ux: pie-chart

- Use `Brushes.Gray` for `Others` group
- Rename `_lastHoverred` to `_lastHovered`
- Make sure that the last slice uses a different color with the first one

Co-authored-by: JC-Chung <52159296+JC-Chung@users.noreply.github.com>
Signed-off-by: leo <longshuang@msn.cn>

Author: love-linger

src/Views/PieChart.cs

@@ -78,7 +78,7 @@ public override void Render(DrawingContext context)
             base.Render(context);
 
             _arcs.Clear();
-            _lastHoverred = null;
+            _lastHovered = null;
 
             var w = Bounds.Width;
             var h = Bounds.Height;
@@ -122,12 +122,13 @@ public override void Render(DrawingContext context)
             var brushIndex = 0;
             var leftArcs = new List<Arc>();
             var rightArcs = new List<Arc>();
-            foreach (var author in _report.Authors)
+            for (var i = 0; i < _report.Authors.Count; i++)
             {
+                var author = _report.Authors[i];
                 var percent = (double)author.Count / total;
-                var brush = s_brushes[brushIndex];
                 if (percent > 0.01)
                 {
+                    var brush = (i == _report.Authors.Count - 1 && i % s_brushes.Length == 0) ? s_brushes[1] : s_brushes[brushIndex];
                     var sweepAngle = percent * 2 * Math.PI;
                     DrawArc(context, startAngle, sweepAngle, brush);
 
@@ -147,9 +148,9 @@ public override void Render(DrawingContext context)
                 {
                     var sweepAngle = remaining;
                     var count = total - renderedCount;
-                    DrawArc(context, startAngle, sweepAngle, brush);
+                    DrawArc(context, startAngle, sweepAngle, Brushes.Gray);
 
-                    var arc = new Arc(startAngle, sweepAngle, "Others", count, (double)count / total, brush, null);
+                    var arc = new Arc(startAngle, sweepAngle, "Others", count, (double)count / total, Brushes.Gray, null);
                     _arcs.Add(arc);
                     if (arc.IsLeftSide)
                         leftArcs.Add(arc);
@@ -248,7 +249,7 @@ protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs chang
 
             if (change.Property == ReportProperty)
             {
-                _lastHoverred = null;
+                _lastHovered = null;
                 HoveringTip = null;
             }
 
@@ -265,7 +266,7 @@ protected override void OnPointerMoved(PointerEventArgs e)
 
             if (_report == null || _report.Authors.Count == 0)
             {
-                _lastHoverred = null;
+                _lastHovered = null;
                 HoveringTip = null;
                 return;
             }
@@ -274,7 +275,7 @@ protected override void OnPointerMoved(PointerEventArgs e)
             var distance = Math.Sqrt(Math.Pow(pos.X - _center.X, 2) + Math.Pow(pos.Y - _center.Y, 2));
             if (distance > _radius)
             {
-                _lastHoverred = null;
+                _lastHovered = null;
                 HoveringTip = null;
                 return;
             }
@@ -287,32 +288,32 @@ protected override void OnPointerMoved(PointerEventArgs e)
             {
                 if (angle >= arc.StartAngle && angle < arc.EndAngle)
                 {
-                    if (_lastHoverred == arc)
+                    if (_lastHovered == arc)
                         return;
 
-                    _lastHoverred = arc;
+                    _lastHovered = arc;
                     HoveringTip = arc.Tip;
                     return;
                 }
             }
 
-            _lastHoverred = null;
+            _lastHovered = null;
             HoveringTip = null;
         }
 
         protected override void OnPointerPressed(PointerPressedEventArgs e)
         {
             base.OnPointerPressed(e);
 
-            if (_lastHoverred != null)
+            if (_lastHovered != null)
             {
                 var statisticsView = this.FindAncestorOfType<Statistics>();
                 if (statisticsView is { DataContext: ViewModels.Statistics vm })
                 {
-                    if (_lastHoverred.Author == null || _lastHoverred.Author == vm.SelectedAuthor)
+                    if (_lastHovered.Author == null || _lastHovered.Author == vm.SelectedAuthor)
                         vm.ChangeAuthor(null);
                     else
-                        vm.ChangeAuthor(_lastHoverred.Author);
+                        vm.ChangeAuthor(_lastHovered.Author);
                 }
             }
         }
@@ -370,7 +371,7 @@ public Arc(double startAngle, double sweepAngle, string title, int count, double
         private Point _center = new Point(0, 0);
         private double _radius = 0;
         private List<Arc> _arcs = new List<Arc>();
-        private Arc _lastHoverred = null;
+        private Arc _lastHovered = null;
         private PieChartToolTip _hoveringTip = null;
     }
 }