Merge f7b05b7171 into 3068850405

src/Avalonia.Controls/Primitives/ScrollBar.cs

@@ -247,15 +247,41 @@ namespace Avalonia.Controls.Primitives
 
         protected override void OnKeyDown(KeyEventArgs e)
         {
-            if (e.Key == Key.PageUp)
+            if (Orientation == Orientation.Vertical)
             {
-                LargeDecrement();
-                e.Handled = true;
+                if (e.Key == Key.PageUp)
+                {
+                    LargeDecrement();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.PageDown)
+                {
+                    LargeIncrement();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.Up)
+                {
+                    SmallDecrement();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.Down)
+                {
+                    SmallIncrement();
+                    e.Handled = true;
+                }
             }
-            else if (e.Key == Key.PageDown)
+            else if (Orientation == Orientation.Horizontal)
             {
-                LargeIncrement();
-                e.Handled = true;
+                if (e.Key == Key.Left)
+                {
+                    SmallDecrement();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.Right)
+                {
+                    SmallIncrement();
+                    e.Handled = true;
+                }
             }
         }
 

src/Avalonia.Controls/ScrollViewer.cs

@@ -786,6 +786,29 @@ namespace Avalonia.Controls
                 PageDown();
                 e.Handled = true;
             }
+            else if (e.Source == this)
+            {
+                if (e.Key == Key.Left)
+                {
+                    LineLeft();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.Right)
+                {
+                    LineRight();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.Up)
+                {
+                    LineUp();
+                    e.Handled = true;
+                }
+                else if (e.Key == Key.Down)
+                {
+                    LineDown();
+                    e.Handled = true;
+                }
+            }
         }
 
         /// <summary>