SEBWIN-312: Improved stability and usability of log window.

SafeExamBrowser.Applications/ExternalApplicationInstance.cs

@@ -100,9 +100,6 @@ namespace SafeExamBrowser.Applications
 			var success = process.TryGetWindowTitle(out var title);
 			var hasChanged = name?.Equals(title, StringComparison.Ordinal) != true;
 
-			// TODO: Use this and ensure log window doesn't hang on shutdown (if it is open)!
-			// logger.Warn($"Success: {success} HasChanged: {hasChanged}");
-
 			if (success && hasChanged)
 			{
 				name = title;

SafeExamBrowser.I18n.Contracts/TextKey.cs

@@ -27,6 +27,7 @@ namespace SafeExamBrowser.I18n.Contracts
 		LockScreen_TerminateOption,
 		LockScreen_Title,
 		LockScreen_UnlockButton,
+		LogWindow_AutoScroll,
 		LogWindow_Title,
 		MessageBox_ApplicationAutoTerminationDataLossWarning,
 		MessageBox_ApplicationAutoTerminationQuestion,

SafeExamBrowser.I18n/Text.xml

@@ -39,6 +39,9 @@
     <Entry key="LockScreen_UnlockButton">
         Unlock
     </Entry>
+    <Entry key="LogWindow_AutoScroll">
+        Auto-Scroll
+    </Entry>
     <Entry key="LogWindow_Title">
         Application Log
     </Entry>

SafeExamBrowser.UserInterface.Desktop/LogWindow.xaml

@@ -4,8 +4,8 @@
         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" Title="{Binding Path=WindowTitle}" Background="Black" Height="500" Width="1100" MinHeight="350" MinWidth="350"
+        mc:Ignorable="d" Title="{Binding Path=WindowTitle}" Background="Black" Foreground="White" Height="500" Width="1100" MinHeight="350"
-        WindowStartupLocation="CenterScreen" Icon="./Images/LogNotification.ico">
+        MinWidth="350" WindowStartupLocation="CenterScreen" Icon="./Images/LogNotification.ico">
     <Window.Resources>
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>
@@ -14,7 +14,15 @@
         </ResourceDictionary>
     </Window.Resources>
     <Grid>
-        <ScrollViewer x:Name="ScrollViewer" HorizontalScrollBarVisibility="Auto" Padding="5,5,5,0" VerticalScrollBarVisibility="Auto" Template="{StaticResource SmallBarScrollViewer}">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="*" />
+        </Grid.RowDefinitions>
+        <StackPanel Grid.Row="0" Background="White" Orientation="Horizontal">
+            <CheckBox Cursor="Hand" IsChecked="{Binding AutoScroll}" Margin="5" VerticalContentAlignment="Center" Content="{Binding AutoScrollTitle}" />
+        </StackPanel>
+        <ScrollViewer x:Name="ScrollViewer" Grid.Row="1" HorizontalScrollBarVisibility="Auto" Padding="5,5,5,0" VerticalScrollBarVisibility="Auto"
+                      Template="{StaticResource SmallBarScrollViewer}">
             <TextBlock x:Name="LogContent" FontFamily="Consolas" Foreground="White" />
         </ScrollViewer>
     </Grid>

SafeExamBrowser.UserInterface.Desktop/LogWindow.xaml.cs

@@ -8,6 +8,7 @@
 
 using System.ComponentModel;
 using System.Windows;
+using System.Windows.Input;
 using SafeExamBrowser.I18n.Contracts;
 using SafeExamBrowser.Logging.Contracts;
 using SafeExamBrowser.UserInterface.Contracts.Windows;
@@ -75,6 +76,8 @@ namespace SafeExamBrowser.UserInterface.Desktop
 
 		private void LogWindow_Loaded(object sender, RoutedEventArgs e)
 		{
+			Cursor = Cursors.Wait;
+
 			var log = logger.GetLog();
 
 			foreach (var content in log)
@@ -84,6 +87,8 @@ namespace SafeExamBrowser.UserInterface.Desktop
 
 			logger.Subscribe(model);
 			logger.Debug("Opened log window.");
+
+			Cursor = Cursors.Arrow;
 		}
 
 		private void LogWindow_Closing(object sender, CancelEventArgs e)

