Merge pull request #1112 from github/fixes/resizeable-peek-view

Allow inline comment peek view to resize to content.

Author: grokys

src/GitHub.InlineReviews/Peek/InlineCommentPeekResultPresentation.cs

@@ -6,9 +6,12 @@
 
 namespace GitHub.InlineReviews.Peek
 {
-    class InlineCommentPeekResultPresentation : IPeekResultPresentation
+    class InlineCommentPeekResultPresentation : IPeekResultPresentation, IDesiredHeightProvider
     {
+        const double PeekBorders = 28.0;
         readonly InlineCommentPeekViewModel viewModel;
+        InlineCommentPeekView view;
+        double desiredHeight;
 
         public bool IsDirty => false;
         public bool IsReadOnly => true;
@@ -24,9 +27,23 @@ public double ZoomLevel
             set { }
         }
 
+        public double DesiredHeight
+        {
+            get { return desiredHeight; }
+            private set
+            {
+                if (desiredHeight != value && DesiredHeightChanged != null)
+                {
+                    desiredHeight = value;
+                    DesiredHeightChanged(this, EventArgs.Empty);
+                }
+            }
+        }
+
         public event EventHandler IsDirtyChanged;
         public event EventHandler IsReadOnlyChanged;
         public event EventHandler<RecreateContentEventArgs> RecreateContent;
+        public event EventHandler<EventArgs> DesiredHeightChanged;
 
         public bool CanSave(out string defaultPath)
         {
@@ -45,8 +62,15 @@ public void Close()
 
         public UIElement Create(IPeekSession session, IPeekResultScrollState scrollState)
         {
-            var view = new InlineCommentPeekView();
+            view = new InlineCommentPeekView();
             view.DataContext = viewModel;
+
+            // Report the desired size back to the peek view. Unfortunately the peek view
+            // helpfully assigns this desired size to the control that also contains the tab at
+            // the top of the peek view, so we need to put in a fudge factor. Using a const
+            // value for the moment, as there's no easy way to get the size of the control.
+            view.DesiredHeight.Subscribe(x => DesiredHeight = x + PeekBorders);
+
             return view;
         }
 

src/GitHub.InlineReviews/Services/InlineCommentPeekService.cs

@@ -95,10 +95,15 @@ public ITrackingPoint Show(ITextView textView, AddInlineCommentTag tag)
 
             var line = textView.TextSnapshot.GetLineFromLineNumber(tag.LineNumber);
             var trackingPoint = textView.TextSnapshot.CreateTrackingPoint(line.Start.Position, PointTrackingMode.Positive);
+            var options = new PeekSessionCreationOptions(
+                textView,
+                InlineCommentPeekRelationship.Instance.Name,
+                trackingPoint,
+                defaultHeight: 0);
 
             ExpandCollapsedRegions(textView, line.Extent);
 
-            var session = peekBroker.TriggerPeekSession(textView, trackingPoint, InlineCommentPeekRelationship.Instance.Name);
+            var session = peekBroker.TriggerPeekSession(options);
             var item = session.PeekableItems.OfType<InlineCommentPeekableItem>().FirstOrDefault();
 
             if (item != null)
@@ -133,8 +138,14 @@ public ITrackingPoint Show(ITextView textView, ShowInlineCommentTag tag)
 
             var line = snapshot.GetLineFromLineNumber(tag.LineNumber);
             var trackingPoint = snapshot.CreateTrackingPoint(line.Start.Position, PointTrackingMode.Positive);
+            var options = new PeekSessionCreationOptions(
+                textView,
+                InlineCommentPeekRelationship.Instance.Name,
+                trackingPoint,
+                defaultHeight: 0);
+
             ExpandCollapsedRegions(textView, line.Extent);
-            peekBroker.TriggerPeekSession(textView, trackingPoint, InlineCommentPeekRelationship.Instance.Name);
+            peekBroker.TriggerPeekSession(options);
             return trackingPoint;
         }
 

src/GitHub.InlineReviews/ViewModels/CommentViewModel.cs

@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using System.Linq;
 using System.Reactive;
 using System.Reactive.Linq;
 using System.Threading.Tasks;

