aurora/Aurora/Design/Components/ImageButton/ImageButton.xaml.cs

using System;
using System.Collections.Generic;
using Xamarin.Forms;

namespace Aurora.Design.Components.ImageButton
{
    public partial class ImageButton : ContentView
    {
        public ImageButton()
        {
            InitializeComponent();
        }

        public static readonly BindableProperty SourceProperty =
            BindableProperty.Create(
                "Source",
                typeof(ImageSource),
                typeof(ImageButton),
                null,
                BindingMode.TwoWay,
                propertyChanged: (bindable, oldValue, newValue) =>
                {
                    ImageButton control = (ImageButton)bindable;

                    control.imgButton.Source = (ImageSource)newValue;
                });

        public static readonly BindableProperty CommandProperty = BindableProperty.Create(
            "Command",
            typeof(Command),
            typeof(ImageButton),
            null,
            propertyChanged: (bindable, oldValue, newValue) =>
            {
                ImageButton control = (ImageButton)bindable;
                var command = (Command)newValue;

                CanExecute(command, control);

                command.CanExecuteChanged += (sender, e) =>
                {
                    CanExecute(sender, control);
                };
            });

        public static readonly BindableProperty CommandParameterProperty = BindableProperty.Create(
            "CommandParameter",
            typeof(object),
            typeof(ImageButton),
            null);

        private static void CanExecute(object sender, ImageButton control)
        {
            var cmd = (Command)sender;
            control.imgButton.IsEnabled = cmd.CanExecute(null);
        }

        public ImageSource Source
        {
            get { return (ImageSource)GetValue(SourceProperty); }
            set { SetValue(SourceProperty, value); }
        }


        public event EventHandler<EventArgs> Tapped;

        public Command Command
        {
            get { return (Command)GetValue(CommandProperty); }
            set { SetValue(CommandProperty, value); }
        }

        public object CommandParameter
        {
            get { return GetValue(CommandParameterProperty); }
            set { SetValue(CommandParameterProperty, value); }
        }

        protected void OnButtonTapped(object sender, EventArgs args)
        {
            object resolvedParameter;

            if (CommandParameter != null)
            {
                resolvedParameter = CommandParameter;
            }
            else
            {
                resolvedParameter = args;
            }

            if (Command?.CanExecute(resolvedParameter) ?? true)
            {
                this.AbortAnimation("imgButtonAnim");
                new Animation(v => imgButton.Scale = v, 1, 0.5).Commit(imgButton, "imgButtonAnim", 16, 150, Easing.SinOut,
                    (v, c) =>
                    {
                        imgButton.Scale = 1;
                        Tapped?.Invoke(this, args);
                        Command?.Execute(resolvedParameter);
                    });
            }
        }
    }
}