[Bug]: The Close method cannot be called in code when using a modal window

[hoshiizumiya]

Describe the bug

As dev/DevWinUI/Common/Window/ModalWindow.cs.
Idk why I can't call Close() in the code if I use ModalWindow.

Steps to reproduce the bug

You can use btnCancel.Click += (s, e) => Close(); if you use Window, but can't in the ModalWindow.

Expected behavior

No response

Screenshots

No response

NuGet package version

None

IDE

Visual Studio 2026

Additional context

No response

[ghost1372]

Hi @hoshiizumiya
i dont see any issues!

<dev:ModalWindow x:Class="App10.BlankWindow1"
                 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:dev="using:DevWinUI"
                 xmlns:local="using:App10"
                 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                 Title="BlankWindow1"
                 mc:Ignorable="d">


    <StackPanel>
        <TextBlock HorizontalAlignment="Center"
                   VerticalAlignment="Center"
                   FontSize="68"
                   Text="Modal Window" />
        <Button Content="close" Click="Button_Click"/>
    </StackPanel>
</dev:ModalWindow>

public sealed partial class BlankWindow1 : ModalWindow
{
    public BlankWindow1(IntPtr parentHwnd) : base(parentHwnd)
    {
        InitializeComponent();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        Close();
    }
}

<?xml version="1.0" encoding="utf-8" ?>
<Window x:Class="App10.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:dev="using:DevWinUI"
        xmlns:local="using:App10"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        Title="App10"
        mc:Ignorable="d">

    <Window.SystemBackdrop>
        <MicaBackdrop />
    </Window.SystemBackdrop>
    <StackPanel Spacing="10">
        <Button Click="Button_Click"
                Content="Open" />

    </StackPanel>
</Window>

public sealed partial class MainWindow : Window
{
    public static MainWindow Instance { get; set; }
    public MainWindow()
    {
        InitializeComponent();
        Instance = this;
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        var window = new BlankWindow1(WindowNative.GetWindowHandle(MainWindow.Instance));
        window.Activate();
    }
}