Completed instance handling for browser and taskbar button implementation.

SafeExamBrowser.Browser/BrowserApplicationController.cs

@@ -48,20 +48,36 @@ namespace SafeExamBrowser.Browser
 		public void RegisterApplicationButton(ITaskbarButton button)
 		{
 			this.button = button;
-			this.button.OnClick += ButtonClick;
+			this.button.OnClick += Button_OnClick;
 		}
 
 		public void Terminate()
 		{
 			foreach (var instance in instances)
 			{
+				instance.OnTerminated -= Instance_OnTerminated;
 				instance.Window.Close();
 			}
 
 			Cef.Shutdown();
 		}
 
-		private void ButtonClick(Guid? instanceId = null)
+		private void CreateNewInstance()
+		{
+			var control = new BrowserControl("www.duckduckgo.com");
+			var window = uiFactory.CreateBrowserWindow(control);
+			var instance = new BrowserApplicationInstance("DuckDuckGo");
+
+			instance.RegisterWindow(window);
+			instance.OnTerminated += Instance_OnTerminated;
+
+			button.RegisterInstance(instance);
+			instances.Add(instance);
+
+			window.Show();
+		}
+
+		private void Button_OnClick(Guid? instanceId = null)
 		{
 			if (instanceId.HasValue)
 			{
@@ -73,17 +89,9 @@ namespace SafeExamBrowser.Browser
 			}
 		}
 
-		private void CreateNewInstance()
+		private void Instance_OnTerminated(Guid id)
 		{
-			var control = new BrowserControl("www.duckduckgo.com");
+			instances.Remove(instances.FirstOrDefault(i => i.Id == id));
-			var window = uiFactory.CreateBrowserWindow(control);
-			var instance = new BrowserApplicationInstance("DuckDuckGo");
-
-			instances.Add(instance);
-			instance.RegisterWindow(window);
-			button.RegisterInstance(instance);
-
-			window.Show();
 		}
 	}
 }

SafeExamBrowser.Browser/BrowserApplicationInstance.cs

@@ -18,6 +18,8 @@ namespace SafeExamBrowser.Browser
 		public string Name { get; private set; }
 		public IWindow Window { get; private set; }
 
+		public event TerminationEventHandler OnTerminated;
+
 		public BrowserApplicationInstance(string name)
 		{
 			Id = Guid.NewGuid();
@@ -27,6 +29,7 @@ namespace SafeExamBrowser.Browser
 		public void RegisterWindow(IWindow window)
 		{
 			Window = window;
+			Window.OnClose += () => OnTerminated?.Invoke(Id);
 		}
 	}
 }

SafeExamBrowser.Contracts/Configuration/IApplicationInstance.cs

@@ -11,6 +11,8 @@ using SafeExamBrowser.Contracts.UserInterface;
 
 namespace SafeExamBrowser.Contracts.Configuration
 {
+	public delegate void TerminationEventHandler(Guid id);
+
 	public interface IApplicationInstance
 	{
 		/// <summary>
@@ -23,6 +25,11 @@ namespace SafeExamBrowser.Contracts.Configuration
 		/// </summary>
 		string Name { get; }
 
+		/// <summary>
+		/// Event fired when the application instance has been terminated.
+		/// </summary>
+		event TerminationEventHandler OnTerminated;
+
 		/// <summary>
 		/// The main window of the application instance.
 		/// </summary>

SafeExamBrowser.Contracts/UserInterface/ITaskbarButton.cs

@@ -22,15 +22,8 @@ namespace SafeExamBrowser.Contracts.UserInterface
 		event TaskbarButtonClickHandler OnClick;
 
 		/// <summary>
-		/// Registers a new instance of an application, to be displayed if the user clicks the taskbar button
+		/// Registers a new instance of an application, to be displayed if the user clicks the taskbar button.
-		/// when there are already one or more instances of the same application running.
 		/// </summary>
 		void RegisterInstance(IApplicationInstance instance);
-
-		/// <summary>
-		/// Unregisters an application instance, e.g. if it gets closed.
-		/// </summary>
-		/// <param name="id">The identifier for the application instance.</param>
-		void UnregisterInstance(Guid id);
 	}
 }

