maui-linux/Xamarin.Forms.Platform.GTK/Helpers/DialogHelper.cs

using Gtk;
using System.Linq;
using Xamarin.Forms.Internals;
using Xamarin.Forms.Platform.GTK.Extensions;

namespace Xamarin.Forms.Platform.GTK.Helpers
{
	internal static class DialogHelper
	{
		public static void ShowAlert(PlatformRenderer platformRender, AlertArguments arguments)
		{
			MessageDialog messageDialog = new MessageDialog(
					platformRender.Toplevel as Window,
					DialogFlags.DestroyWithParent,
					MessageType.Other,
					GetAlertButtons(arguments),
					arguments.Message);

			SetDialogTitle(arguments.Title, messageDialog);
			SetButtonText(arguments.Accept, ButtonsType.Ok, messageDialog);
			SetButtonText(arguments.Cancel, ButtonsType.Cancel, messageDialog);

			ResponseType result = (ResponseType)messageDialog.Run();

			if (result == ResponseType.Ok)
			{
				arguments.SetResult(true);
			}
			else
			{
				arguments.SetResult(false);
			}

			messageDialog.Destroy();
		}

		public static void ShowActionSheet(PlatformRenderer platformRender, ActionSheetArguments arguments)
		{
			MessageDialog messageDialog = new MessageDialog(
			   platformRender.Toplevel as Window,
			   DialogFlags.DestroyWithParent,
			   MessageType.Other,
			   ButtonsType.Cancel,
			   null);

			SetDialogTitle(arguments.Title, messageDialog);
			SetButtonText(arguments.Cancel, ButtonsType.Cancel, messageDialog);
			SetDestructionButton(arguments.Destruction, messageDialog);
			AddExtraButtons(arguments, messageDialog);

			int result = messageDialog.Run();

			if ((ResponseType)result == ResponseType.Cancel)
			{
				arguments.SetResult(arguments.Cancel);
			}
			else if ((ResponseType)result == ResponseType.Reject)
			{
				arguments.SetResult(arguments.Destruction);
			}

			messageDialog.Destroy();
		}

		private static void SetDialogTitle(string title, MessageDialog messageDialog)
		{
			messageDialog.Title = title ?? string.Empty;
		}

		private static void SetButtonText(string text, ButtonsType type, MessageDialog messageDialog)
		{
			string gtkLabel = string.Empty;

			switch (type)
			{
				case ButtonsType.Ok:
					gtkLabel = "gtk-ok";
					break;
				case ButtonsType.Cancel:
					gtkLabel = "gtk-cancel";
					break;
			}

			var buttonsBox = messageDialog.GetDescendants()
				.OfType<HButtonBox>()
				.FirstOrDefault();

			if (buttonsBox == null) return;

			var targetButton = buttonsBox.GetDescendants()
				.OfType<Gtk.Button>()
				.FirstOrDefault(x => x.Label == gtkLabel);

			if (targetButton == null) return;

			if (string.IsNullOrEmpty(text))
			{
				targetButton.Hide();
			}
			else
			{
				targetButton.Label = text;
			}
		}

		private static void SetDestructionButton(string destruction, MessageDialog messageDialog)
		{
			if (!string.IsNullOrEmpty(destruction))
			{
				var destructionButton =
					messageDialog.AddButton(destruction, ResponseType.Reject) as Gtk.Button;

				var destructionColor = Color.Red.ToGtkColor();
				destructionButton.Child.ModifyFg(StateType.Normal, destructionColor);
				destructionButton.Child.ModifyFg(StateType.Prelight, destructionColor);
				destructionButton.Child.ModifyFg(StateType.Active, destructionColor);
			}
		}

		private static void AddExtraButtons(ActionSheetArguments arguments, MessageDialog messageDialog)
		{
			var vbox = messageDialog.VBox;

			// As we are not showing any message in this dialog, we just 
			// hide default container and avoid it from using space
			vbox.Children[0].Hide();

			if (arguments.Buttons.Any())
			{
				for (int i = 0; i < arguments.Buttons.Count(); i++)
				{
					var button = new Gtk.Button();
					button.Label = arguments.Buttons.ElementAt(i);
					button.Clicked += (o, e) =>
					{
						arguments.SetResult(button.Label);
						messageDialog.Destroy();
					};
					button.Show();

					vbox.PackStart(button, false, false, 0);
				}
			}
		}

		private static ButtonsType GetAlertButtons(AlertArguments arguments)
		{
			bool hasAccept = !string.IsNullOrEmpty(arguments.Accept);
			bool hasCancel = !string.IsNullOrEmpty(arguments.Cancel);

			ButtonsType type = ButtonsType.None;

			if (hasAccept && hasCancel)
			{
				type = ButtonsType.OkCancel;
			}
			else if (hasAccept && !hasCancel)
			{
				type = ButtonsType.Ok;
			}
			else if (!hasAccept && hasCancel)
			{
				type = ButtonsType.Cancel;
			}

			return type;
		}
	}
}