Scrolling scenario upgraded

Terminal.Gui/View/View.ScrollBars.cs

@@ -43,10 +43,15 @@ public partial class View
                                                 Bottom = scrollBar.Visible ? Padding.Thickness.Bottom + 1 : 0
                                             };
 
-                                            scrollBar.SliderPositionChanged += (_, args) =>
-                                            {
-                                                Viewport = Viewport with { X = args.CurrentValue };
-                                            };
+                                            scrollBar.ContentPositionChanged += (_, args) =>
+                                                                                {
+                                                                                    Viewport = Viewport with
+                                                                                    {
+                                                                                        X = Math.Min (
+                                                                                                      args.CurrentValue,
+                                                                                                      GetContentSize ().Width - (Viewport.Width))
+                                                                                    };
+                                                                                };
 
                                             scrollBar.VisibleChanged += (_, _) =>
                                             {
@@ -96,18 +101,23 @@ public partial class View
                                                   Right = scrollBar.Visible ? Padding.Thickness.Right + 1 : 0
                                               };
 
-                                              scrollBar.SliderPositionChanged += (_, args) =>
-                                                                           {
-                                                                               Viewport = Viewport with { Y = args.CurrentValue };
-                                                                           };
+                                              scrollBar.ContentPositionChanged += (_, args) =>
+                                                                                  {
+                                                                                      Viewport = Viewport with
+                                                                                      {
+                                                                                          Y = Math.Min (
+                                                                                                        args.CurrentValue,
+                                                                                                        GetContentSize ().Height - (Viewport.Height))
+                                                                                      };
+                                                                                  };
 
                                               scrollBar.VisibleChanged += (_, _) =>
                                                                           {
                                                                               Padding.Thickness = Padding.Thickness with
                                                                               {
                                                                                   Right = scrollBar.Visible
-                                                                                      ? Padding.Thickness.Right + 1
-                                                                                      : Padding.Thickness.Right - 1
+                                                                                              ? Padding.Thickness.Right + 1
+                                                                                              : Padding.Thickness.Right - 1
                                                                               };
                                                                           };
                                           }
@@ -120,12 +130,12 @@ public partial class View
         {
             if (_verticalScrollBar.IsValueCreated)
             {
-                _verticalScrollBar.Value.SliderPosition = Viewport.Y;
+                _verticalScrollBar.Value.ContentPosition = Viewport.Y;
             }
 
             if (_horizontalScrollBar.IsValueCreated)
             {
-                _horizontalScrollBar.Value.SliderPosition = Viewport.X;
+                _horizontalScrollBar.Value.ContentPosition = Viewport.X;
             }
         };
 

Terminal.Gui/Views/Scroll/Scroll.cs

@@ -159,7 +159,7 @@ public class Scroll : View, IOrientation, IDesignable
     {
         int currentSliderPosition = CalculateSliderPosition (_contentPosition);
 
-        if (newSliderPosition > Size - ViewportDimension || currentSliderPosition == newSliderPosition)
+        if (/*newSliderPosition > Size - ViewportDimension ||*/ currentSliderPosition == newSliderPosition)
         {
             return;
         }

UICatalog/Scenarios/ContentScrolling.cs

@@ -125,7 +125,7 @@ public class ContentScrolling : Scenario
         app.Add (view);
 
         // Add Scroll Setting UI to Padding
-        view.Padding.Thickness = view.Padding.Thickness with { Top = view.Padding.Thickness.Top + 4 };
+        view.Padding.Thickness = view.Padding.Thickness with { Top = view.Padding.Thickness.Top + 6 };
         view.Padding.CanFocus = true;
 
         Label frameLabel = new ()

UICatalog/Scenarios/Scrolling.cs

@@ -3,35 +3,25 @@ using Terminal.Gui;
 
 namespace UICatalog.Scenarios;
 