SafeExamBrowser.UserInterface.Desktop/ViewModels/LogViewModel.cs

@@ -23,6 +23,8 @@ namespace SafeExamBrowser.UserInterface.Desktop.ViewModels
 		private ScrollViewer scrollViewer;
 		private TextBlock textBlock;
 
+		public bool AutoScroll { get; set; } = true;
+		public string AutoScrollTitle => text.Get(TextKey.LogWindow_AutoScroll);
 		public string WindowTitle => text.Get(TextKey.LogWindow_Title);
 
 		public LogViewModel(IText text, ScrollViewer scrollViewer, TextBlock textBlock)
@@ -45,29 +47,25 @@ namespace SafeExamBrowser.UserInterface.Desktop.ViewModels
 				default:
 					throw new NotImplementedException($"The log window is not yet implemented for log content of type {content.GetType()}!");
 			}
-
-			scrollViewer.Dispatcher.Invoke(scrollViewer.ScrollToEnd);
 		}
 
 		private void AppendLogText(ILogText logText)
 		{
-			textBlock.Dispatcher.Invoke(() =>
+			textBlock.Dispatcher.InvokeAsync(() =>
 			{
 				var isHeader = logText.Text.StartsWith("/* ");
 				var isComment = logText.Text.StartsWith("# ");
 				var brush = isHeader || isComment ? Brushes.LimeGreen : textBlock.Foreground;
+				var fontWeight = isHeader ? FontWeights.Bold : FontWeights.Normal;
 
-				textBlock.Inlines.Add(new Run($"{logText.Text}{Environment.NewLine}")
+				textBlock.Inlines.Add(new Run($"{logText.Text}{Environment.NewLine}") { FontWeight = fontWeight, Foreground = brush });
-				{
+				ScrollToEnd();
-					FontWeight = isHeader ? FontWeights.Bold : FontWeights.Normal,
-					Foreground = brush
-				});
 			});
 		}
 
 		private void AppendLogMessage(ILogMessage message)
 		{
-			textBlock.Dispatcher.Invoke(() =>
+			textBlock.Dispatcher.InvokeAsync(() =>
 			{
 				var date = message.DateTime.ToString("HH:mm:ss.fff");
 				var severity = message.Severity.ToString().ToUpper();
@@ -80,6 +78,7 @@ namespace SafeExamBrowser.UserInterface.Desktop.ViewModels
 
 				textBlock.Inlines.Add(infoRun);
 				textBlock.Inlines.Add(messageRun);
+				ScrollToEnd();
 			});
 		}
 
@@ -97,5 +96,13 @@ namespace SafeExamBrowser.UserInterface.Desktop.ViewModels
 					return Brushes.White;
 			}
 		}
+
+		private void ScrollToEnd()
+		{
+			if (AutoScroll)
+			{
+				scrollViewer.ScrollToEnd();
+			}
+		}
 	}
 }

SafeExamBrowser.UserInterface.Mobile/LogWindow.xaml

@@ -4,8 +4,8 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:local="clr-namespace:SafeExamBrowser.UserInterface.Mobile"
-        mc:Ignorable="d" Title="{Binding Path=WindowTitle}" Background="Black" Height="500" Width="1100" MinHeight="350" MinWidth="350"
+        mc:Ignorable="d" Title="{Binding Path=WindowTitle}" Background="Black" Foreground="White" Height="500" Width="1100" MinHeight="350"
-        WindowState="Maximized" WindowStartupLocation="CenterScreen" Icon="./Images/LogNotification.ico">
+        MinWidth="350" WindowState="Maximized" WindowStartupLocation="CenterScreen" Icon="./Images/LogNotification.ico">
     <Window.Resources>
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>
@@ -14,8 +14,15 @@
         </ResourceDictionary>
     </Window.Resources>
     <Grid>
-        <ScrollViewer x:Name="ScrollViewer" HorizontalScrollBarVisibility="Auto" Padding="5,5,5,0" PanningMode="Both" VerticalScrollBarVisibility="Auto"
+        <Grid.RowDefinitions>
-                      Template="{StaticResource SmallBarScrollViewer}">
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="*" />
+        </Grid.RowDefinitions>
+        <StackPanel Grid.Row="0" Background="White" Orientation="Horizontal">
+            <CheckBox Cursor="Hand" IsChecked="{Binding AutoScroll}" Margin="5" VerticalContentAlignment="Center" Content="{Binding AutoScrollTitle}" />
+        </StackPanel>
+        <ScrollViewer x:Name="ScrollViewer" Grid.Row="1" HorizontalScrollBarVisibility="Auto" Padding="5,5,5,0" PanningMode="Both"
+                      VerticalScrollBarVisibility="Auto" Template="{StaticResource SmallBarScrollViewer}">
             <TextBlock x:Name="LogContent" FontFamily="Consolas" Foreground="White" />
         </ScrollViewer>
     </Grid>

