Try implementing HotkeyControl, but with a modal window

Flow.Launcher/HotkeyControl2.xaml

@@ -0,0 +1,77 @@
+<UserControl
+    x:Class="Flow.Launcher.HotkeyControl2"
+    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"
+    mc:Ignorable="d">
+    <Button
+        Width="Auto"
+        FontSize="13"
+        FontWeight="Bold"
+        Foreground="{DynamicResource Color01B}"
+        Click="GetNewHotkey">
+        <Button.Template>
+            <ControlTemplate TargetType="Button">
+                <Border
+                    x:Name="ButtonBorder"
+                    Padding="5,0,5,0"
+                    Background="{DynamicResource ButtonBackgroundColor}"
+                    BorderBrush="{DynamicResource ButtonInsideBorder}"
+                    BorderThickness="1"
+                    CornerRadius="5">
+                    <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" />
+                </Border>
+                <ControlTemplate.Triggers>
+                    <MultiTrigger>
+                        <MultiTrigger.Conditions>
+                            <Condition Property="IsMouseOver" Value="True" />
+                            <Condition Property="IsPressed" Value="True" />
+                        </MultiTrigger.Conditions>
+                        <Setter TargetName="ButtonBorder" Property="Background"
+                                Value="{DynamicResource ButtonMousePressed}" />
+                        <Setter TargetName="ButtonBorder" Property="BorderBrush"
+                                Value="{DynamicResource ButtonMousePressedInsideBorder}" />
+                    </MultiTrigger>
+                    <MultiTrigger>
+                        <MultiTrigger.Conditions>
+                            <Condition Property="IsMouseOver" Value="True" />
+                        </MultiTrigger.Conditions>
+                        <Setter TargetName="ButtonBorder" Property="Background"
+                                Value="{DynamicResource ButtonMouseOver}" />
+                    </MultiTrigger>
+                    <MultiTrigger>
+                        <MultiTrigger.Conditions>
+                            <Condition Property="IsPressed" Value="True" />
+                        </MultiTrigger.Conditions>
+                        <Setter TargetName="ButtonBorder" Property="Background"
+                                Value="{DynamicResource ButtonMousePressed}" />
+                        <Setter TargetName="ButtonBorder" Property="BorderBrush"
+                                Value="{DynamicResource CustomContextHover}" />
+                    </MultiTrigger>
+                </ControlTemplate.Triggers>
+            </ControlTemplate>
+        </Button.Template>
+        <Button.Content>
+            <ItemsControl x:Name="HotkeyList">
+                <ItemsControl.ItemsPanel>
+                    <ItemsPanelTemplate>
+                        <StackPanel Orientation="Horizontal" />
+                    </ItemsPanelTemplate>
+                </ItemsControl.ItemsPanel>
+                <ItemsControl.ItemTemplate>
+                    <DataTemplate>
+                        <Border
+                            Margin="2,5,2,5"
+                            Padding="10,5,10,5"
+                            Background="{DynamicResource AccentButtonBackground}"
+                            BorderThickness="1"
+                            CornerRadius="5">
+                            <TextBlock Text="{Binding}" />
+                        </Border>
+                    </DataTemplate>
+                </ItemsControl.ItemTemplate>
+            </ItemsControl>
+        </Button.Content>
+    </Button>
+</UserControl>