-[ScenarioMetadata ("Scrolling", "Demonstrates scrolling etc...")]
+[ScenarioMetadata ("Scrolling", "Content scrolling, IScrollBars, etc...")]
 [ScenarioCategory ("Controls")]
 [ScenarioCategory ("Scrolling")]
 [ScenarioCategory ("Tests")]
 public class Scrolling : Scenario
 {
-    private ViewDiagnosticFlags _diagnosticFlags;
-
     public override void Main ()
     {
         Application.Init ();
-        _diagnosticFlags = View.Diagnostics;
-        View.Diagnostics = ViewDiagnosticFlags.Ruler;
 
         var app = new Window
         {
             Title = GetQuitKeyAndName (),
-
-            // Offset to stress clipping
-            X = 3,
-            Y = 3,
-            Width = Dim.Fill (3),
-            Height = Dim.Fill (3)
         };
 
         var label = new Label { X = 0, Y = 0 };
         app.Add (label);
 
-        var scrollView = new ScrollView
+        var scrollView = new IScrollView
         {
             Id = "scrollView",
             X = 2,
@@ -39,53 +29,48 @@ public class Scrolling : Scenario
             Width = 60,
             Height = 20,
             ColorScheme = Colors.ColorSchemes ["TopLevel"],
-
-            //ContentOffset = Point.Empty,
-            ShowVerticalScrollIndicator = true,
-            ShowHorizontalScrollIndicator = true
+            CanFocus = true,
+            BorderStyle = LineStyle.Heavy,
+            Arrangement = ViewArrangement.Resizable
         };
-        // BUGBUG: set_ContentSize is supposed to be `protected`. 
-        scrollView.SetContentSize (new (120, 40));
-        scrollView.Padding.Thickness = new (1);
-
-        label.Text = $"{scrollView}\nContentSize: {scrollView.GetContentSize ()}\nContentOffset: {scrollView.ContentOffset}";
+        scrollView.SetContentSize (new (80, 25));
+        //scrollView.Padding.Thickness = new (1);
+        //scrollView.Padding.Diagnostics = ViewDiagnosticFlags.Ruler;
 
-        const string rule = "0123456789";
-
-        var horizontalRuler = new Label
+        View rulerView = new View ()
         {
-            X = 0,
-            Y = 0,
-
+            Height = Dim.Fill (),
             Width = Dim.Fill (),
-            Height = 2,
-            ColorScheme = Colors.ColorSchemes ["Error"]
         };
-        scrollView.Add (horizontalRuler);
-
-        const string vrule = "0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n";
-
-        var verticalRuler = new Label
+        rulerView.Border.Thickness = new (1);
+        rulerView.Border.LineStyle = LineStyle.None;
+        rulerView.Border.Diagnostics = ViewDiagnosticFlags.Ruler;
+        rulerView.Border.ColorScheme = Colors.ColorSchemes ["Error"];
+
+        scrollView.Add (rulerView);
+        label.Text =
+            $"{scrollView}\nContentSize: {scrollView.GetContentSize ()}\nViewport.Location: {scrollView.Viewport.Location}";
+
+        scrollView.ViewportChanged += (_, _) =>
+                                      {
+                                          label.Text =
+                                              $"{scrollView}\nContentSize: {scrollView.GetContentSize ()}\nViewport.Location: {scrollView.Viewport.Location}";
+                                      };
+
+        var pressMeButton = new Button
         {
-            X = 0,
-            Y = 0,
-
-            Width = 1,
-            Height = Dim.Fill (),
-            ColorScheme = Colors.ColorSchemes ["Error"]
+            X = 1,
+            Y = 1,
+            Text = "Press me!"
         };
-        scrollView.Add (verticalRuler);
-
-        var pressMeButton = new Button { X = 3, Y = 3, Text = "Press me!" };
         pressMeButton.Accepting += (s, e) => MessageBox.Query (20, 7, "MessageBox", "Neat?", "Yes", "No");
         scrollView.Add (pressMeButton);
 
         var aLongButton = new Button
         {
-            X = 3,
-            Y = 4,
+            X = Pos.Right (pressMeButton),
+            Y = Pos.Bottom (pressMeButton),
 
