Vanara/Windows.Shell/TaskBar/ThumbnailToolbarButton.cs

using System;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Design;
using System.Runtime.CompilerServices;
using System.Windows.Forms;
using Vanara.Extensions;
using static Vanara.PInvoke.Shell32;

namespace Vanara.Windows.Shell
{
	/// <summary></summary>
	public enum Visibility : byte
	{
		/// <summary>The collapsed</summary>
		Collapsed = 2,

		/// <summary>The hidden</summary>
		Hidden = 1,

		/// <summary>The visible</summary>
		Visible = 0
	}

	/// <summary>A button in the toolbar associated with thumbnails displayed on a taskbar button.</summary>
	/// <seealso cref="System.ComponentModel.INotifyPropertyChanged"/>
	[DefaultProperty("Description"), DefaultEvent("Click")]
	public partial class ThumbnailToolbarButton : INotifyPropertyChanged
	{
		internal THUMBBUTTON btn;
		internal ImageIndexer indexer = new();
		private Icon icon;
		private ThumbnailToolbar parent;
		private Visibility visibility;

		/// <summary>Initializes a new instance of the <see cref="ThumbnailToolbarButton"/> class.</summary>
		public ThumbnailToolbarButton()
		{
		}

		/// <summary>Occurs when the button is clicked.</summary>
		[Category("Behavior")]
		public event EventHandler Click;

		/// <summary>Occurs when a property has changed.</summary>
		public event PropertyChangedEventHandler PropertyChanged;

		/// <summary>Gets or sets the description displayed as a tooltip for the button.</summary>
		/// <value>The description text.</value>
		[DefaultValue(null), Category("Appearance")]
		public string Description
		{
			get => btn.szTip;
			set { btn.szTip = value; btn.dwMask |= THUMBBUTTONMASK.THB_TOOLTIP; OnPropertyChanged(); }
		}

		/// <summary>Gets or sets a value indicating whether to dismiss the thumbnail when this button is clicked.</summary>
		/// <value><see langword="true"/> to dismiss when clicked; otherwise, <see langword="false"/>.</value>
		[DefaultValue(false), Category("Behavior")]
		public bool DismissWhenClicked
		{
			get => GetFlagValue(THUMBBUTTONFLAGS.THBF_DISMISSONCLICK);
			set => SetFlagValue(THUMBBUTTONFLAGS.THBF_DISMISSONCLICK, value);
		}

		/// <summary>Gets or sets a value indicating whether to draw the button's border.</summary>
		/// <value><see langword="true"/> if button border is drawn; otherwise, <see langword="false"/>.</value>
		[DefaultValue(true), Category("Appearance")]
		public bool DrawButtonBorder
		{
			get => !GetFlagValue(THUMBBUTTONFLAGS.THBF_NOBACKGROUND);
			set => SetFlagValue(THUMBBUTTONFLAGS.THBF_NOBACKGROUND, !value);
		}

		/// <summary>Gets or sets the icon shown on the toolbar button.</summary>
		/// <value>The button icon.</value>
		[Description("ButtonImageDescr"), Localizable(true), Category("Appearance")]
		[DefaultValue(null)]
		public Icon Icon
		{
			get => icon;
			set
			{
				if (icon != value)
				{
					icon = value;
					if (icon != null)
						ImageIndex = -1;
					UpdateImageInfo();
					OnPropertyChanged();
				}
			}
		}

		/// <summary>Gets or sets the index of the image from <see cref="ThumbnailToolbar.ImageList"/>.</summary>
		/// <value>The index of the image.</value>
		/// <exception cref="ArgumentOutOfRangeException">ImageIndex</exception>
		[TypeConverter(typeof(ImageIndexConverter)), Editor("System.Windows.Forms.Design.ImageIndexEditor, System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", typeof(UITypeEditor)), Localizable(true), DefaultValue(-1), RefreshProperties(RefreshProperties.Repaint)]
		[Description("ButtonImageIndexDescr"), Category("Appearance")]
		public int ImageIndex
		{
			get
			{
				if (indexer.Index != -1 && Parent?.ImageList != null && indexer.Index >= Parent.ImageList.Images.Count)
					return Parent.ImageList.Images.Count - 1;
				return indexer.Index;
			}
			set
			{
				if (value < -1)
					throw new ArgumentOutOfRangeException(nameof(ImageIndex));

				if (indexer.Index != value)
				{
					if (value != -1)
						icon = null;
					indexer.Index = value;
					UpdateImageInfo();
					OnPropertyChanged();
				}
			}
		}

