在 WinUI3 中将枚举绑定到 RadioButton TwoWay

Question

我想将

enum

绑定到

WinUI3

中的一些单选按钮，我尝试了

Wpf

中使用的几种解决方案，但它们都无法在

WinUI3

中运行

这是我最后的尝试：

    // My actual enum
    public enum PPGSensorType
    {
        Reflective = 1,
        Transmission = 2
    }

    public class EnumToBooleanConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, string language)
        {
            string parameterString = parameter as string;

            if (parameterString == null)
                return false;

            if (Enum.IsDefined(value.GetType(), value) == false)
                return false;

            object parameterValue = Enum.Parse(value.GetType(), parameterString);

            return parameterValue.Equals(value);
        }

        // TargetType is `Object` in ConvertBack. I don't know what to do about it.
        public object ConvertBack(object value, Type targetType, object parameter, string language)
        {
            string parameterString = parameter as string;

            if (parameterString == null)
                throw new ArgumentException("Parameter should be passed for parsing the enum value.");

            return Enum.Parse(targetType, parameterString);
        }
    }

正如我在上面提到的，

TargetType

是转换回来的

Object

，所以它无法正确转换回值。

<RadioButtons>
    <RadioButton Margin="20 0 0 0" IsChecked="{Binding ElementName=addDeviceDialog, Path=ViewModel.Device.PPGSensorType, Converter={StaticResource EnumToBooleanConverter}, ConverterParameter=Reflective,Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Content="Reflective"/>
    <RadioButton Margin="20 0 0 0" IsChecked="{Binding ElementName=addDeviceDialog, Path=ViewModel.Device.PPGSensorType, Converter={StaticResource EnumToBooleanConverter}, ConverterParameter=Transmission, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Content="Transmission"/>
</RadioButtons>

我尝试了一种使用静态资源来告知 Converter 参数的确切值的新方法。在

app.xaml

中，我添加了以下资源：

<presentation:PPGSensorType x:Key="ReflectivePPGSensor">Reflective</presentation:PPGSensorType>
<presentation:PPGSensorType x:Key="TransmissionPPGSensor">Transmission</presentation:PPGSensorType>

<RadioButtons>
    <RadioButton Margin="20 0 0 0" IsChecked="{Binding ElementName=addDeviceDialog, Path=ViewModel.Device.PPGSensorType, Converter={StaticResource EnumToBooleanConverter}, ConverterParameter={StaticResource ReflectivePPGSensor},Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Content="Reflective"/>
    <RadioButton Margin="20 0 0 0" IsChecked="{Binding ElementName=addDeviceDialog, Path=ViewModel.Device.PPGSensorType, Converter={StaticResource EnumToBooleanConverter}, ConverterParameter={StaticResource TransmissionPPGSensor}, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Content="Transmission"/>
</RadioButtons>

它也不起作用。

Answer 1

这应该有效：

MainPageViewModel.cs

public partial class MainPageViewModel : ObservableObject
{
    [ObservableProperty]
    private List<Color> _colors = Enum.GetValues<Color>().ToList();

    [ObservableProperty]
    private Color? _selectedColor = Color.Red;

    partial void OnSelectedColorChanged(Color? oldValue, Color? newValue)
    {
        System.Diagnostics.Debug.WriteLine($"SelectedColor changed from {oldValue} to {newValue}");
    }
}

主页.xaml

<RadioButtons
    ItemsSource="{x:Bind ViewModel.Colors, Mode=OneWay}"
    SelectedItem="{x:Bind ViewModel.SelectedColor, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />