ScreenshotProtectionManager.cs

using CoreFoundation;
using Plugin.Maui.ScreenSecurity.Handlers;
using UIKit;
 
namespace Plugin.Maui.ScreenSecurity.Platforms.iOS
{
    internal class ScreenshotProtectionManager
    {
        private static UITextField? _secureTextField = null;
 
        internal static void HandleScreenshotProtection(bool enabled, UIWindow? window = null)
        {
            try
            {
                SetScreenshotProtection(enabled, window);
            }
            catch (Exception ex)
            {
                ErrorsHandler.HandleException(nameof(HandleScreenshotProtection), ex);
            }
        }
 
        private static void SetScreenshotProtection(bool preventScreenshot, UIWindow? window)
        {
            DispatchQueue.MainQueue.DispatchAsync(() =>
            {
                try
                {
                    if (window != null)
                    {
                        _secureTextField ??= new()
                        {
                            UserInteractionEnabled = false
                        };
 
                        UIViewController? rootViewController = GetRootPresentedViewController(window);
 
                        rootViewController?.View?.AddSubview(_secureTextField);
                        window.MakeKeyAndVisible();
 
                        window.Layer.SuperLayer?.AddSublayer(_secureTextField.Layer);
 
                        _secureTextField.Layer.Sublayers?[0].AddSublayer(window.Layer);
                    }
 
                    if (_secureTextField != null)
                    {
                        if (preventScreenshot)
                            _secureTextField.SecureTextEntry = preventScreenshot;
                        else
                        {
                            _secureTextField.SecureTextEntry = false;
                            _secureTextField = null;
                        }
                    }
                }
                catch (Exception ex)
                {
                    ErrorsHandler.HandleException(nameof(SetScreenshotProtection), ex);
                }
            });
        }
 
        private static UIViewController? GetRootPresentedViewController(UIWindow window)
        {
            UIViewController? viewController = window.RootViewController;
 
            while (viewController?.PresentedViewController != null)
            {
                viewController = viewController.PresentedViewController;
            }
 
            return viewController;
        }
    }
}