App Icon - Windows App SDK

Question

I've tried this https://github.com/microsoft/microsoft-ui-xaml/issues/4056 but no use.
How do I add an icon for my WinUI 3 Windows App SDK app both in window title bar as well as the taskbar?

Answer 1

For the exe/Taskbar, in Properties :

For the main window, a way :

IntPtr hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);  
string sExe = System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName;  
System.Drawing.Icon ico = System.Drawing.Icon.ExtractAssociatedIcon(sExe);  
SendMessage(hWnd, WM_SETICON, ICON_BIG, ico.Handle);  

with :

public const int ICON_SMALL = 0;  
public const int ICON_BIG = 1;  
public const int ICON_SMALL2 = 2;  
  
public const int WM_GETICON = 0x007F;  
public const int WM_SETICON = 0x0080;  
  
[DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Auto)]  
public static extern int SendMessage(IntPtr hWnd, uint msg, int wParam, IntPtr lParam);  

Answer 2

I had to add in this to get it to show in the title bar - because I am using a hack to modify the title bar when the theme changes. The base code always picks the light theme for the title bar.

    public MainViewModel DataContext { get; set; }
    public MainViewModel ViewModel => DataContext;
    public MainWindow()
    {
        this.InitializeComponent();
        var content = (Content as FrameworkElement)!;
        content.ActualThemeChanged += (s, e) =>
        {
            ModifyTitlebarTheme();
        };
        ModifyTitlebarTheme();

        DataContext = Ioc.Default.GetRequiredService<MainViewModel>();
        ApplicationView.PreferredLaunchViewSize = new Size(1525, 861);
        ApplicationView.PreferredLaunchWindowingMode = ApplicationViewWindowingMode.PreferredLaunchViewSize;

        var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
        var windowId = Win32Interop.GetWindowIdFromWindow(hWnd);
        var appWindow = AppWindow.GetFromWindowId(windowId);
        var size = new Windows.Graphics.SizeInt32();
        size.Width = 1150;
        size.Height = 1200;
        appWindow.Resize(size);

        Microsoft.UI.Windowing.DisplayArea displayArea = Microsoft.UI.Windowing.DisplayArea.GetFromWindowId(windowId, Microsoft.UI.Windowing.DisplayAreaFallback.Nearest);
        if (displayArea is not null)
        {
            var CenteredPosition = appWindow.Position;
            CenteredPosition.X = ((displayArea.WorkArea.Width - appWindow.Size.Width) / 2);
            CenteredPosition.Y = ((displayArea.WorkArea.Height - appWindow.Size.Height) / 2);
            appWindow.Move(CenteredPosition);
        }

        var appSplash = ((App)Application.Current)._splashScreen;
        appSplash?.CenterToScreen(hWnd);
        appSplash?.HideSplash(2);
        appWindow.Title = $"Multi-Site ARC Plus Config Archive Tool";

        hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
        string? sExe = Environment.ProcessPath;
        if (sExe != null)
        {
            System.Drawing.Icon? ico = System.Drawing.Icon.ExtractAssociatedIcon(sExe);
            if (ico != null)
            {
                SendMessage(hWnd, WM_SETICON, ICON_BIG, ico.Handle);
// Had to add these
                SendMessage(hWnd, WM_SETICON, ICON_SMALL, ico.Handle);
                SendMessage(hWnd, WM_SETICON, ICON_SMALL2, ico.Handle);
            }
        }
    }
    private void ModifyTitlebarTheme()
    {
        var content = (Content as FrameworkElement)!;
        var value = content.ActualTheme;

        var titleBar = AppWindow.TitleBar;
        if (value == ElementTheme.Light)
        {
            titleBar.ForegroundColor = Colors.Black;
            titleBar.BackgroundColor = Colors.White;
            titleBar.InactiveForegroundColor = Colors.Gray;
            titleBar.InactiveBackgroundColor = Colors.White;

            titleBar.ButtonForegroundColor = Colors.Black;
            titleBar.ButtonBackgroundColor = Colors.White;
            titleBar.ButtonInactiveForegroundColor = Colors.Gray;
            titleBar.ButtonInactiveBackgroundColor = Colors.White;

            titleBar.ButtonHoverForegroundColor = Colors.Black;
            titleBar.ButtonHoverBackgroundColor = Color.FromArgb(255, 245, 245, 245);
            titleBar.ButtonPressedForegroundColor = Colors.Black;
            titleBar.ButtonPressedBackgroundColor = Colors.White;
        }
        else if (value == ElementTheme.Dark)
        {
            titleBar.ForegroundColor = Colors.White;
            titleBar.BackgroundColor = Color.FromArgb(255, 31, 31, 31);
            titleBar.InactiveForegroundColor = Colors.Gray;
            titleBar.InactiveBackgroundColor = Color.FromArgb(255, 31, 31, 31);

            titleBar.ButtonForegroundColor = Colors.White;
            titleBar.ButtonBackgroundColor = Color.FromArgb(255, 31, 31, 31);
            titleBar.ButtonInactiveForegroundColor = Colors.Gray;
            titleBar.ButtonInactiveBackgroundColor = Color.FromArgb(255, 31, 31, 31);

            titleBar.ButtonHoverForegroundColor = Colors.White;
            titleBar.ButtonHoverBackgroundColor = Color.FromArgb(255, 51, 51, 51);
            titleBar.ButtonPressedForegroundColor = Colors.White;
            titleBar.ButtonPressedBackgroundColor = Colors.Gray;
        }

        // Fixed bug where icon background color was not applied 
        titleBar.IconShowOptions = IconShowOptions.HideIconAndSystemMenu;
        titleBar.IconShowOptions = IconShowOptions.ShowIconAndSystemMenu;
    }