Add Theme mode API Function

Flow.Launcher.Plugin/EventHandler.cs

@@ -39,7 +39,14 @@ namespace Flow.Launcher.Plugin
     /// <param name="sender"></param>
     /// <param name="args"></param>
     public delegate void VisibilityChangedEventHandler(object sender, VisibilityChangedEventArgs args);
-
+
+    /// <summary>
+    /// A delegate for when the actual application theme is changed
+    /// </summary>
+    /// <param name="sender"></param>
+    /// <param name="args"></param>
+    public delegate void ActualApplicationThemeChangedEventHandler(object sender, ActualApplicationThemeChangedEventArgs args);
+
     /// <summary>
     /// The event args for <see cref="VisibilityChangedEventHandler"/>
     /// </summary>
@@ -77,4 +84,15 @@ public class FlowLauncherQueryEventArgs
         /// </summary>
         public Query Query { get; set; }
     }
+
+    /// <summary>
+    /// The event args for <see cref="ActualApplicationThemeChangedEventHandler"/>
+    /// </summary>
+    public class ActualApplicationThemeChangedEventArgs : EventArgs
+    {
+        /// <summary>
+        /// <see langword="true"/> if the application has changed actual theme
+        /// </summary>
+        public bool IsDark { get; init; }
+    }
 }

Flow.Launcher.Plugin/Interfaces/IPublicAPI.cs

@@ -237,7 +237,7 @@
         Task<string> HttpGetStringAsync(string url, CancellationToken token = default);
 
         /// <summary>
         /// Http download the spefic url and return as stream
         /// </summary>
         /// <param name="url">URL to call Http Get</param>
         /// <param name="token">Cancellation Token</param>
@@ -393,7 +393,7 @@
 
         /// <summary>
         /// Reloads the query.
         /// When current results are from context menu or history, it will go back to query results before requerying.
         /// </summary>
         /// <param name="reselect">Choose the first result after reload if true; keep the last selected result if false. Default is true.</param>
         public void ReQuery(bool reselect = true);
@@ -595,5 +595,16 @@
         /// </summary>
         /// <returns>The time taken to execute the method in milliseconds</returns>
         public Task<long> StopwatchLogInfoAsync(string className, string message, Func<Task> action, [CallerMemberName] string methodName = "");
+
+        /// <summary>
+        /// Representing whether the application is using a dark theme
+        /// </summary>
+        /// <returns></returns>
+        bool IsApplicationDarkTheme();
+
+        /// <summary>
+        /// Invoked when the actual theme of the application has changed. Currently, the plugin will continue to be subscribed even if it is turned off. 
+        /// </summary>
+        event ActualApplicationThemeChangedEventHandler ActualApplicationThemeChanged;
     }
 }

Flow.Launcher/MainWindow.xaml.cs

@@ -20,6 +20,7 @@
 using Flow.Launcher.Infrastructure.Hotkey;
 using Flow.Launcher.Infrastructure.Image;
 using Flow.Launcher.Infrastructure.UserSettings;
+using Flow.Launcher.Plugin;
 using Flow.Launcher.Plugin.SharedCommands;
 using Flow.Launcher.ViewModel;
 using Microsoft.Win32;
@@ -80,8 +81,8 @@
         public MainWindow()
         {
             _settings = Ioc.Default.GetRequiredService<Settings>();
             _theme = Ioc.Default.GetRequiredService<Theme>();
             _viewModel = Ioc.Default.GetRequiredService<MainViewModel>();
             DataContext = _viewModel;
 
             Topmost = _settings.ShowAtTopmost;
@@ -91,8 +92,8 @@
 
             InitSoundEffects();
             DataObject.AddPastingHandler(QueryTextBox, QueryTextBox_OnPaste);
-            ModernWpf.ThemeManager.Current.ActualApplicationThemeChanged += ThemeManager_ActualApplicationThemeChanged;
             SystemEvents.PowerModeChanged += SystemEvents_PowerModeChanged;
+            _viewModel.ActualApplicationThemeChanged += ViewModel_ActualApplicationThemeChanged;
         }
 
         #endregion
@@ -101,7 +102,7 @@
 
 #pragma warning disable VSTHRD100 // Avoid async void methods
 
-        private void ThemeManager_ActualApplicationThemeChanged(ModernWpf.ThemeManager sender, object args)
+        private void ViewModel_ActualApplicationThemeChanged(object sender, ActualApplicationThemeChangedEventArgs args)
         {
             _ = _theme.RefreshFrameAsync();
         }
@@ -110,7 +111,7 @@
         {
             var handle = Win32Helper.GetWindowHandle(this, true);
             _hwndSource = HwndSource.FromHwnd(handle);
             _hwndSource.AddHook(WndProc);
             Win32Helper.HideFromAltTab(this);
             Win32Helper.DisableControlBox(this);
         }
@@ -359,7 +360,7 @@
         {
             try
             {
                 _hwndSource.RemoveHook(WndProc);
             }
             catch (Exception)
             {
@@ -483,7 +484,7 @@
             }
         }
 
 #pragma warning restore VSTHRD100 // Avoid async void methods
 
         #endregion
 
@@ -546,7 +547,7 @@
 
         #region Window Context Menu Event
 
 #pragma warning disable VSTHRD100 // Avoid async void methods
 
         private async void OnContextMenusForSettingsClick(object sender, RoutedEventArgs e)
         {
@@ -558,11 +559,11 @@
             App.API.OpenSettingDialog();
         }
 
