Billing/Billing.Shared/UI/CustomControl.cs

using System;
using Xamarin.Forms;

namespace Billing.UI
{
    public class TintImage : Image
    {
        public static readonly BindableProperty PrimaryColorProperty = BindableProperty.Create(nameof(PrimaryColor), typeof(Color?), typeof(TintImage));

        public Color? PrimaryColor
        {
            get => (Color?)GetValue(PrimaryColorProperty);
            set => SetValue(PrimaryColorProperty, value);
        }
    }

    public class LongPressButton : Button
    {
        public event EventHandler LongPressed;

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

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