SEBWIN-312: Started implementing task view.

SafeExamBrowser.Applications.Contracts/ApplicationInfo.cs

@@ -28,6 +28,6 @@ namespace SafeExamBrowser.Applications.Contracts
 		/// <summary>
 		/// The resource providing the application icon.
 		/// </summary>
-		public IconResource IconResource { get; set; }
+		public IconResource Icon { get; set; }
 	}
 }

SafeExamBrowser.Applications.Contracts/IApplicationInstance.cs

@@ -7,6 +7,7 @@
  */
 
 using SafeExamBrowser.Applications.Contracts.Events;
+using SafeExamBrowser.Core.Contracts;
 
 namespace SafeExamBrowser.Applications.Contracts
 {
@@ -15,6 +16,11 @@ namespace SafeExamBrowser.Applications.Contracts
 	/// </summary>
 	public interface IApplicationInstance
 	{
+		/// <summary>
+		/// The icon resource for this instance.
+		/// </summary>
+		IconResource Icon { get; }
+
 		/// <summary>
 		/// The unique identifier for the application instance.
 		/// </summary>

SafeExamBrowser.Applications/ApplicationFactory.cs

@@ -64,7 +64,7 @@ namespace SafeExamBrowser.Applications
 		private IApplication BuildApplication(string executablePath, WhitelistApplication settings)
 		{
 			var icon = new IconResource { Type = IconResourceType.Embedded, Uri = new Uri(executablePath) };
-			var info = new ApplicationInfo { IconResource = icon, Name = settings.DisplayName, Tooltip = settings.Description ?? settings.DisplayName };
+			var info = new ApplicationInfo { Icon = icon, Name = settings.DisplayName, Tooltip = settings.Description ?? settings.DisplayName };
 			var application = new ExternalApplication(executablePath, info, logger.CloneFor(settings.DisplayName), processFactory);
 
 			return application;

SafeExamBrowser.Applications/ExternalApplication.cs

@@ -44,9 +44,11 @@ namespace SafeExamBrowser.Applications
 		{
 			logger.Info("Starting application...");
 
+			// TODO: Ensure that SEB does not crash if an application cannot be started!!
+
 			var process = processFactory.StartNew(executablePath);
 			var id = new ApplicationInstanceIdentifier(process.Id);
-			var instance = new ExternalApplicationInstance(id, logger.CloneFor($"{Info.Name} {id}"), process);
+			var instance = new ExternalApplicationInstance(Info.Icon, id, logger.CloneFor($"{Info.Name} {id}"), process);
 
 			instance.Initialize();
 			instances.Add(instance);

SafeExamBrowser.Applications/ExternalApplicationInstance.cs

@@ -10,6 +10,7 @@ using System;
 using System.Timers;
 using SafeExamBrowser.Applications.Contracts;
 using SafeExamBrowser.Applications.Contracts.Events;
+using SafeExamBrowser.Core.Contracts;
 using SafeExamBrowser.Logging.Contracts;
 using SafeExamBrowser.WindowsApi.Contracts;
 
@@ -24,6 +25,7 @@ namespace SafeExamBrowser.Applications
 		private IProcess process;
 		private Timer timer;
 
+		public IconResource Icon { get; }
 		public InstanceIdentifier Id { get; }
 		public string Name { get; }
 
@@ -31,8 +33,9 @@ namespace SafeExamBrowser.Applications
 		public event NameChangedEventHandler NameChanged;
 		public event InstanceTerminatedEventHandler Terminated;
 
-		public ExternalApplicationInstance(InstanceIdentifier id, ILogger logger, IProcess process)
+		public ExternalApplicationInstance(IconResource icon, InstanceIdentifier id, ILogger logger, IProcess process)
 		{
+			this.Icon = icon;
 			this.Id = id;
 			this.logger = logger;
 			this.process = process;

SafeExamBrowser.Browser/BrowserApplication.cs

@@ -65,7 +65,7 @@ namespace SafeExamBrowser.Browser
 			var cefSettings = InitializeCefSettings();
 			var success = Cef.Initialize(cefSettings, true, default(IApp));
 
-			Info = BuildApplicationInfo();
+			InitializeApplicationInfo();
 
 			if (success)
 			{
@@ -95,11 +95,11 @@ namespace SafeExamBrowser.Browser
 			logger.Info("Terminated browser.");
 		}
 
