osu-lazer/osu.Game/Overlays/Settings/SettingsDropdown.cs

// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE

using System.Collections.Generic;
using System.Linq;
using osu.Framework.Graphics;
using osu.Game.Graphics.UserInterface;

namespace osu.Game.Overlays.Settings
{
    public class SettingsDropdown<T> : SettingsItem<T>
    {
        protected new OsuDropdown<T> Control => (OsuDropdown<T>)base.Control;

        private IEnumerable<T> items = Enumerable.Empty<T>();

        public IEnumerable<T> Items
        {
            get => items;
            set
            {
                items = value;

                if (Control != null)
                    Control.Items = value;
            }
        }

        protected sealed override Drawable CreateControl() => CreateDropdown();

        protected virtual OsuDropdown<T> CreateDropdown() => new DropdownControl { Items = Items };

        protected class DropdownControl : OsuDropdown<T>
        {
            public DropdownControl()
            {
                Margin = new MarginPadding { Top = 5 };
                RelativeSizeAxes = Axes.X;
            }
        }
    }
}