-            Width = Dim.Fill (3),
             Text = "A very long button. Should be wide enough to demo clipping!"
         };
         aLongButton.Accepting += (s, e) => MessageBox.Query (20, 7, "MessageBox", "Neat?", "Yes", "No");
@@ -94,8 +79,8 @@ public class Scrolling : Scenario
         scrollView.Add (
                         new TextField
                         {
-                            X = 3,
-                            Y = 5,
+                            X = Pos.Left (pressMeButton),
+                            Y = Pos.Bottom (aLongButton) + 1,
                             Width = 50,
                             ColorScheme = Colors.ColorSchemes ["Dialog"],
                             Text = "This is a test of..."
@@ -105,8 +90,8 @@ public class Scrolling : Scenario
         scrollView.Add (
                         new TextField
                         {
-                            X = 3,
-                            Y = 10,
+                            X = Pos.Left (pressMeButton),
+                            Y = Pos.Bottom (aLongButton) + 3,
                             Width = 50,
                             ColorScheme = Colors.ColorSchemes ["Dialog"],
                             Text = "... the emergency broadcast system."
@@ -116,19 +101,21 @@ public class Scrolling : Scenario
         scrollView.Add (
                         new TextField
                         {
-                            X = 3,
-                            Y = 99,
+                            X = Pos.Left (pressMeButton),
+                            Y = 40,
                             Width = 50,
-                            ColorScheme = Colors.ColorSchemes ["Dialog"],
+                            ColorScheme = Colors.ColorSchemes ["Error"],
                             Text = "Last line"
                         }
                        );
 
         // Demonstrate AnchorEnd - Button is anchored to bottom/right
-        var anchorButton = new Button { Y = Pos.AnchorEnd (0) - 1, Text = "Bottom Right" };
-
-        // TODO: Use Pos.Width instead of (Right-Left) when implemented (#502)
-        anchorButton.X = Pos.AnchorEnd (0) - (Pos.Right (anchorButton) - Pos.Left (anchorButton));
+        var anchorButton = new Button
+        {
+            X = Pos.AnchorEnd (),
+            Y = Pos.AnchorEnd (),
+            Text = "Bottom Right"
+        };
 
         anchorButton.Accepting += (s, e) =>
                                {
@@ -141,74 +128,51 @@ public class Scrolling : Scenario
 
         app.Add (scrollView);
 
+        scrollView.HorizontalScrollBar.Visible = true;
         var hCheckBox = new CheckBox
         {
             X = Pos.X (scrollView),
             Y = Pos.Bottom (scrollView),
             Text = "Horizontal Scrollbar",
-            CheckedState = scrollView.ShowHorizontalScrollIndicator ? CheckState.Checked : CheckState.UnChecked
+            CheckedState = scrollView.HorizontalScrollBar.Visible ? CheckState.Checked : CheckState.UnChecked
         };
         app.Add (hCheckBox);
+        hCheckBox.CheckedStateChanged += (sender, args) =>
+                                         {
+                                             scrollView.HorizontalScrollBar.Visible = args.CurrentValue == CheckState.Checked;
+                                         };
 
+        scrollView.VerticalScrollBar.Visible = true;
         var vCheckBox = new CheckBox
         {
             X = Pos.Right (hCheckBox) + 3,
             Y = Pos.Bottom (scrollView),
             Text = "Vertical Scrollbar",
-            CheckedState = scrollView.ShowVerticalScrollIndicator ? CheckState.Checked : CheckState.UnChecked
+            CheckedState = scrollView.VerticalScrollBar.Visible ? CheckState.Checked : CheckState.UnChecked
         };
         app.Add (vCheckBox);
+        vCheckBox.CheckedStateChanged += (sender, args) =>
+                                         {
+                                             scrollView.VerticalScrollBar.Visible = args.CurrentValue == CheckState.Checked;
+                                         };
 
         var t = "Auto Hide Scrollbars";
 