-		private ApplicationInfo BuildApplicationInfo()
+		private void InitializeApplicationInfo()
 		{
-			return new ApplicationInfo
+			Info = new ApplicationInfo
 			{
-				IconResource = new BrowserIconResource(),
+				Icon = new BrowserIconResource(),
 				Name = "Safe Exam Browser",
 				Tooltip = text.Get(TextKey.Browser_Tooltip)
 			};

SafeExamBrowser.Browser/BrowserApplicationInstance.cs

@@ -17,6 +17,7 @@ using SafeExamBrowser.Browser.Events;
 using SafeExamBrowser.Browser.Filters;
 using SafeExamBrowser.Browser.Handlers;
 using SafeExamBrowser.Configuration.Contracts;
+using SafeExamBrowser.Core.Contracts;
 using SafeExamBrowser.I18n.Contracts;
 using SafeExamBrowser.Logging.Contracts;
 using SafeExamBrowser.Settings.Browser;
@@ -48,6 +49,7 @@ namespace SafeExamBrowser.Browser
 			get { return isMainInstance ? settings.MainWindow : settings.AdditionalWindow; }
 		}
 
+		public IconResource Icon { get; private set; }
 		public InstanceIdentifier Id { get; private set; }
 		public string Name { get; private set; }
 
@@ -108,6 +110,8 @@ namespace SafeExamBrowser.Browser
 			var requestLogger = logger.CloneFor($"{nameof(RequestHandler)} {Id}");
 			var requestHandler = new RequestHandler(appConfig, settings.Filter, requestFilter, requestLogger, text);
 
+			Icon = new BrowserIconResource();
+
 			displayHandler.FaviconChanged += DisplayHandler_FaviconChanged;
 			displayHandler.ProgressChanged += DisplayHandler_ProgressChanged;
 			downloadHandler.ConfigurationDownloadRequested += DownloadHandler_ConfigurationDownloadRequested;
@@ -201,10 +205,10 @@ namespace SafeExamBrowser.Browser
 			{
 				if (task.IsCompleted && task.Result.IsSuccessStatusCode)
 				{
-					var icon = new BrowserIconResource(uri);
+					Icon = new BrowserIconResource(uri);
 
-					IconChanged?.Invoke(icon);
+					IconChanged?.Invoke(Icon);
-					window.UpdateIcon(icon);
+					window.UpdateIcon(Icon);
 				}
 			});
 		}

SafeExamBrowser.Client.UnitTests/Operations/ShellOperationTests.cs

@@ -98,14 +98,12 @@ namespace SafeExamBrowser.Client.UnitTests.Operations
 			var terminationActivator = new Mock<ITerminationActivator>();
 
 			context.Activators.Add(actionCenterActivator.Object);
-			context.Activators.Add(taskViewActivator.Object);
 			context.Activators.Add(terminationActivator.Object);
 			context.Settings.ActionCenter.EnableActionCenter = true;
 			
 			sut.Perform();
 
 			actionCenterActivator.Verify(a => a.Start(), Times.Once);
-			taskViewActivator.Verify(a => a.Start(), Times.Once);
 			terminationActivator.Verify(a => a.Start(), Times.Once);
 		}
 
@@ -176,6 +174,7 @@ namespace SafeExamBrowser.Client.UnitTests.Operations
 		[TestMethod]
 		public void Perform_MustInitializeTaskView()
 		{
+			// Only start activator if ALT+TAB enabled!
 			Assert.Fail("TODO");
 		}
 

SafeExamBrowser.Client/Operations/ShellOperation.cs

@@ -113,7 +113,7 @@ namespace SafeExamBrowser.Client.Operations
 					actionCenterActivator.Start();
 				}
 
-				if (activator is ITaskViewActivator taskViewActivator)
+				if (Context.Settings.Keyboard.AllowAltTab && activator is ITaskViewActivator taskViewActivator)
 				{
 					taskView.Register(taskViewActivator);
 					taskViewActivator.Start();

SafeExamBrowser.UserInterface.Contracts/Shell/ITaskViewActivator.cs

@@ -16,13 +16,18 @@ namespace SafeExamBrowser.UserInterface.Contracts.Shell
 	public interface ITaskViewActivator : IActivator
 	{
 		/// <summary>
-		/// Fired when the next application instance should be selected.
+		/// Fired when the task view should be hidden.
 		/// </summary>
-		event ActivatorEventHandler Next;
+		event ActivatorEventHandler Deactivated;
 
