I think you will not be able to put details of a RichText
in DisplayAlert
of Xamarim.
In SOen there is a very similar question, but it was italic, and the answer was to create a custom alert control that supports RichText
(italic + bold).
Transcribing the solution given in this question:
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);
}
Original issue in SOen : Xamarin.Forms - DisplayAlert with Italic font attribute