Flow.Launcher/HotkeyControl2.xaml.cs

@@ -0,0 +1,207 @@
+#nullable enable
+
+using System.Collections.ObjectModel;
+using System.Windows;
+using System.Windows.Input;
+using Flow.Launcher.Core.Resource;
+using Flow.Launcher.Helper;
+using Flow.Launcher.Infrastructure.Hotkey;
+
+namespace Flow.Launcher
+{
+    public partial class HotkeyControl2
+    {
+        public string WindowTitle { get; set; } = string.Empty;
+
+        public static readonly DependencyProperty WindowTitleProperty = DependencyProperty.Register(
+            nameof(WindowTitle),
+            typeof(string),
+            typeof(HotkeyControl2),
+            new PropertyMetadata(default(string))
+        );
+
+        /// <summary>
+        /// Designed for Preview Hotkey and KeyGesture.
+        /// </summary>
+        public static readonly DependencyProperty ValidateKeyGestureProperty = DependencyProperty.Register(
+            nameof(ValidateKeyGesture),
+            typeof(bool),
+            typeof(HotkeyControl2),
+            new PropertyMetadata(default(bool))
+        );
+
+        public bool ValidateKeyGesture
+        {
+            get { return (bool)GetValue(ValidateKeyGestureProperty); }
+            set { SetValue(ValidateKeyGestureProperty, value); }
+        }
+
+        public static readonly DependencyProperty DefaultHotkeyProperty = DependencyProperty.Register(
+            nameof(DefaultHotkey),
+            typeof(string),
+            typeof(HotkeyControl2),
+            new PropertyMetadata(default(string))
+        );
+
+        public string DefaultHotkey
+        {
+            get { return (string)GetValue(DefaultHotkeyProperty); }
+            set { SetValue(DefaultHotkeyProperty, value); }
+        }
+
+        private static void OnHotkeyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            if (d is not HotkeyControl2 hotkeyControl)
+            {
+                return;
+            }
+
+            hotkeyControl.SetKeysToDisplay(new HotkeyModel(hotkeyControl.Hotkey));
+            hotkeyControl.CurrentHotkey = new HotkeyModel(hotkeyControl.Hotkey);
+        }
+
+
+        public static readonly DependencyProperty ChangeHotkeyProperty = DependencyProperty.Register(
+            nameof(ChangeHotkey),
+            typeof(ICommand),
+            typeof(HotkeyControl2),
+            new PropertyMetadata(default(ICommand))
+        );
+
+        public ICommand? ChangeHotkey
+        {
+            get { return (ICommand)GetValue(ChangeHotkeyProperty); }
+            set { SetValue(ChangeHotkeyProperty, value); }
+        }
+
+
+        public static readonly DependencyProperty HotkeyProperty = DependencyProperty.Register(
+            nameof(Hotkey),
+            typeof(string),
+            typeof(HotkeyControl2),
+            new FrameworkPropertyMetadata("", FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnHotkeyChanged)
+        );
+
+        public string Hotkey
+        {
+            get { return (string)GetValue(HotkeyProperty); }
+            set { SetValue(HotkeyProperty, value); }
+        }
+
+        public HotkeyControl2()
+        {
+            InitializeComponent();
+
+            HotkeyList.ItemsSource = KeysToDisplay;
+            SetKeysToDisplay(CurrentHotkey);
+        }
+
+        private static bool CheckHotkeyAvailability(HotkeyModel hotkey, bool validateKeyGesture) =>
+            hotkey.Validate(validateKeyGesture) && HotKeyMapper.CheckAvailability(hotkey);
+
+        public string EmptyHotkey => InternationalizationManager.Instance.GetTranslation("none");
+
+        public ObservableCollection<string> KeysToDisplay { get; set; } = new();
+
+        public HotkeyModel CurrentHotkey { get; private set; } = new(false, false, false, false, Key.None);
+
+
+        public void GetNewHotkey(object sender, RoutedEventArgs e)
+        {
+            if (!string.IsNullOrEmpty(Hotkey))
+            {
+                HotKeyMapper.RemoveHotkey(Hotkey);
+            }
+
+            var owner = Window.GetWindow(this);
+            var width = owner?.ActualWidth ?? 0;
+            var height = owner?.ActualHeight ?? 0;
+            var w = new HotkeyControl2Dialog
+            {
+                Title = WindowTitle,
+                Owner = owner,
+                Width = width,
+                Height = height
+            };
+            w.ShowDialog();
+            switch (w.ResultType)
+            {
+                case HotkeyControl2Dialog.EResultType.Cancel:
+                    return;
+                case HotkeyControl2Dialog.EResultType.Save:
+                    SetHotkey(w.ResultValue);
+                    break;
+                case HotkeyControl2Dialog.EResultType.Reset:
+                    ResetToDefault();
+                    break;
+                case HotkeyControl2Dialog.EResultType.Delete:
+                    Delete();
+                    break;
+            }
+        }
+
+        private void ResetToDefault()
+        {
+            if (!string.IsNullOrEmpty(Hotkey))
+                HotKeyMapper.RemoveHotkey(Hotkey);
+            Hotkey = DefaultHotkey;
+            CurrentHotkey = new HotkeyModel(Hotkey);
+
+            SetKeysToDisplay(CurrentHotkey);
+
+            SetHotkey(CurrentHotkey);
+        }
+
+
+        private void SetHotkey(HotkeyModel keyModel, bool triggerValidate = true)
+        {
+            if (triggerValidate)
+            {
+                bool hotkeyAvailable = CheckHotkeyAvailability(keyModel, ValidateKeyGesture);
+
+                if (!hotkeyAvailable)
+                {
+                    return;
+                }
+
+                Hotkey = keyModel.ToString();
+                SetKeysToDisplay(CurrentHotkey);
+                ChangeHotkey?.Execute(keyModel);
+            }
+            else
+            {
+                Hotkey = keyModel.ToString();
+                ChangeHotkey?.Execute(keyModel);
+            }
+        }
+
+        public void Delete()
+        {
+            if (!string.IsNullOrEmpty(Hotkey))
+                HotKeyMapper.RemoveHotkey(Hotkey);
+            Hotkey = "";
+            SetKeysToDisplay(new HotkeyModel(false, false, false, false, Key.None));
+        }
+
+        private void SetKeysToDisplay(HotkeyModel? hotkey)
+        {
+            KeysToDisplay.Clear();
+
+            if (hotkey == null || hotkey == default(HotkeyModel))
+            {
+                KeysToDisplay.Add(EmptyHotkey);
+                return;
+            }
+
+            foreach (var key in hotkey.Value.EnumerateDisplayKeys()!)
+            {
+                KeysToDisplay.Add(key);
+            }
+        }
+
+        public void SetHotkey(string? keyStr, bool triggerValidate = true)
+        {
+            SetHotkey(new HotkeyModel(keyStr), triggerValidate);
+        }
+    }
+}