 		/// <summary>
-		/// Fired when the previous application instance should be selected.
+		/// Fired when the task view should be made visible and the next application instance should be selected.
 		/// </summary>
-		event ActivatorEventHandler Previous;
+		event ActivatorEventHandler NextActivated;
+
+		/// <summary>
+		/// Fired when the task view should be made visible and the previous application instance should be selected.
+		/// </summary>
+		event ActivatorEventHandler PreviousActivated;
 	}
 }

SafeExamBrowser.UserInterface.Desktop/Controls/ActionCenterApplicationButton.xaml.cs

@@ -32,7 +32,7 @@ namespace SafeExamBrowser.UserInterface.Desktop.Controls
 
 		private void InitializeApplicationInstanceButton()
 		{
-			Icon.Content = IconResourceLoader.Load(info.IconResource);
+			Icon.Content = IconResourceLoader.Load(info.Icon);
 			Text.Text = instance?.Name ?? info.Name;
 			Button.Click += (o, args) => Clicked?.Invoke(this, EventArgs.Empty);
 			Button.ToolTip = instance?.Name ?? info.Tooltip;

SafeExamBrowser.UserInterface.Desktop/Controls/TaskbarApplicationControl.xaml.cs

@@ -37,7 +37,7 @@ namespace SafeExamBrowser.UserInterface.Desktop.Controls
 			application.InstanceStarted += Application_InstanceStarted;
 
 			Button.Click += Button_Click;
-			Button.Content = IconResourceLoader.Load(application.Info.IconResource);
+			Button.Content = IconResourceLoader.Load(application.Info.Icon);
 			Button.MouseEnter += (o, args) => InstancePopup.IsOpen = InstanceStackPanel.Children.Count > 1;
 			Button.MouseLeave += (o, args) => Task.Delay(250).ContinueWith(_ => Dispatcher.Invoke(() => InstancePopup.IsOpen = InstancePopup.IsMouseOver));
 			Button.ToolTip = application.Info.Tooltip;

SafeExamBrowser.UserInterface.Desktop/Controls/TaskbarApplicationInstanceButton.xaml.cs

@@ -32,7 +32,7 @@ namespace SafeExamBrowser.UserInterface.Desktop.Controls
 		{
 			Button.Click += Button_Click;
 			Button.ToolTip = instance.Name;
-			Icon.Content = IconResourceLoader.Load(info.IconResource);
+			Icon.Content = IconResourceLoader.Load(info.Icon);
 			instance.IconChanged += Instance_IconChanged;
 			instance.NameChanged += Instance_NameChanged;
 			Text.Text = instance.Name;

SafeExamBrowser.UserInterface.Desktop/TaskView.xaml

@@ -4,9 +4,9 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:local="clr-namespace:SafeExamBrowser.UserInterface.Desktop"
-        mc:Ignorable="d" AllowsTransparency="True" Background="#74000000" BorderBrush="DodgerBlue" BorderThickness="1" Title="TaskView"
+        mc:Ignorable="d" AllowsTransparency="True" Background="#AA000000" BorderBrush="DodgerBlue" BorderThickness="1" Title="TaskView"
-        Height="450" Width="800" WindowStartupLocation="CenterScreen" WindowStyle="None">
+        Topmost="True" Height="450" SizeToContent="WidthAndHeight" Width="800" WindowStartupLocation="CenterScreen" WindowStyle="None">
     <Grid>
-        
+        <StackPanel Name="Rows" Margin="10" Orientation="Vertical" />
     </Grid>
 </Window>

SafeExamBrowser.UserInterface.Desktop/TaskView.xaml.cs

@@ -6,27 +6,156 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
+using System;
+using System.Collections.Generic;
+using System.Linq;
 using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Documents;
+using System.Windows.Media;
 using SafeExamBrowser.Applications.Contracts;
+using SafeExamBrowser.Core.Contracts;
 using SafeExamBrowser.UserInterface.Contracts.Shell;
+using SafeExamBrowser.UserInterface.Shared.Utilities;
 
 namespace SafeExamBrowser.UserInterface.Desktop
 {
 	public partial class TaskView : Window, ITaskView
 	{
+		private IList<IApplicationInstance> instances;
+
 		public TaskView()
 		{
 			InitializeComponent();
+			instances = new List<IApplicationInstance>();
 		}
 
 		public void Add(IApplication application)
 		{
-			
+			application.InstanceStarted += Application_InstanceStarted;
 		}
 
