Billing/Billing.Shared/UI/CustomControl.cs

using System;
using Xamarin.Forms;

namespace Billing.UI
{
    public class TintHelper
    {
        public const string TintColor = nameof(TintColor);
        public static readonly BindableProperty TintColorProperty = BindableProperty.CreateAttached(TintColor, typeof(Color?), typeof(TintHelper), null);

        public static void SetTintColor(BindableObject obj, Color? color) => obj.SetValue(TintColorProperty, color);
        public static Color? GetTintColor(BindableObject obj) => (Color?)obj.GetValue(TintColorProperty);
    }

    public class TintImage : Image { }

    public class TintImageButton : ImageButton { }

    public class LongPressButton : Button
    {
        public event EventHandler LongPressed;

        public LongPressButton()
        {
            Padding = 0;
            BackgroundColor = Color.Transparent;
        }

        public void TriggerLongPress()
        {
            LongPressed?.Invoke(this, EventArgs.Empty);
        }
    }

    public class LongPressGrid : Grid
    {
        public static readonly BindableProperty LongCommandProperty = Helper.Create<Command, LongPressGrid>(nameof(LongCommand));
        public static readonly BindableProperty LongCommandParameterProperty = Helper.Create<object, LongPressGrid>(nameof(LongCommandParameter));

        public Command LongCommand
        {
            get => (Command)GetValue(LongCommandProperty);
            set => SetValue(LongCommandProperty, value);
        }
        public object LongCommandParameter
        {
            get => GetValue(LongCommandParameterProperty);
            set => SetValue(LongCommandParameterProperty, value);
        }

        public void TriggerLongPress()
        {
            var command = LongCommand;
            if (command == null)
            {
                return;
            }
            var parameter = LongCommandParameter;
            if (command.CanExecute(parameter))
            {
                command.Execute(parameter);
            }
        }
    }

    public class BlurryPanel : ContentView { }
}