Flow.Launcher/HotkeyControl2Dialog.xaml

@@ -0,0 +1,76 @@
+<Window x:Class="Flow.Launcher.HotkeyControl2Dialog"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        WindowStartupLocation="CenterOwner"
+        Width="400"
+        Height="300"
+        MinWidth="400"
+        MinHeight="300"
+        DataContext="{Binding RelativeSource={RelativeSource Self}}"
+        Icon="Images\app.ico"
+        ResizeMode="NoResize"
+        ShowInTaskbar="False"
+        Background="Transparent"
+        AllowsTransparency="True"
+        WindowStyle="None"
+        PreviewKeyDown="OnPreviewKeyDown">
+    <WindowChrome.WindowChrome>
+        <WindowChrome
+            CaptionHeight="0"
+            GlassFrameThickness="0" />
+    </WindowChrome.WindowChrome>
+    <Border Background="#AA000000" CornerRadius="8">
+        <Border Background="DarkGray" Width="400" Height="300" HorizontalAlignment="Center" VerticalAlignment="Center"
+                CornerRadius="8">
+            <Grid>
+                <Grid.ColumnDefinitions>
+                    <ColumnDefinition Width="*" />
+                    <ColumnDefinition Width="Auto" />
+                </Grid.ColumnDefinitions>
+                <Grid.RowDefinitions>
+                    <RowDefinition Height="*" />
+                    <RowDefinition Height="Auto" />
+                </Grid.RowDefinitions>
+
+                <Grid Grid.Row="0" Grid.Column="0">
+                    <Grid.RowDefinitions>
+                        <RowDefinition Height="Auto" />
+                        <RowDefinition Height="*" />
+                    </Grid.RowDefinitions>
+                    <TextBlock Grid.Row="0" Text="{Binding Title}" />
+                    <StackPanel Grid.Row="1" VerticalAlignment="Center" HorizontalAlignment="Center">
+                        <ItemsControl ItemsSource="{Binding KeysToDisplay}">
+                            <ItemsControl.ItemsPanel>
+                                <ItemsPanelTemplate>
+                                    <StackPanel Orientation="Horizontal"/>
+                                </ItemsPanelTemplate>
+                            </ItemsControl.ItemsPanel>
+                            <ItemsControl.ItemTemplate>
+                                <DataTemplate>
+                                    <Border Background="Red" CornerRadius="6" Padding="8" Margin="0 0 10 0">
+                                        <TextBlock Text="{Binding}" />
+                                    </Border>
+                                </DataTemplate>
+                            </ItemsControl.ItemTemplate>
+                        </ItemsControl>
+                    </StackPanel>
+                </Grid>
+
+                <Border Grid.Row="0" Grid.Column="1" Background="Gray" CornerRadius="0 8 0 0">
+                    <StackPanel>
+                        <Button Content="Reset" Click="Reset" />
+                        <Button Content="Delete" Click="Delete" />
+                    </StackPanel>
+                </Border>
+
+                <Border Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" Background="Black" CornerRadius="0 0 8 8">
+                    <StackPanel HorizontalAlignment="Center" Orientation="Horizontal" Margin="10">
+
+                        <Button Content="Save" Margin="0 0 10 0" Click="Save" />
+                        <Button Content="Cancel" Click="Cancel" />
+                    </StackPanel>
+                </Border>
+            </Grid>
+        </Border>
+    </Border>
+</Window>