 		public void Register(ITaskViewActivator activator)
 		{
-			
+			activator.Deactivated += Activator_Deactivated;
+			activator.NextActivated += Activator_Next;
+			activator.PreviousActivated += Activator_Previous;
+		}
+
+		private void Application_InstanceStarted(IApplicationInstance instance)
+		{
+			Dispatcher.InvokeAsync(() =>
+			{
+				instance.IconChanged += Instance_IconChanged;
+				instance.NameChanged += Instance_NameChanged;
+				instance.Terminated += Instance_Terminated;
+
+				instances.Add(instance);
+				Update();
+			});
+		}
+
+		private void Activator_Deactivated()
+		{
+			Dispatcher.InvokeAsync(Hide);
+		}
+
+		private void Activator_Next()
+		{
+			Dispatcher.InvokeAsync(ShowConditional);
+		}
+
+		private void Activator_Previous()
+		{
+			Dispatcher.InvokeAsync(ShowConditional);
+		}
+
+		private void Instance_IconChanged(IconResource icon)
+		{
+			// TODO Dispatcher.InvokeAsync(...);
+		}
+
+		private void Instance_NameChanged(string name)
+		{
+			// TODO Dispatcher.InvokeAsync(...);
+		}
+
+		private void Instance_Terminated(InstanceIdentifier id)
+		{
+			Dispatcher.InvokeAsync(() =>
+			{
+				var instance = instances.FirstOrDefault(i => i.Id == id);
+
+				if (instance != default(IApplicationInstance))
+				{
+					instances.Remove(instance);
+					Update();
+				}
+			});
+		}
+
+		private void ShowConditional()
+		{
+			if (Visibility != Visibility.Visible && instances.Any())
+			{
+				Show();
+			}
+		}
+
+		private void Update()
+		{
+			var max = Math.Ceiling(Math.Sqrt(instances.Count));
+			var stack = new Stack<IApplicationInstance>(instances);
+
+			Rows.Children.Clear();
+
+			for (var rowCount = 0; rowCount < max && stack.Any(); rowCount++)
+			{
+				var row = new StackPanel { Orientation = Orientation.Horizontal, HorizontalAlignment = HorizontalAlignment.Center };
+
+				Rows.Children.Add(row);
+
+				for (var columnIndex = 0; columnIndex < max && stack.Any(); columnIndex++)
+				{
+					var instance = stack.Pop();
+					var control = BuildInstanceControl(instance);
+
+					row.Children.Add(control);
+				}
+			}
+
+			UpdateLayout();
+
+			Left = (SystemParameters.WorkArea.Width - Width) / 2 + SystemParameters.WorkArea.Left;
+			Top = (SystemParameters.WorkArea.Height - Height) / 2 + SystemParameters.WorkArea.Top;
+
+			if (!instances.Any())
+			{
+				Hide();
+			}
+		}
+
+		private UIElement BuildInstanceControl(IApplicationInstance instance)
+		{
+			var border = new Border();
+			var stackPanel = new StackPanel();
+			var icon = IconResourceLoader.Load(instance.Icon);
+
+			border.BorderBrush = Brushes.White;
+			border.BorderThickness = new Thickness(1);
+			border.Height = 150;
+			border.Margin = new Thickness(5);
+			border.Padding = new Thickness(2);
+			border.Width = 250;
+			border.Child = stackPanel;
+
+			stackPanel.HorizontalAlignment = HorizontalAlignment.Center;
+			stackPanel.Orientation = Orientation.Vertical;
+			stackPanel.VerticalAlignment = VerticalAlignment.Center;
+			stackPanel.Children.Add(new ContentControl { Content = icon, MaxWidth = 50 });
+			stackPanel.Children.Add(new TextBlock(new Run($"Instance {instance.Name ?? "NULL"}") { Foreground = Brushes.White, FontWeight = FontWeights.Bold }));
+
+			return border;
 		}
 	}
 }

SafeExamBrowser.UserInterface.Mobile/Controls/ActionCenterApplicationButton.xaml.cs

@@ -32,7 +32,7 @@ namespace SafeExamBrowser.UserInterface.Mobile.Controls
 
 		private void InitializeApplicationInstanceButton()
 		{
-			Icon.Content = IconResourceLoader.Load(info.IconResource);
+			Icon.Content = IconResourceLoader.Load(info.Icon);
 			Text.Text = instance?.Name ?? info.Name;
 			Button.Click += (o, args) => Clicked?.Invoke(this, EventArgs.Empty);
 			Button.ToolTip = instance?.Name ?? info.Tooltip;