src/GitHub.InlineReviews/Views/InlineCommentPeekView.xaml

@@ -78,10 +78,11 @@
             </StackPanel>
         </Border>
 
-        <ScrollViewer VerticalScrollBarVisibility="Auto"
+        <ScrollViewer Name="threadScroller"
+                      VerticalScrollBarVisibility="Auto"
                       Background="#FFF5F5F5">
             <Grid>
-                <local:CommentThreadView DataContext="{Binding Thread}"/>
+                <local:CommentThreadView x:Name="threadView" DataContext="{Binding Thread}"/>
             </Grid>
         </ScrollViewer>
     </DockPanel>

src/GitHub.InlineReviews/Views/InlineCommentPeekView.xaml.cs

@@ -1,25 +1,30 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using System.Windows;
+using System.Reactive.Subjects;
 using System.Windows.Controls;
-using System.Windows.Data;
-using System.Windows.Documents;
-using System.Windows.Input;
-using System.Windows.Media;
-using System.Windows.Media.Imaging;
-using System.Windows.Navigation;
-using System.Windows.Shapes;
+using GitHub.VisualStudio.UI.Helpers;
 
 namespace GitHub.InlineReviews.Views
 {
     public partial class InlineCommentPeekView : UserControl
     {
+        readonly Subject<double> desiredHeight;
+
         public InlineCommentPeekView()
         {
             InitializeComponent();
+
+            desiredHeight = new Subject<double>();
+            threadView.LayoutUpdated += ThreadViewLayoutUpdated;
+            threadScroller.PreviewMouseWheel += ScrollViewerUtilities.FixMouseWheelScroll;
+        }
+
+        public IObservable<double> DesiredHeight => desiredHeight;
+
+        void ThreadViewLayoutUpdated(object sender, EventArgs e)
+        {
+            var otherControlsHeight = ActualHeight - threadScroller.ActualHeight;
+            var threadViewHeight = threadView.DesiredSize.Height + threadView.Margin.Top + threadView.Margin.Bottom;
+            desiredHeight.OnNext(threadViewHeight + otherControlsHeight);
         }
     }
 }

src/GitHub.UI/GitHub.UI.csproj

@@ -90,6 +90,7 @@
     <Compile Include="Helpers\ScrollViewerUtilities.cs" />
     <Compile Include="Helpers\SharedDictionaryManager.cs" />
     <Compile Include="Helpers\TreeViewExtensions.cs" />
+    <Compile Include="Helpers\VisualTreeExtensions.cs" />
     <Compile Include="Resources.Designer.cs">
       <AutoGen>True</AutoGen>
       <DesignTime>True</DesignTime>

src/GitHub.UI/Helpers/ScrollViewerUtilities.cs

@@ -1,5 +1,8 @@
-using System.Windows;
+using System.Linq;
+using System.Windows;
+using System.Windows.Controls;
 using System.Windows.Input;
+using GitHub.UI.Helpers;
 
 namespace GitHub.VisualStudio.UI.Helpers
 {
@@ -15,8 +18,9 @@ public static class ScrollViewerUtilities
         /// <param name="e">The event arguments.</param>
         /// <remarks>
         /// WPF's ScrollViewer is broken in that it doesn't pass scroll events to the parent
-        /// control when it can't scroll any more. Add this method as an event handler to a
-        /// control which has a ScrollViewer in its template to fix this.
+        /// control when it can't scroll any more. Add this method as a PreviewMouseWheel event
+        /// handler to a ScrollViewer or a control which has a ScrollViewer in its template to
+        /// fix this.
         /// </remarks>
         public static void FixMouseWheelScroll(object sender, MouseWheelEventArgs e)
         {
@@ -26,15 +30,24 @@ public static void FixMouseWheelScroll(object sender, MouseWheelEventArgs e)
                 {
                     var control = sender as FrameworkElement;
                     var parent = control.Parent as UIElement;
+                    var scrollViewer = control.GetSelfAndVisualDescendents()
+                        .OfType<ScrollViewer>()
+                        .FirstOrDefault();
 