SafeExamBrowser.Contracts/UserInterface/IWindow.cs

@@ -8,8 +8,15 @@
 
 namespace SafeExamBrowser.Contracts.UserInterface
 {
+	public delegate void WindowCloseHandler();
+
 	public interface IWindow
 	{
+		/// <summary>
+		/// Event fired when the window is closing.
+		/// </summary>
+		event WindowCloseHandler OnClose;
+
 		/// <summary>
 		/// Brings the window to the foreground.
 		/// </summary>

SafeExamBrowser.Core/Behaviour/ShutdownController.cs

@@ -8,7 +8,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Threading;
 using SafeExamBrowser.Contracts.Behaviour;
 using SafeExamBrowser.Contracts.Configuration;
 using SafeExamBrowser.Contracts.I18n;
@@ -54,9 +53,6 @@ namespace SafeExamBrowser.Core.Behaviour
 			{
 				operation.SplashScreen = splashScreen;
 				operation.Revert();
-
-				// TODO: Remove!
-				Thread.Sleep(250);
 			}
 		}
 

SafeExamBrowser.Core/Behaviour/StartupController.cs

@@ -9,7 +9,6 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading;
 using SafeExamBrowser.Contracts.Behaviour;
 using SafeExamBrowser.Contracts.Configuration;
 using SafeExamBrowser.Contracts.I18n;
@@ -66,9 +65,6 @@ namespace SafeExamBrowser.Core.Behaviour
 				operation.Perform();
 
 				splashScreen.Progress();
-
-				// TODO: Remove!
-				Thread.Sleep(250);
 			}
 		}
 
@@ -80,9 +76,6 @@ namespace SafeExamBrowser.Core.Behaviour
 
 				operation.Revert();
 				splashScreen.Regress();
-
-				// TODO: Remove!
-				Thread.Sleep(250);
 			}
 		}
 

SafeExamBrowser.UserInterface/BrowserWindow.xaml.cs

@@ -19,6 +19,8 @@ namespace SafeExamBrowser.UserInterface
 			InitializeBrowserWindow(browserControl);
 		}
 
+		public event WindowCloseHandler OnClose;
+
 		public void BringToForeground()
 		{
 			if (WindowState == WindowState.Minimized)
@@ -35,6 +37,8 @@ namespace SafeExamBrowser.UserInterface
 			{
 				BrowserControlHost.Child = browserControl as System.Windows.Forms.Control;
 			}
+
+			Closing += (o, args) => OnClose?.Invoke();
 		}
 	}
 }

SafeExamBrowser.UserInterface/Controls/ApplicationButton.xaml.cs

@@ -36,23 +36,15 @@ namespace SafeExamBrowser.UserInterface.Controls
 		{
 			var instanceButton = new ApplicationInstanceButton(instance, info);
 
-			instances.Add(instance);
 			instanceButton.Click += (id) => OnClick?.Invoke(id);
+			instance.OnTerminated += (id) => Instance_OnTerminated(id, instanceButton);
+
+			instances.Add(instance);
 			InstanceStackPanel.Children.Add(instanceButton);
 
 			ActiveBar.Visibility = Visibility.Visible;
 		}
 
-		public void UnregisterInstance(Guid id)
-		{
-			instances.Remove(instances.FirstOrDefault(i => i.Id == id));
-
-			if (!instances.Any())
-			{
-				ActiveBar.Visibility = Visibility.Collapsed;
-			}
-		}
-
 		private void InitializeApplicationButton()
 		{
 			Button.ToolTip = info.Tooltip;
@@ -84,5 +76,16 @@ namespace SafeExamBrowser.UserInterface.Controls
 				InstancePopup.IsOpen = true;
 			}
 		}
+
+		private void Instance_OnTerminated(Guid id, ApplicationInstanceButton instanceButton)
+		{
+			instances.Remove(instances.FirstOrDefault(i => i.Id == id));
+			InstanceStackPanel.Children.Remove(instanceButton);
+
+			if (!instances.Any())
+			{
+				ActiveBar.Visibility = Visibility.Collapsed;
+			}
+		}
 	}
 }