SafeExamBrowser.UserInterface.Mobile/Controls/TaskbarApplicationControl.xaml.cs

@@ -37,7 +37,7 @@ namespace SafeExamBrowser.UserInterface.Mobile.Controls
 			application.InstanceStarted += Application_InstanceStarted;
 
 			Button.Click += Button_Click;
-			Button.Content = IconResourceLoader.Load(application.Info.IconResource);
+			Button.Content = IconResourceLoader.Load(application.Info.Icon);
 			Button.MouseEnter += (o, args) => InstancePopup.IsOpen = InstanceStackPanel.Children.Count > 1;
 			Button.MouseLeave += (o, args) => Task.Delay(250).ContinueWith(_ => Dispatcher.Invoke(() => InstancePopup.IsOpen = InstancePopup.IsMouseOver));
 			Button.ToolTip = application.Info.Tooltip;

SafeExamBrowser.UserInterface.Mobile/Controls/TaskbarApplicationInstanceButton.xaml.cs

@@ -32,7 +32,7 @@ namespace SafeExamBrowser.UserInterface.Mobile.Controls
 		{
 			Button.Click += Button_Click;
 			Button.ToolTip = instance.Name;
-			Icon.Content = IconResourceLoader.Load(info.IconResource);
+			Icon.Content = IconResourceLoader.Load(info.Icon);
 			instance.IconChanged += Instance_IconChanged;
 			instance.NameChanged += Instance_NameChanged;
 			Text.Text = instance.Name;

SafeExamBrowser.UserInterface.Shared/Activators/TaskViewKeyboardActivator.cs

@@ -17,10 +17,12 @@ namespace SafeExamBrowser.UserInterface.Shared.Activators
 {
 	public class TaskViewKeyboardActivator : KeyboardActivator, ITaskViewActivator
 	{
+		private bool Activated, BlockActivation, LeftShift, Tab;
 		private ILogger logger;
 
-		public event ActivatorEventHandler Next;
+		public event ActivatorEventHandler Deactivated;
-		public event ActivatorEventHandler Previous;
+		public event ActivatorEventHandler NextActivated;
+		public event ActivatorEventHandler PreviousActivated;
 
 		public TaskViewKeyboardActivator(ILogger logger, INativeMethods nativeMethods) : base(nativeMethods)
 		{
@@ -29,17 +31,82 @@ namespace SafeExamBrowser.UserInterface.Shared.Activators
 
 		public void Pause()
 		{
-			Paused = true;
+			BlockActivation = true;
 		}
 
 		public void Resume()
 		{
-			Paused = false;
+			BlockActivation = false;
 		}
 
 		protected override bool Process(Key key, KeyModifier modifier, KeyState state)
 		{
+			if (IsDeactivation(modifier))
+			{
+				return false;
+			}
+
+			if (IsActivation(key, modifier, state))
+			{
+				return true;
+			}
+
 			return false;
 		}
+
+		private bool IsActivation(Key key, KeyModifier modifier, KeyState state)
+		{
+			var changed = false;
+			var pressed = state == KeyState.Pressed && modifier.HasFlag(KeyModifier.Alt);
+
+			switch (key)
+			{
+				case Key.Tab:
+					changed = Tab != pressed;
+					Tab = pressed;
+					break;
+				case Key.LeftShift:
+					changed = LeftShift != pressed;
+					LeftShift = pressed;
+					break;
+			}
+
+			var isActivation = Tab && changed;
+
+			if (isActivation && !BlockActivation)
+			{
+				Activated = true;
+
+				if (LeftShift)
+				{
+					logger.Debug("Detected sequence for previous instance.");
+					PreviousActivated?.Invoke();
+				}
+				else
+				{
+					logger.Debug("Detected sequence for next instance.");
+					NextActivated?.Invoke();
+				}
+			}
+
+			return isActivation;
+		}
+
+		private bool IsDeactivation(KeyModifier modifier)
+		{
+			var isDeactivation = Activated && !modifier.HasFlag(KeyModifier.Alt);
+
+			if (isDeactivation)
+			{
+				Activated = false;
+				LeftShift = false;
+				Tab = false;
+
+				logger.Debug("Detected deactivation sequence.");
+				Deactivated?.Invoke();
+			}
+
+			return isDeactivation;
+		}
 	}
 }