[#43] App: Use FileSystemWatcher to renew contexts on demand

Elwig/App.xaml.cs

@@ -60,6 +60,10 @@ namespace Elwig {
         public static ClientParameters Client { get; set; }
 
         public static Dispatcher MainDispatcher { get; private set; }
+        private readonly FileSystemWatcher Watcher = new(Path.GetDirectoryName(Config.DatabaseFile) ?? "C:\\") {
+            NotifyFilter = NotifyFilters.LastWrite,
+            Filter = "*.sqlite3",
+        };
 
         public App() : base() {
             System.Text.Encoding.RegisterProvider(System.Text.CodePagesEncodingProvider.Instance);
@@ -69,6 +73,12 @@ namespace Elwig {
             Scales = [];
             CurrentApp = this;
             OverrideCulture();
+            Watcher.Changed += new FileSystemEventHandler(OnChanged);
+            Watcher.EnableRaisingEvents = true;
+        }
+
+        private void OnChanged(object source, FileSystemEventArgs e) {
+            MainDispatcher.BeginInvoke(async () => await HintContextChange());
         }
 
         private static void OverrideCulture() {