PropertyEditor.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Gtk;

namespace GeneticSharp.Runner.GtkApp
{
    /// <summary>
    /// A property editor to genetic algorithm operators.
    /// </summary>
    public partial class PropertyEditor : Gtk.Dialog
    {
        #region Fields
        private Type m_objectType;
        private Dictionary<PropertyInfo, Widget> m_widgetMap;
        #endregion

        #region Constructors
        public PropertyEditor(Type objectType, object objectInstance)
        {
            this.Build();
            buttonOk.Clicked += delegate
            {
                BindToObject();
                Destroy();
            };

            buttonCancel.Clicked += delegate
            {
                Destroy();
            };

            m_objectType = objectType;

            if (objectInstance == null || objectInstance.GetType() != objectType)
            {
                ObjectInstance = Activator.CreateInstance(objectType);
            }
            else
            {
                ObjectInstance = objectInstance;
            }

            m_widgetMap = new Dictionary<PropertyInfo, Widget>();
            BindToWidget();
            VBox.ResizeMode = ResizeMode.Immediate;
            VBox.CheckResize();

            ShowAll();
        }
        #endregion

        #region Properties
        public object ObjectInstance { get; private set; }
        #endregion

        #region Methods
        public static bool HasEditableProperties(Type objectType)
        {
            return GetObjectProperties(objectType).Length > 0;
        }

        private static PropertyInfo[] GetObjectProperties(Type objectType)
        {
            return objectType.GetProperties(BindingFlags.Instance | BindingFlags.Public | BindingFlags.DeclaredOnly).Where(p => p.CanWrite).ToArray();
        }

        private void BindToWidget()
        {
            foreach (var p in GetObjectProperties(m_objectType))
            {
                var hbox = new HBox();

                var label = new Label(p.Name);
                hbox.Add(label);
                var value = p.GetValue(ObjectInstance, null);
                Widget input = null;

                if (p.PropertyType == typeof(int))
                {
                    var spinButton = new SpinButton(0, int.MaxValue, 1);
                    spinButton.Value = Convert.ToDouble(value);
                    input = spinButton;
                }

                if (p.PropertyType == typeof(bool))
                {
                    var toggle = new ToggleButton();
                    toggle.Active = Convert.ToBoolean(value);
                    input = toggle;
                }
                else if (p.PropertyType == typeof(float) || p.PropertyType == typeof(double))
                {
                    var horizontalScale = new HScale(0, 1, 0.05);

                    if (ObjectInstance != null)
                    {
                        horizontalScale.Value = Convert.ToDouble(value);
                    }

                    input = horizontalScale;
                }
                else if (p.PropertyType == typeof(TimeSpan))
                {
                    var secondsHBox = new HBox();
                    var seconds = new SpinButton(0, int.MaxValue, 1);
                    seconds.Value = ((TimeSpan)value).TotalSeconds;
                    secondsHBox.Add(seconds);

                    var secondsLabel = new Label("seconds");
                    secondsHBox.Add(secondsLabel);

                    input = secondsHBox;
                }

                if (input != null)
                {
                    m_widgetMap.Add(p, input);
                    hbox.Add(input);
                }

                VBox.Add(hbox);
            }
        }

        private void BindToObject()
        {
            foreach (var m in m_widgetMap)
            {
                if (m.Key.PropertyType == typeof(int))
                {
                    m.Key.SetValue(ObjectInstance, ((SpinButton)m.Value).ValueAsInt, new object[0]);
                }
                else if (m.Key.PropertyType == typeof(bool))
                {
                    m.Key.SetValue(ObjectInstance, ((ToggleButton)m.Value).Active, new object[0]);
                }
                else if (m.Key.PropertyType == typeof(float))
                {
                    m.Key.SetValue(ObjectInstance, Convert.ToSingle(((HScale)m.Value).Value), new object[0]);
                }
                else if (m.Key.PropertyType == typeof(double))
                {
                    m.Key.SetValue(ObjectInstance, ((HScale)m.Value).Value, new object[0]);
                }
                else if (m.Key.PropertyType == typeof(TimeSpan))
                {
                    var hbox = (HBox)m.Value;
                    var seconds = ((SpinButton)hbox.Children[0]).Value;
                    m.Key.SetValue(ObjectInstance, TimeSpan.FromSeconds(seconds), new object[0]);
                }
            }
        }
        #endregion
    }
}