"
        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:DebugTest"
        mc:Ignorable="d" Height="200" Width="200"
        AllowsTransparency="True" WindowStyle="None" Background="Transparent">
    <Border x:Name="MainBorder" CornerRadius="15" Background="White" BorderBrush="Black" BorderThickness="1">
        <Grid>
            <Grid.Style>
                <Style TargetType="Grid">
                    <Setter Property="Visibility" Value="Hidden" />
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding ElementName=MainBorder,Path=IsMouseOver}" Value="True">
                            <Setter Property="Visibility" Value="Visible"/>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </Grid.Style>
            <Button Content="x" HorizontalAlignment="Right" VerticalAlignment="Top" 
                    Margin="5" Height="20" Width="20" Click="Button_Click"/>
        </Grid>
    </Border>
</Window>

        public MainWindow()
        {
            InitializeComponent();
        }
        protected override void OnMouseLeftButtonDown(MouseButtonEventArgs e)
        {
            base.OnMouseLeftButtonDown(e);
            this.DragMove();
        }
        private void Button_Click(object sender, RoutedEventArgs e)
        {
            this.Close();
        }

但是当我运行exe文件时，点击窗口内的空白区域，按钮会出现很明显的闪烁情况。

奇怪的是，在 Visual Studio 中调试而不是双击文件时几乎不会出现这种情况，而 CornerRadius="0" 时也不会出现这种情况。

看起来它在点击时失去了鼠标悬停触发器，但我想不出任何好的方法来避免出现闪烁，并满足对圆角、的需求可拖动，并带有触发器。

Answer 1

好吧，虽然我不知道为什么只有圆角会导致 DragMove() 触发 MouseLeave 事件，但我使用后台代码而不是使用 xaml 触发器来绕过它。

    <Border x:Name="MainBorder" CornerRadius="15" Background="White" 
            BorderBrush="Black" BorderThickness="1"
            MouseEnter="MainBorder_MouseEnter" MouseLeave="MainBorder_MouseLeave">
        <Grid Visibility="Hidden" x:Name="TriggerBorder">
            <Button Content="x" HorizontalAlignment="Right" VerticalAlignment="Top" 
                    Margin="5" Height="20" Width="20" Click="Button_Click"/>
        </Grid>
    </Border>

        bool dragMoving = false;
        public MainWindow()
        {
            InitializeComponent();
        }        
        private void Button_Click(object sender, RoutedEventArgs e)
        {
            this.Close();
        }       
        protected override void OnMouseLeftButtonDown(MouseButtonEventArgs e)
        {
            base.OnMouseLeftButtonDown(e);
            dragMoving = true;
            this.DragMove();
            dragMoving = false;
        }
        private void MainBorder_MouseEnter(object sender, MouseEventArgs e)
        {
            TriggerBorder.Visibility = Visibility.Visible;
        }

        private void MainBorder_MouseLeave(object sender, MouseEventArgs e)
        {
            if (dragMoving) return;
            TriggerBorder.Visibility = Visibility.Hidden;
        }

似乎工作正常。