ProgressGraph.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;
using System.Windows.Controls.Primitives;

namespace Progress
{
    public class ProgressGraph : ContentControl
    {
        private Canvas canvas;
        private Axis axis;
        private Brush brush;
        private Rectangle rectangle;
        private Line line;

        /// <summary>
        /// Initializes a new instance of the <see cref="ProgressGraph"/> class.
        /// </summary>
        public ProgressGraph()
        {
            // Set a default colour for the progress graph
            Color color = Colors.LightGreen;
            color.A = 150;

            this.brush = new SolidColorBrush(color);
            this.axis = new Axis();
            this.canvas = new Canvas();
            this.canvas.ClipToBounds = true;
            this.Content = this.canvas;

            Refresh();
        }

        #region Properties



        #endregion

        /// <inheritdoc />
        protected override void OnRenderSizeChanged(System.Windows.SizeChangedInfo sizeInfo)
        {
            base.OnRenderSizeChanged(sizeInfo);

            this.axis.Height = this.Height;
            this.axis.Width = this.Width;

            this.Refresh();
        }

        private void Refresh()
        {
            try
            {
                this.canvas.Children.Clear();
                this.canvas.Children.Add(this.axis);

                this.rectangle = new Rectangle();
                this.rectangle.Height = this.Height;
                this.rectangle.Width = this.Width;
                this.rectangle.Fill = this.brush;
                this.canvas.Children.Add(this.rectangle);

                this.line = new Line();
                this.line.X1 = 0;
                this.line.X2 = this.Width;
                this.line.Y1 = 10;
                this.line.Y2 = 10;
                this.line.StrokeThickness = 1;
                this.line.SnapsToDevicePixels = true;
                this.line.Stroke = Brushes.Black;
                this.canvas.Children.Add(this.line);
            }
            catch (Exception) { }
        }

        public Double Value
        {
            get
            {
                return this.value;
            }
            set
            {
#warning Need to stop when we hit 100%
                this.value = value;

                this.rectangle.Dispatcher.Invoke(new Action(() =>
                {
                    this.rectangle.Width = (this.Width / 100) * value;
                }));
            }
        }
        private Double value;

        public Double Rate
        {
            get { return this.rate; }
            set
            {
                this.rate = value;
                if (this.rate > this.maxRate)
                    this.maxRate = this.rate;

                this.Dispatcher.Invoke(new Action(() =>
                {
#warning This doesn't correctly max out at 80% which is required to print some text. We'll also need to re-scale the graph :/
                    Double rateValue = ((this.Height * 0.8) / this.maxRate) * this.rate;
                    this.line.Y1 = rateValue;
                    this.line.Y2 = rateValue;
                }));
            }
        }
        private Double rate;
        private Double maxRate;
    }
}