 #pragma warning restore VSTHRD100 // Avoid async void methods
 
         #endregion
 
         #region Window WndProc
 
         private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled) 
         {
@@ -786,7 +787,7 @@
 
         private void UpdatePosition()
         {
             // Initialize call twice to work around multi-display alignment issue- https://github.com/Flow-Launcher/Flow.Launcher/issues/2910
             InitializePosition();
             InitializePosition();
         }
@@ -802,7 +803,7 @@
 
         private void InitializePosition()
         {
             // Initialize call twice to work around multi-display alignment issue- https://github.com/Flow-Launcher/Flow.Launcher/issues/2910
             InitializePositionInner();
             InitializePositionInner();
             return;
@@ -1351,7 +1352,7 @@
                     _notifyIcon?.Dispose();
                     animationSoundWMP?.Close();
                     animationSoundWPF?.Dispose();
-                    ModernWpf.ThemeManager.Current.ActualApplicationThemeChanged -= ThemeManager_ActualApplicationThemeChanged;
+                    _viewModel.ActualApplicationThemeChanged -= ViewModel_ActualApplicationThemeChanged;
                     SystemEvents.PowerModeChanged -= SystemEvents_PowerModeChanged;
                 }
 

Flow.Launcher/PublicAPIInstance.cs

@@ -14,23 +14,24 @@
 using System.Windows.Media;
 using CommunityToolkit.Mvvm.DependencyInjection;
 using Flow.Launcher.Core;
+using Flow.Launcher.Core.ExternalPlugins;
 using Flow.Launcher.Core.Plugin;
 using Flow.Launcher.Core.Resource;
-using Flow.Launcher.Core.ExternalPlugins;
 using Flow.Launcher.Core.Storage;
 using Flow.Launcher.Helper;
 using Flow.Launcher.Infrastructure;
-using Flow.Launcher.Infrastructure.Http;
 using Flow.Launcher.Infrastructure.Hotkey;
+using Flow.Launcher.Infrastructure.Http;
 using Flow.Launcher.Infrastructure.Image;
 using Flow.Launcher.Infrastructure.Logger;
 using Flow.Launcher.Infrastructure.Storage;
 using Flow.Launcher.Infrastructure.UserSettings;
 using Flow.Launcher.Plugin;
-using Flow.Launcher.Plugin.SharedModels;
 using Flow.Launcher.Plugin.SharedCommands;
+using Flow.Launcher.Plugin.SharedModels;
 using Flow.Launcher.ViewModel;
 using JetBrains.Annotations;
+using ModernWpf;
 using Squirrel;
 using Stopwatch = Flow.Launcher.Infrastructure.Stopwatch;
 
@@ -587,6 +588,17 @@ public long StopwatchLogInfo(string className, string message, Action action, [C
         public Task<long> StopwatchLogInfoAsync(string className, string message, Func<Task> action, [CallerMemberName] string methodName = "") =>
             Stopwatch.InfoAsync(className, message, action, methodName);
 
+        public bool IsApplicationDarkTheme()
+        {
+            return ThemeManager.Current.ActualApplicationTheme == ApplicationTheme.Dark;
+        }
+
+        public event ActualApplicationThemeChangedEventHandler ActualApplicationThemeChanged
+        {
+            add => _mainVM.ActualApplicationThemeChanged += value;
+            remove => _mainVM.ActualApplicationThemeChanged -= value;
+        }
+
         #endregion
 
         #region Private Methods

Flow.Launcher/ViewModel/MainViewModel.cs

@@ -22,6 +22,7 @@
 using Flow.Launcher.Plugin.SharedCommands;
 using Flow.Launcher.Storage;
 using Microsoft.VisualStudio.Threading;
+using ModernWpf;
 
 namespace Flow.Launcher.ViewModel
 {
@@ -195,6 +196,18 @@ public MainViewModel()
 
             RegisterViewUpdate();
             _ = RegisterClockAndDateUpdateAsync();
+
+            ThemeManager.Current.ActualApplicationThemeChanged += ThemeManager_ActualApplicationThemeChanged;
+        }
+
+        private void ThemeManager_ActualApplicationThemeChanged(ThemeManager sender, object args)
+        {
+            ActualApplicationThemeChanged?.Invoke(
+                Application.Current,
+                new ActualApplicationThemeChangedEventArgs()
+                {
+                    IsDark = sender.ActualApplicationTheme == ApplicationTheme.Dark
+                });
         }
 
         private void RegisterViewUpdate()
@@ -821,6 +834,7 @@ private ResultsViewModel SelectedResults
         public bool MainWindowVisibilityStatus { get; set; } = true;
 
         public event VisibilityChangedEventHandler VisibilityChanged;
+        public event ActualApplicationThemeChangedEventHandler ActualApplicationThemeChanged;
 
         public Visibility ClockPanelVisibility { get; set; }
         public Visibility SearchIconVisibility { get; set; }
@@ -1975,6 +1989,7 @@ protected virtual void Dispose(bool disposing)
                     {
                         _resultsViewUpdateTask.Dispose();
                     }
+                    ThemeManager.Current.ActualApplicationThemeChanged -= ThemeManager_ActualApplicationThemeChanged;
                     _disposed = true;
                 }
             }