-                    if (parent != null)
+                    if (scrollViewer != null && parent != null)
                     {
-                        e.Handled = true;
-                        parent.RaiseEvent(new MouseWheelEventArgs(e.MouseDevice, e.Timestamp, e.Delta)
+                        var offset = scrollViewer.ContentVerticalOffset;
+
+                        if ((offset == scrollViewer.ScrollableHeight && e.Delta < 0) ||
+                            (offset == 0 && e.Delta > 0))
                         {
-                            RoutedEvent = UIElement.MouseWheelEvent,
-                            Source = control,
-                        });
+                            e.Handled = true;
+                            parent.RaiseEvent(new MouseWheelEventArgs(e.MouseDevice, e.Timestamp, e.Delta)
+                            {
+                                RoutedEvent = UIElement.MouseWheelEvent,
+                                Source = control,
+                            });
+                        }
                     }
                 }
             }

src/GitHub.UI/Helpers/VisualTreeExtensions.cs

@@ -0,0 +1,57 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Windows.Media;
+using GitHub.Extensions;
+
+namespace GitHub.UI.Helpers
+{
+    public static class VisualTreeExtensions
+    {
+        public static IEnumerable<Visual> GetSelfAndVisualAncestors(this Visual visual)
+        {
+            Guard.ArgumentNotNull(visual, nameof(visual));
+
+            return Enumerable.Repeat(visual, 1).Concat(GetVisualAncestors(visual));
+        }
+
+        public static IEnumerable<Visual> GetVisualAncestors(this Visual visual)
+        {
+            Guard.ArgumentNotNull(visual, nameof(visual));
+
+            while (true)
+            {
+                visual = VisualTreeHelper.GetParent(visual) as Visual;
+
+                if (visual != null)
+                    yield return visual;
+                else
+                    break;
+            }
+        }
+
+        public static IEnumerable<Visual> GetSelfAndVisualDescendents(this Visual visual)
+        {
+            Guard.ArgumentNotNull(visual, nameof(visual));
+
+            return Enumerable.Repeat(visual, 1).Concat(GetVisualDescendents(visual));
+        }
+
+        public static IEnumerable<Visual> GetVisualDescendents(this Visual visual)
+        {
+            Guard.ArgumentNotNull(visual, nameof(visual));
+
+            var count = VisualTreeHelper.GetChildrenCount(visual);
+
+            for (var i = 0; i < count; ++i)
+            {
+                var child = (Visual)VisualTreeHelper.GetChild(visual, i);
+                yield return child;
+
+                foreach (var descendent in child.GetVisualDescendents())
+                {
+                    yield return descendent;
+                }
+            }
+        }
+    }
+}

src/GitHub.VisualStudio/GitHub.VisualStudio.csproj

@@ -287,7 +287,6 @@
       <Link>Properties\SolutionInfo.cs</Link>
     </Compile>
     <Compile Include="AssemblyResolverPackage.cs" />
-    <Compile Include="Helpers\VisualTreeExtensions.cs" />
     <Compile Include="IServiceProviderPackage.cs" />
     <Compile Include="Menus\BlameLink.cs" />
     <Compile Include="Menus\MenuBase.cs" />

src/GitHub.VisualStudio/Helpers/VisualTreeExtensions.cs

@@ -9,22 +9,21 @@
 using System.Windows.Media;
 using GitHub.Exports;
 using GitHub.Extensions;
+using GitHub.InlineReviews.Commands;
 using GitHub.Models;
 using GitHub.Services;
 using GitHub.UI;
+using GitHub.UI.Helpers;
 using GitHub.ViewModels;
-using GitHub.VisualStudio.Helpers;
 using GitHub.VisualStudio.UI.Helpers;
-using Microsoft.VisualStudio.Shell;
 using Microsoft.VisualStudio;
 using Microsoft.VisualStudio.Editor;
+using Microsoft.VisualStudio.Shell;
 using Microsoft.VisualStudio.Shell.Interop;
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor;
 using ReactiveUI;
 using Task = System.Threading.Tasks.Task;
-using GitHub.InlineReviews.Commands;
-using GitHub.UI.Helpers;
 
 namespace GitHub.VisualStudio.UI.Views
 {