		/// <summary>Gets or sets the image key of the image from <see cref="ThumbnailToolbar.ImageList"/>.</summary>
		/// <value>The image key value.</value>
		[TypeConverter(typeof(ImageKeyConverter)), Editor("System.Windows.Forms.Design.ImageIndexEditor, System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", typeof(UITypeEditor)), Localizable(true), DefaultValue(""), RefreshProperties(RefreshProperties.Repaint)]
		[Description("ButtonImageIndexDescr"), Category("Appearance")]
		public string ImageKey
		{
			get => indexer.Key;
			set
			{
				if (indexer.Key != value)
				{
					if (value != null)
						icon = null;
					indexer.Key = value;
					UpdateImageInfo();
					OnPropertyChanged();
				}
			}
		}

		/// <summary>Gets or sets a value indicating whether this button is enabled.</summary>
		/// <value><see langword="true"/> if this button is enabled; otherwise, <see langword="false"/>.</value>
		[DefaultValue(true), Category("Behavior")]
		public bool IsEnabled
		{
			get => !GetFlagValue(THUMBBUTTONFLAGS.THBF_DISABLED);
			set => SetFlagValue(THUMBBUTTONFLAGS.THBF_DISABLED, !value);
		}

		/// <summary>
		/// Gets or sets a value indicating whether this button is interactive. If <see langword="false"/>, no pressed button state is
		/// drawn. This is intended for instances where the button is used in a notification.
		/// </summary>
		/// <value><see langword="true"/> if this button is interactive; otherwise, <see langword="false"/>.</value>
		[DefaultValue(true), Category("Behavior")]
		public bool IsInteractive
		{
			get => !GetFlagValue(THUMBBUTTONFLAGS.THBF_NONINTERACTIVE);
			set => SetFlagValue(THUMBBUTTONFLAGS.THBF_NONINTERACTIVE, !value);
		}

		/// <summary>Gets or sets the visibility of the button.</summary>
		/// <value>The button visibility.</value>
		[DefaultValue(typeof(Visibility), "Visible"), Category("Appearance")]
		public Visibility Visibility
		{
			get => visibility;
			set { if (visibility != value) { visibility = value; OnPropertyChanged(); } }
		}

		internal ThumbnailToolbar Parent
		{
			get => parent;
			set
			{
				parent = value;
				indexer.ImageList = value.ImageList;
			}
		}

		internal void InvokeClick() => Click?.Invoke(this, EventArgs.Empty);

		/// <summary>Called when a property has changed.</summary>
		/// <param name="propName">Name of the property.</param>
		protected virtual void OnPropertyChanged([CallerMemberName] string propName = "") => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName));

		private bool GetFlagValue(THUMBBUTTONFLAGS f) => btn.dwFlags.IsFlagSet(f);

		private void SetFlagValue(THUMBBUTTONFLAGS f, bool value, [CallerMemberName] string memberName = "")
		{
			btn.dwFlags = btn.dwFlags.SetFlags(f, value);
			btn.dwMask |= THUMBBUTTONMASK.THB_FLAGS;
			OnPropertyChanged(memberName);
		}

		private void UpdateImageInfo()
		{
			if (icon == null && indexer.ActualIndex >= 0)
			{
				btn.dwMask |= THUMBBUTTONMASK.THB_ICON | THUMBBUTTONMASK.THB_BITMAP;
				btn.hIcon = IntPtr.Zero;
				btn.iBitmap = (uint)indexer.ActualIndex;
			}
			else
			{
				btn.dwMask |= THUMBBUTTONMASK.THB_ICON | THUMBBUTTONMASK.THB_BITMAP;
				if (icon == null)
					btn.hIcon = IntPtr.Zero;
				else
					btn.hIcon = icon.Handle;
				btn.iBitmap = 0;
			}
		}
	}
}