MvxColorValueConverter.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MS-PL license.
// See the LICENSE file in the project root for more information.
#nullable enable
using System.Globalization;
using MvvmCross.Converters;
using MvvmCross.UI;

namespace MvvmCross.Plugin.Color;

public abstract class MvxColorValueConverter : MvxValueConverter
{
    private readonly Lazy<IMvxNativeColor?> _nativeColor = new(() => Mvx.IoCProvider?.Resolve<IMvxNativeColor>());

    protected abstract System.Drawing.Color Convert(object value, object? parameter, CultureInfo? culture);

    public sealed override object Convert(object value, Type? targetType, object? parameter,
        CultureInfo? culture)
    {
        return _nativeColor.Value?.ToNative(Convert(value, parameter, culture)) ?? MvxBindingConstant.UnsetValue;
    }
}

public abstract class MvxColorValueConverter<T> : MvxColorValueConverter
{
    protected sealed override System.Drawing.Color Convert(object value, object? parameter, CultureInfo? culture)
    {
        if (value is T t)
            return Convert(t, parameter, culture);

        return default;
    }

    protected abstract System.Drawing.Color Convert(T value, object? parameter, CultureInfo? culture);
}