如何在非模态对话框的顶部正确实现模态对话框？

Question

在WPF应用程序中,我想实现以下似乎不能直接起作用的行为:

在主窗口(Window1)中,用户打开非模态窗口(Window2),非模态窗口可以显示模态对话框(Window3).

问题是,只要显示模态对话框,当用户关闭对话框时,主窗口就会在后台消失(假设有其他应用程序的窗口打开).

我使用的方式有什么问题Window.Owner和Window.Show()/ Window.ShowDialog(),它是一个错误还是根本不支持的东西？

以下简单的WPF应用程序演示了此行为:

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        Window2 win = new Window2();
        win.Owner = this;
        win.Show();
    }
}

public partial class Window2 : Window
{
    public Window2()
    {
        InitializeComponent();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        Window3 win = new Window3();
        win.Owner = this;
        win.ShowDialog();
    }

    private void btnClose_Click(object sender, RoutedEventArgs e)
    {
        this.Close();
    }
}

public partial class Window3 : Window
{
    public Window3()
    {
        InitializeComponent();
    }

    private void btnClose_Click(object sender, RoutedEventArgs e)
    {
        this.Close();
    }
}

XAML Window1:

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1">

    <Button Click="Button_Click">Show non-modal window</Button>
</Window>

XAML Window2:

<Window x:Class="WpfApplication1.Window2"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window2">
    <StackPanel>
        <Button Click="Button_Click">Show modal dialog</Button>
        <Button Name="btnClose" Click="btnClose_Click">Close</Button>
    </StackPanel>
</Window>

XAML Window3:

<Window x:Class="WpfApplication1.Window3"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window3">

    <Button Name="btnClose" Click="btnClose_Click">Close</Button>
</Window>

更新:修复了代码中的复制和粘贴错误.这是.NET 3.5 SP1,如果它很重要.

Answer 1

Microsoft 将此确认为 WPF中的错误:

这不是以前版本的回归,因此它不会为此版本的产品修复该栏.我们将在未来的版本中研究这个问题.

与此同时,这可以通过在子窗口关闭时激活所有者窗口来解决.

示例代码:

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
    }

    private void NonModalButtonClick(object sender, RoutedEventArgs e)
    {
        new Window1 { Owner = this }.Show();
    }

    private void ModalButtonClick(object sender, RoutedEventArgs e)
    {
        new Window1 { Owner = this }.ShowDialog();
    }

    protected override void OnClosing(System.ComponentModel.CancelEventArgs e)
    {
        if (this.Owner != null)
        {
            this.Owner.Activate();
        }
    }
}

(请注意,解决方法将始终将主窗口置于前景中,这可能与预期的行为不同)