Xamarin Forms-带斜体字体属性的DisplayAlert

我需要显示一个警报，消息的一部分用斜体字显示，另一部分用普通字显示，如下所示：

var title = "Title";
var body = "This part in Italic. This part normal.";
Application.Current.MainPage.DisplayAlert(title, body, "OK");

void PromptRichTextPopup(string title, string richMessage, string normalMessage, Action onOkCallback, Action onCancel = null) {
            var vc = UIKit.UIApplication.SharedApplication.KeyWindow.RootViewController;
            // take top presented view controller
            while (vc.PresentedViewController != null) {
                vc = vc.PresentedViewController;
            }

            var alertvc = UIAlertController.Create(title, string.Empty, UIAlertControllerStyle.Alert);
            var leftAligned = new NSMutableParagraphStyle();
            leftAligned.Alignment = UITextAlignment.Left;

            var colorTitle = new NSAttributedString(str: title, font: UIFont.BoldSystemFontOfSize(18), foregroundColor: Xamarin.Forms.Color.FromHex("#61acad").ToUIColor());

            alertvc.SetValueForKey(colorTitle, new NSString("attributedTitle"));

            var margin = 5f;
            var height = 30f;
            var width = 256f;

            var container = new UIView(new CGRect(margin, margin, width, height * 4));

            var message = new NSMutableAttributedString(str: richMessage, font: UIFont.ItalicSystemFontOfSize(14), foregroundColor: UIColor.Black);
            message.Append(new NSMutableAttributedString(str: " " + normalMessage, font: UIFont.SystemFontOfSize(14), foregroundColor: UIColor.Black));
            var lblText = new UILabel(new CGRect(0, -(height / 2), width, height * 2)) { AttributedText = message };
            lblText.LineBreakMode = UILineBreakMode.WordWrap;
            lblText.Lines = 0;
            container.AddSubview(lblText);

            var cancel = new UIButton(new CGRect(0, height, width / 2, height * 2));
            cancel.SetTitle("NO", UIControlState.Normal);
            cancel.AddTarget((sender, e) => alertvc.DismissViewController(true, null), UIControlEvent.TouchUpInside);
            cancel.SetTitleColor(UIColor.Blue, UIControlState.Normal);
            if (onCancel != null) {
                cancel.AddTarget((sender, e) => {
                    onCancel();
                },
                UIControlEvent.TouchUpInside);
            }
            container.AddSubview(cancel);

            var ok = new UIButton(new CGRect(width / 2, height, width / 2, height * 2));
            ok.SetTitle("YES", UIControlState.Normal);
            Action okAction = async () => {
                ok.Enabled = false;
                await uiHelper.RunBlocking(() => {
                    onOkCallback();
                });
                alertvc.DismissViewController(true, null);
            };
            ok.SetTitleColor(UIColor.Blue, UIControlState.Normal);
            container.AddSubview(ok);
            ok.AddTarget((sender, e) => {
                okAction();
            }, UIControlEvent.TouchUpInside);

            var controller = new UIViewController();
            controller.View.AddSubview(container);
            alertvc.SetValueForKey(controller, new NSString("contentViewController"));
            vc.PresentViewController(alertvc, true, null);
        }

这部分写着：“这部分用斜体”，斜体，另一部分用普通文本

有可能吗？如果是，如何进行

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提前谢谢

您可以尝试使用自定义渲染器来实现（使用自定义视图和渲染器来处理弹出窗口），但

警报传达与状态相关的重要信息 您的应用程序或设备，并经常请求反馈。警报包括 标题、可选消息、一个或多个按钮和可选 用于收集输入的文本字段。除了这些 元素时，警报的视觉外观是静态的，不能更改 定制的

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可能会对您有所帮助。

我最终创建了一个本机警报控制器，如下所示：

var title = "Title";
var body = "This part in Italic. This part normal.";
Application.Current.MainPage.DisplayAlert(title, body, "OK");

void PromptRichTextPopup(string title, string richMessage, string normalMessage, Action onOkCallback, Action onCancel = null) {
            var vc = UIKit.UIApplication.SharedApplication.KeyWindow.RootViewController;
            // take top presented view controller
            while (vc.PresentedViewController != null) {
                vc = vc.PresentedViewController;
            }

            var alertvc = UIAlertController.Create(title, string.Empty, UIAlertControllerStyle.Alert);
            var leftAligned = new NSMutableParagraphStyle();
            leftAligned.Alignment = UITextAlignment.Left;

            var colorTitle = new NSAttributedString(str: title, font: UIFont.BoldSystemFontOfSize(18), foregroundColor: Xamarin.Forms.Color.FromHex("#61acad").ToUIColor());

            alertvc.SetValueForKey(colorTitle, new NSString("attributedTitle"));

            var margin = 5f;
            var height = 30f;
            var width = 256f;

            var container = new UIView(new CGRect(margin, margin, width, height * 4));

            var message = new NSMutableAttributedString(str: richMessage, font: UIFont.ItalicSystemFontOfSize(14), foregroundColor: UIColor.Black);
            message.Append(new NSMutableAttributedString(str: " " + normalMessage, font: UIFont.SystemFontOfSize(14), foregroundColor: UIColor.Black));
            var lblText = new UILabel(new CGRect(0, -(height / 2), width, height * 2)) { AttributedText = message };
            lblText.LineBreakMode = UILineBreakMode.WordWrap;
            lblText.Lines = 0;
            container.AddSubview(lblText);

            var cancel = new UIButton(new CGRect(0, height, width / 2, height * 2));
            cancel.SetTitle("NO", UIControlState.Normal);
            cancel.AddTarget((sender, e) => alertvc.DismissViewController(true, null), UIControlEvent.TouchUpInside);
            cancel.SetTitleColor(UIColor.Blue, UIControlState.Normal);
            if (onCancel != null) {
                cancel.AddTarget((sender, e) => {
                    onCancel();
                },
                UIControlEvent.TouchUpInside);
            }
            container.AddSubview(cancel);

            var ok = new UIButton(new CGRect(width / 2, height, width / 2, height * 2));
            ok.SetTitle("YES", UIControlState.Normal);
            Action okAction = async () => {
                ok.Enabled = false;
                await uiHelper.RunBlocking(() => {
                    onOkCallback();
                });
                alertvc.DismissViewController(true, null);
            };
            ok.SetTitleColor(UIColor.Blue, UIControlState.Normal);
            container.AddSubview(ok);
            ok.AddTarget((sender, e) => {
                okAction();
            }, UIControlEvent.TouchUpInside);

            var controller = new UIViewController();
            controller.View.AddSubview(container);
            alertvc.SetValueForKey(controller, new NSString("contentViewController"));
            vc.PresentViewController(alertvc, true, null);
        }

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作为“DisplayAlert”的替代方法，您可能希望使用自定义弹出控件。看看这个：