SafeExamBrowser.UserInterface.Mobile/LogWindow.xaml.cs

@@ -8,6 +8,7 @@
 
 using System.ComponentModel;
 using System.Windows;
+using System.Windows.Input;
 using SafeExamBrowser.I18n.Contracts;
 using SafeExamBrowser.Logging.Contracts;
 using SafeExamBrowser.UserInterface.Contracts.Windows;
@@ -75,6 +76,8 @@ namespace SafeExamBrowser.UserInterface.Mobile
 
 		private void LogWindow_Loaded(object sender, RoutedEventArgs e)
 		{
+			Cursor = Cursors.Wait;
+
 			var log = logger.GetLog();
 
 			foreach (var content in log)
@@ -84,6 +87,8 @@ namespace SafeExamBrowser.UserInterface.Mobile
 
 			logger.Subscribe(model);
 			logger.Debug("Opened log window.");
+
+			Cursor = Cursors.Arrow;
 		}
 
 		private void LogWindow_Closing(object sender, CancelEventArgs e)

SafeExamBrowser.UserInterface.Mobile/ViewModels/LogViewModel.cs

@@ -23,6 +23,8 @@ namespace SafeExamBrowser.UserInterface.Mobile.ViewModels
 		private ScrollViewer scrollViewer;
 		private TextBlock textBlock;
 
+		public bool AutoScroll { get; set; } = true;
+		public string AutoScrollTitle => text.Get(TextKey.LogWindow_AutoScroll);
 		public string WindowTitle => text.Get(TextKey.LogWindow_Title);
 
 		public LogViewModel(IText text, ScrollViewer scrollViewer, TextBlock textBlock)
@@ -45,29 +47,25 @@ namespace SafeExamBrowser.UserInterface.Mobile.ViewModels
 				default:
 					throw new NotImplementedException($"The log window is not yet implemented for log content of type {content.GetType()}!");
 			}
-
-			scrollViewer.Dispatcher.Invoke(scrollViewer.ScrollToEnd);
 		}
 
 		private void AppendLogText(ILogText logText)
 		{
-			textBlock.Dispatcher.Invoke(() =>
+			textBlock.Dispatcher.InvokeAsync(() =>
 			{
 				var isHeader = logText.Text.StartsWith("/* ");
 				var isComment = logText.Text.StartsWith("# ");
 				var brush = isHeader || isComment ? Brushes.LimeGreen : textBlock.Foreground;
+				var fontWeight = isHeader ? FontWeights.Bold : FontWeights.Normal;
 
-				textBlock.Inlines.Add(new Run($"{logText.Text}{Environment.NewLine}")
+				textBlock.Inlines.Add(new Run($"{logText.Text}{Environment.NewLine}") { FontWeight = fontWeight, Foreground = brush });
-				{
+				ScrollToEnd();
-					FontWeight = isHeader ? FontWeights.Bold : FontWeights.Normal,
-					Foreground = brush
-				});
 			});
 		}
 
 		private void AppendLogMessage(ILogMessage message)
 		{
-			textBlock.Dispatcher.Invoke(() =>
+			textBlock.Dispatcher.InvokeAsync(() =>
 			{
 				var date = message.DateTime.ToString("HH:mm:ss.fff");
 				var severity = message.Severity.ToString().ToUpper();
@@ -80,6 +78,7 @@ namespace SafeExamBrowser.UserInterface.Mobile.ViewModels
 
 				textBlock.Inlines.Add(infoRun);
 				textBlock.Inlines.Add(messageRun);
+				ScrollToEnd();
 			});
 		}
 
@@ -97,5 +96,13 @@ namespace SafeExamBrowser.UserInterface.Mobile.ViewModels
 					return Brushes.White;
 			}
 		}
+
+		private void ScrollToEnd()
+		{
+			if (AutoScroll)
+			{
+				scrollViewer.ScrollToEnd();
+			}
+		}
 	}
 }