         var ahCheckBox = new CheckBox
         {
-            X = Pos.Left (scrollView), Y = Pos.Bottom (hCheckBox), Text = t, CheckedState = scrollView.AutoHideScrollBars ? CheckState.Checked : CheckState.UnChecked
-        };
-        var k = "Keep Content Always In Viewport";
-
-        var keepCheckBox = new CheckBox
-        {
-            X = Pos.Left (scrollView), Y = Pos.Bottom (ahCheckBox), Text = k, CheckedState = scrollView.AutoHideScrollBars ? CheckState.Checked : CheckState.UnChecked
+            X = Pos.Left (scrollView), Y = Pos.Bottom (hCheckBox), Text = t,
+            CheckedState = scrollView.HorizontalScrollBar.AutoHide ? CheckState.Checked : CheckState.UnChecked
         };
 
-        hCheckBox.CheckedStateChanging += (s, e) =>
-                             {
-                                 if (ahCheckBox.CheckedState == CheckState.UnChecked)
-                                 {
-                                     scrollView.ShowHorizontalScrollIndicator = e.NewValue == CheckState.Checked;
-                                 }
-                                 else
-                                 {
-                                     hCheckBox.CheckedState = CheckState.Checked;
-                                     MessageBox.Query ("Message", "Disable Auto Hide Scrollbars first.", "Ok");
-                                 }
-                             };
-
-        vCheckBox.CheckedStateChanging += (s, e) =>
-                             {
-                                 if (ahCheckBox.CheckedState == CheckState.UnChecked)
-                                 {
-                                     scrollView.ShowVerticalScrollIndicator = e.NewValue == CheckState.Checked;
-                                 }
-                                 else
-                                 {
-                                     vCheckBox.CheckedState = CheckState.Checked;
-                                     MessageBox.Query ("Message", "Disable Auto Hide Scrollbars first.", "Ok");
-                                 }
-                             };
-
         ahCheckBox.CheckedStateChanging += (s, e) =>
                               {
-                                  scrollView.AutoHideScrollBars = e.NewValue == CheckState.Checked;
+                                  scrollView.HorizontalScrollBar.AutoHide = e.NewValue == CheckState.Checked;
+                                  scrollView.VerticalScrollBar.AutoHide = e.NewValue == CheckState.Checked;
                                   hCheckBox.CheckedState = CheckState.Checked;
                                   vCheckBox.CheckedState = CheckState.Checked;
                               };
         app.Add (ahCheckBox);
 
-        keepCheckBox.CheckedStateChanging += (s, e) => scrollView.KeepContentAlwaysInViewport = e.NewValue == CheckState.Checked;
-        app.Add (keepCheckBox);
-
         var count = 0;
 
         var mousePos = new Label
@@ -238,38 +202,24 @@ public class Scrolling : Scenario
 
         Application.AddTimeout (TimeSpan.FromMilliseconds (300), timer);
 
-        app.Loaded += App_Loaded;
         app.Unloaded += app_Unloaded;
 
+
         Application.Run (app);
-        app.Loaded -= App_Loaded;
         app.Unloaded -= app_Unloaded;
         app.Dispose ();
         Application.Shutdown ();
 
         return;
 
-        // Local functions
-        void App_Loaded (object sender, EventArgs args)
-        {
-            horizontalRuler.Text =
-                rule.Repeat ((int)Math.Ceiling (horizontalRuler.Viewport.Width / (double)rule.Length)) [
-                                                                                                        ..horizontalRuler.Viewport.Width]
-                + "\n"
-                + "|         ".Repeat (
-                                       (int)Math.Ceiling (horizontalRuler.Viewport.Width / (double)rule.Length)
-                                      ) [
-                                         ..horizontalRuler.Viewport.Width];
-
-            verticalRuler.Text =
-                vrule.Repeat ((int)Math.Ceiling (verticalRuler.Viewport.Height * 2 / (double)rule.Length))
-                    [..(verticalRuler.Viewport.Height * 2)];
-        }
-
         void app_Unloaded (object sender, EventArgs args)
         {
-            View.Diagnostics = _diagnosticFlags;
             pulsing = false;
         }
     }
 }
+
+public class IScrollView : View
+{
+
+}