Kepler-Release/Venus/Venus_Themes/Converters/RingProgressArcConverter.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;
using System.Windows.Media;
using Venus_Themes.CustomControls;

namespace Venus_Themes.Converters
{
    public class RingProgressArcConverter : IMultiValueConverter
    {
        // 注意,因为这里使用Path绘制圆环, 所以要把描边宽度大小考虑进去. 所有点的x、y偏移 半个描边宽度
        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
        {
            if (values == null) { return null; }
            double value;
            if (values[0] is double width
                && values[1] is double height
                && width > 0 && height > 0
                && values[2] is double storkeWidth)
            {
                width -= storkeWidth;
                height -= storkeWidth;

                value = values.Length == 4 ? System.Convert.ToDouble(values[3]) : 1d;

                if (value == 0) return "";

                var startAngle = -90d;
                var endAngle = Math.Min(value * 360 - 90, 269);
                var radius = Math.Min(width, height) * 0.5;
                var start = startAngle.AngleToPoint(radius, storkeWidth * 0.5);
                var end = endAngle.AngleToPoint(radius, storkeWidth * 0.5);

                var dataStr = $"M {start.X},{start.Y} A {radius},{radius} 0 {(endAngle - startAngle >= 180 ? 1 : 0)} 1 {end.X},{end.Y}";

                var converter = TypeDescriptor.GetConverter(typeof(Geometry));
                return (Geometry)converter.ConvertFrom(dataStr);
            }
            else
            {
                return "";
            }
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}