private void OnSliceAdded(IPieSlice slice)
{
var labelItem = new PieChartLabelItem
{
Content = slice.Label,
ContentTemplate = LabelTemplate
};
SetZIndex(labelItem, LabelZindex);
_titleItems.Add(slice, labelItem);
InternalChildren.Add(labelItem);
var valueItem = new PieChartValueItem
{
Content = slice.DisplayedValue,
ContentTemplate = ValueTemplate
};
SetZIndex(valueItem, ValueZIndex);
_valueItems.Add(slice, valueItem);
InternalChildren.Add(valueItem);
var sliceItem = new PieChartSliceItem
{
Slice = slice
};
SetZIndex(sliceItem, SliceZIndex);
_sliceItems.Add(slice, sliceItem);
InternalChildren.Add(sliceItem);
}
/// <summary>
/// Arranges the content of a System.Windows.Controls.Canvas element.
/// </summary>
/// <param name="arrangeSize"></param>
/// <returns></returns>
protected override System.Windows.Size ArrangeOverride(System.Windows.Size arrangeSize)
{
var offset = new Vector(arrangeSize.Width / 2, arrangeSize.Height / 2);
if (_slices != null)
{
double radius = Math.Min(arrangeSize.Width / 2, arrangeSize.Height / 2);
double startAngle = 0;
var fullCircle = new Circle {
Radius = radius
};
double minimumArcAngle = MinimumArcLength / fullCircle.Circumference * 2 * Math.PI;
foreach (IPieSlice slice in _slices)
{
PieChartSliceItem item = _sliceItems[slice];
double relativeValue = item.Slice.Value / SumOfSlices;
double openAngle = Math.Max(relativeValue * 2 * Math.PI, minimumArcAngle);
item.Center = (Point)offset;
item.StartAngle = startAngle;
item.OpenAngle = openAngle;
item.Radius = radius;
item.Arrange(new Rect(0, 0, arrangeSize.Width, arrangeSize.Height));
startAngle += openAngle;
}
}
foreach (var pair in _valueItems)
{
IPieSlice slice = pair.Key;
PieChartValueItem item = pair.Value;
PieChartSliceItem sliceItem = _sliceItems[slice];
System.Windows.Size desiredSize = item.DesiredSize;
Rect rect = FindValuePosition(sliceItem.Shape, desiredSize);
if (sliceItem.Shape.Contains(rect))
{
item.Visibility = Visibility.Visible;
item.Arrange(rect);
}
else
{
item.Visibility = Visibility.Collapsed;
}
}
foreach (var pair in _titleItems)
{
IPieSlice slice = pair.Key;
PieChartLabelItem item = pair.Value;
PieChartSliceItem sliceItem = _sliceItems[slice];
System.Windows.Size desiredSize = item.DesiredSize;
Vector specificOffset;
switch (sliceItem.Direction)
{
case SliceDirection.TopRight:
specificOffset = new Vector(0, -desiredSize.Height);
break;
case SliceDirection.BottomRight:
specificOffset = new Vector(0, 0);
break;
case SliceDirection.BottomLeft:
specificOffset = new Vector(-desiredSize.Width, 0);
break;
default:
specificOffset = new Vector(-desiredSize.Width, -desiredSize.Height);
break;
}
Circle circle = sliceItem.Shape.Circle;
circle.Radius += LabelMargin;
Point position = circle.GetPoint(sliceItem.Angle) + specificOffset;
var rect = new Rect(position, desiredSize);
item.Arrange(rect);
}
return(arrangeSize);
}