Flow.Launcher/HotkeyControl2Dialog.xaml.cs

@@ -0,0 +1,93 @@
+using System.Collections.ObjectModel;
+using System.Windows;
+using System.Windows.Input;
+using Flow.Launcher.Core.Resource;
+using Flow.Launcher.Infrastructure.Hotkey;
+using Flow.Launcher.Plugin;
+
+namespace Flow.Launcher;
+
+public partial class HotkeyControl2Dialog : Window
+{
+    public string Hotkey { get; set; } = string.Empty;
+    public HotkeyModel CurrentHotkey { get; set; } = new(false, false, false, false, Key.None);
+    public ObservableCollection<string> KeysToDisplay { get; set; } = new();
+
+    public enum EResultType
+    {
+        Cancel,
+        Save,
+        Reset,
+        Delete
+    }
+
+    public EResultType ResultType { get; private set; } = EResultType.Cancel;
+    public string ResultValue { get; private set; } = string.Empty;
+    public string EmptyHotkey => InternationalizationManager.Instance.GetTranslation("none");
+    public HotkeyControl2Dialog()
+    {
+        InitializeComponent();
+    }
+
+    public void Reset(object sender, RoutedEventArgs routedEventArgs)
+    {
+        ResultType = EResultType.Reset;
+        Close();
+    }
+
+    public void Delete(object sender, RoutedEventArgs routedEventArgs)
+    {
+        ResultType = EResultType.Delete;
+        Close();
+    }
+
+    public void Cancel(object sender, RoutedEventArgs routedEventArgs)
+    {
+        ResultType = EResultType.Cancel;
+        Close();
+    }
+
+    public void Save(object sender, RoutedEventArgs routedEventArgs)
+    {
+        ResultType = EResultType.Save;
+        ResultValue = string.Join("+", KeysToDisplay);
+        Close();
+    }
+
+    private void OnPreviewKeyDown(object sender, KeyEventArgs e)
+    {
+        e.Handled = true;
+
+        //when alt is pressed, the real key should be e.SystemKey
+        Key key = e.Key == Key.System ? e.SystemKey : e.Key;
+
+        SpecialKeyState specialKeyState = GlobalHotkey.CheckModifiers();
+
+        var hotkeyModel = new HotkeyModel(
+            specialKeyState.AltPressed,
+            specialKeyState.ShiftPressed,
+            specialKeyState.WinPressed,
+            specialKeyState.CtrlPressed,
+            key);
+
+        CurrentHotkey = hotkeyModel;
+        SetKeysToDisplay(CurrentHotkey);
+    }
+
+    private void SetKeysToDisplay(HotkeyModel? hotkey)
+    {
+        KeysToDisplay.Clear();
+
+        if (hotkey == null || hotkey == default(HotkeyModel))
+        {
+            KeysToDisplay.Add(EmptyHotkey);
+            return;
+        }
+
+        foreach (var key in hotkey.Value.EnumerateDisplayKeys()!)
+        {
+            KeysToDisplay.Add(key);
+        }
+    }
+
+}

Flow.Launcher/SettingWindow.xaml

@@ -2641,7 +2641,7 @@
                                         Title="{DynamicResource flowlauncherHotkey}"
                                         Icon=""
                                         Sub="{DynamicResource flowlauncherHotkeyToolTip}">
-                                        <flowlauncher:HotkeyControl
+                                        <flowlauncher:HotkeyControl2
                                             ChangeHotkey="{Binding SetTogglingHotkeyCommand}"
                                             DefaultHotkey="Alt+Space"
                                             Hotkey="{Binding Settings.Hotkey}"
@@ -2654,9 +2654,10 @@
                                         Title="{DynamicResource previewHotkey}"
                                         Icon="&#xe8a1;"
                                         Sub="{DynamicResource previewHotkeyToolTip}">
-                                        <flowlauncher:HotkeyControl
+                                        <flowlauncher:HotkeyControl2
                                             DefaultHotkey="F1"
                                             Hotkey="{Binding Settings.PreviewHotkey}"
+                                            WindowTitle="Preview hotkey"
                                             ValidateKeyGesture="False" />
                                     </cc:Card>
                                 </StackPanel>