desktop/WirelessTextSyncer.Windows/Tray/TrayIconFactory.cs

using System.Drawing.Imaging;
using System.Reflection;
using System.Runtime.InteropServices;

namespace WirelessTextSyncer.Windows.Tray;

internal static class TrayIconFactory
{
    private const string ConnectedResourceName = "WirelessTextSyncer.TrayConnected.png";
    private const string WaitResourceName = "WirelessTextSyncer.TrayWait.png";

    public static Icon CreateConnectedIcon()
    {
        return CreateIconFromResource(ConnectedResourceName);
    }

    public static Icon CreateWaitIcon()
    {
        return CreateIconFromResource(WaitResourceName);
    }

    private static Icon CreateIconFromResource(string resourceName)
    {
        var assembly = Assembly.GetExecutingAssembly();
        using var stream = assembly.GetManifestResourceStream(resourceName)
            ?? throw new InvalidOperationException($"Tray icon resource not found: {resourceName}");
        using var source = new Bitmap(stream);
        using var bitmap = new Bitmap(source.Width, source.Height, PixelFormat.Format32bppArgb);
        using (var graphics = Graphics.FromImage(bitmap))
        {
            graphics.Clear(Color.Transparent);
            graphics.DrawImage(source, 0, 0, source.Width, source.Height);
        }

        var handle = bitmap.GetHicon();
        try
        {
            using var icon = Icon.FromHandle(handle);
            return (Icon)icon.Clone();
        }
        finally
        {
            DestroyIcon(handle);
        }
    }

    [DllImport("user32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    private static extern bool DestroyIcon(IntPtr handle);
}