Implemented SystemTrayManager

Author: 0x5bfa

src/Files.App.Storage/Storables/WindowsStorage/SystemTrayManager.cs

@@ -0,0 +1,158 @@
+// Copyright (c) Files Community
+// Licensed under the MIT License.
+
+using System.Runtime.InteropServices;
+using Windows.Win32;
+using Windows.Win32.Foundation;
+using Windows.Win32.UI.Shell;
+using Windows.Win32.UI.WindowsAndMessaging;
+
+namespace Files.App.Storage
+{
+	/// <summary>
+	/// Exposes a manager to create or delete an system tray icon you provide.
+	/// </summary>
+	public unsafe partial class SystemTrayManager : IDisposable
+	{
+		string _szWndClassName = null!;
+		string _szToolTip = null!;
+		HICON _hIcon = default;
+		private Guid _id;
+		private uint _dwCallbackMsgId;
+		Action<uint> _callback = null!;
+
+		private HWND _hWnd = default;
+		private WNDPROC? _wndProc;
+		private bool _isInitialized;
+		private uint _dwTaskbarRestartMsgId;
+		private bool _isShown;
+
+		public void Initialize(string szWndClassName, string szToolTip, HICON hIcon, Guid id, uint dwCallbackMsgId, Action<uint> callback)
+		{
+			_szWndClassName = szWndClassName;
+			_szToolTip = szToolTip;
+			_hIcon = hIcon;
+			_id = id;
+			_dwCallbackMsgId = dwCallbackMsgId;
+			_callback = callback;
+
+			_isInitialized = true;
+		}
+
+		public bool CreateIcon()
+		{
+			// Not expected usage
+			if (!_isInitialized)
+				throw new InvalidOperationException($"{nameof(SystemTrayManager)} is not initialized. Call {nameof(Initialize)}() before using this method.");
+
+			if (_hWnd.IsNull)
+				_hWnd = CreateIconWindow(_szWndClassName);
+
+			NOTIFYICONDATAW data = default;
+			data.cbSize = (uint)sizeof(NOTIFYICONDATAW);
+			data.hWnd = _hWnd;
+			data.uCallbackMessage = _dwCallbackMsgId;
+			data.guidItem = _id;
+			data.hIcon = _hIcon;
+			data.uFlags = NOTIFY_ICON_DATA_FLAGS.NIF_MESSAGE | NOTIFY_ICON_DATA_FLAGS.NIF_ICON | NOTIFY_ICON_DATA_FLAGS.NIF_TIP | NOTIFY_ICON_DATA_FLAGS.NIF_GUID | NOTIFY_ICON_DATA_FLAGS.NIF_SHOWTIP;
+			data.szTip = _szToolTip;
+			data.Anonymous.uVersion = 4u;
+
+			if (_isShown)
+			{
+				return PInvoke.Shell_NotifyIcon(NOTIFY_ICON_MESSAGE.NIM_DELETE, &data);
+			}
+			else
+			{
+				bool fRes = PInvoke.Shell_NotifyIcon(NOTIFY_ICON_MESSAGE.NIM_DELETE, &data);
+				if (!fRes) return false;
+
+				fRes = PInvoke.Shell_NotifyIcon(NOTIFY_ICON_MESSAGE.NIM_ADD, &data);
+				if (!fRes) return false;
+
+				fRes = PInvoke.Shell_NotifyIcon(NOTIFY_ICON_MESSAGE.NIM_SETVERSION, &data);
+				if (!fRes) return false;
+
+				_isShown = true;
+
+				return true;
+			}
+		}
+
+		public bool DeleteIcon()
+		{
+			if (_isShown)
+			{
+				NOTIFYICONDATAW data = default;
+				data.cbSize = (uint)sizeof(NOTIFYICONDATAW);
+				data.hWnd = _hWnd;
+				data.guidItem = _id;
+				data.uFlags = NOTIFY_ICON_DATA_FLAGS.NIF_GUID;
+				data.Anonymous.uVersion = 4u;
+
+				return PInvoke.Shell_NotifyIcon(NOTIFY_ICON_MESSAGE.NIM_DELETE, &data);
+			}
+
+			return true;
+		}
+
+		private HWND CreateIconWindow(string szWndClassName)
+		{
+			fixed (char* pszWndClassName = szWndClassName)
+			{
+				_wndProc ??= new(WndProc);
+
+				WNDCLASSEXW wndClass = default;
+
+				wndClass.cbSize = (uint)sizeof(WNDCLASSEXW);
+				wndClass.style = WNDCLASS_STYLES.CS_DBLCLKS;
+				wndClass.hInstance = PInvoke.GetModuleHandle(default(PCWSTR));
+				wndClass.lpszClassName = pszWndClassName;
+				wndClass.lpfnWndProc = (delegate* unmanaged[Stdcall]<HWND, uint, WPARAM, LPARAM, LRESULT>)
+					Marshal.GetFunctionPointerForDelegate(_wndProc);
+
+				PInvoke.RegisterClassEx(&wndClass);
+
+				_dwTaskbarRestartMsgId = PInvoke.RegisterWindowMessage("TaskbarCreated");
+
+				return PInvoke.CreateWindowEx(
+					WINDOW_EX_STYLE.WS_EX_LEFT, pszWndClassName, default,
+					WINDOW_STYLE.WS_OVERLAPPED, 0, 0, 1, 1, HWND.Null, HMENU.Null, HINSTANCE.Null, null);
+			}
+		}
+
+		private LRESULT WndProc(HWND hWnd, uint uMsg, WPARAM wParam, LPARAM lParam)
+		{
+			if (uMsg == _dwCallbackMsgId)
+			{
+				_callback((uint)(lParam.Value & 0xFFFF));
+
+				return default;
+			}
+			else if (uMsg is PInvoke.WM_DESTROY)
+			{
+				DeleteIcon();
+
+				return default;
+			}
+			else if (uMsg == _dwTaskbarRestartMsgId && _isInitialized)
+			{
+				DeleteIcon();
+				CreateIcon();
+			}
+
+			return PInvoke.DefWindowProc(hWnd, uMsg, wParam, lParam);
+		}
+
+		public void Dispose()
+		{
+			if (!_hWnd.IsNull)
+				PInvoke.DestroyWindow(_hWnd);
+
+			if (!_hIcon.IsNull)
+				PInvoke.DestroyIcon(_hIcon);
+
+			_wndProc = null;
+		}
+	}
+}