简单的WPF RadioButton绑定？

Question

对于值1,2或3,将一组3个radiobuttons绑定到int类型属性的最简单方法是什么？

Answer 1

我提出了一个简单的解决方案.

我有一个model.cs类:

private int _isSuccess;
public int IsSuccess { get { return _isSuccess; } set { _isSuccess = value; } }

我有Window1.xaml.cs文件,DataContext设置为model.cs.xaml包含radiobuttons:

<RadioButton IsChecked="{Binding Path=IsSuccess, Converter={StaticResource radioBoolToIntConverter}, ConverterParameter=1}" Content="one" />
<RadioButton IsChecked="{Binding Path=IsSuccess, Converter={StaticResource radioBoolToIntConverter}, ConverterParameter=2}" Content="two" />
<RadioButton IsChecked="{Binding Path=IsSuccess, Converter={StaticResource radioBoolToIntConverter}, ConverterParameter=3}" Content="three" />

这是我的转换器:

public class RadioBoolToIntConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        int integer = (int)value;
        if (integer==int.Parse(parameter.ToString()))
            return true;
        else
            return false;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return parameter;
    }
}

当然,在Window1的资源中:

<Window.Resources>
    <local:RadioBoolToIntConverter x:Key="radioBoolToIntConverter" />
</Window.Resources>

Answer 2

实际上,使用像这样的转换器打破了双向绑定,加上我上面所说的,你也不能使用枚举.更好的方法是使用针对ListBox的简单样式,如下所示:

注:相反的是DrWPF.com在他们的例子说明,也没有把里面单选按钮,否则如果添加与内容的项目,如按钮或别的东西,你将无法设定对焦或与其交互的ContentPresenter .这种技术解决了这个问题.此外,您需要处理文本的灰色以及删除标签上的边距,否则它将无法正确呈现.这种风格也适合你.

<Style x:Key="RadioButtonListItem" TargetType="{x:Type ListBoxItem}" >

    <Setter Property="Template">
        <Setter.Value>

            <ControlTemplate TargetType="ListBoxItem">

                <DockPanel LastChildFill="True" Background="{TemplateBinding Background}" HorizontalAlignment="Stretch" VerticalAlignment="Center" >

                    <RadioButton IsChecked="{TemplateBinding IsSelected}" Focusable="False" IsHitTestVisible="False" VerticalAlignment="Center" Margin="0,0,4,0" />

                    <ContentPresenter
                        Content             = "{TemplateBinding ContentControl.Content}"
                        ContentTemplate     = "{TemplateBinding ContentControl.ContentTemplate}"
                        ContentStringFormat = "{TemplateBinding ContentControl.ContentStringFormat}"
                        HorizontalAlignment = "{TemplateBinding Control.HorizontalContentAlignment}"
                        VerticalAlignment   = "{TemplateBinding Control.VerticalContentAlignment}"
                        SnapsToDevicePixels = "{TemplateBinding UIElement.SnapsToDevicePixels}" />

                </DockPanel>

            </ControlTemplate>

        </Setter.Value>

    </Setter>

</Style>

<Style x:Key="RadioButtonList" TargetType="ListBox">

    <Style.Resources>
        <Style TargetType="Label">
            <Setter Property="Padding" Value="0" />
        </Style>
    </Style.Resources>

    <Setter Property="BorderThickness" Value="0" />
    <Setter Property="Background"      Value="Transparent" />

    <Setter Property="ItemContainerStyle" Value="{StaticResource RadioButtonListItem}" />

    <Setter Property="Control.Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ListBox}">
                <ItemsPresenter SnapsToDevicePixels="{TemplateBinding UIElement.SnapsToDevicePixels}" />
            </ControlTemplate>
        </Setter.Value>
    </Setter>

    <Style.Triggers>
        <Trigger Property="IsEnabled" Value="False">
            <Setter Property="TextBlock.Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" />
        </Trigger>
    </Style.Triggers>

</Style>

<Style x:Key="HorizontalRadioButtonList" BasedOn="{StaticResource RadioButtonList}" TargetType="ListBox">
    <Setter Property="ItemsPanel">
        <Setter.Value>
            <ItemsPanelTemplate>
                <VirtualizingStackPanel Background="Transparent" Orientation="Horizontal" />
            </ItemsPanelTemplate>
        </Setter.Value>
    </Setter>
</Style>

您现在拥有单选按钮的外观,但您可以进行双向绑定,并且可以使用枚举.这是如何做...

<ListBox Style="{StaticResource RadioButtonList}"
    SelectedValue="{Binding SomeVal}"
    SelectedValuePath="Tag">

    <ListBoxItem Tag="{x:Static l:MyEnum.SomeOption}"     >Some option</ListBoxItem>
    <ListBoxItem Tag="{x:Static l:MyEnum.SomeOtherOption}">Some other option</ListBoxItem>
    <ListBoxItem Tag="{x:Static l:MyEnum.YetAnother}"     >Yet another option</ListBoxItem>

</ListBox>

此外,由于我们明确地将传承ListBoxItem的样式分离出来而不是将其置于内联中,再次如其他示例所示,您现在可以创建一个新样式来自定义基于每个项目的内容,例如间距.(如果您只是尝试将ListBoxItem作为键控样式来覆盖通用控件目标,则此方法无效.)

这是一个在每个项目上下放置6的边距的示例.(注意你必须通过ItemContainerStyle属性显式应用样式,而不是简单地在ListBox的资源部分中定位ListBoxItem,原因如上所述.)

<Window.Resources>
    <Style x:Key="SpacedRadioButtonListItem" TargetType="ListBoxItem" BasedOn="{StaticResource RadioButtonListItem}">
        <Setter Property="Margin" Value="0,6" />
    </Style>
</Window.Resources>

<ListBox Style="{StaticResource RadioButtonList}"
    ItemContainerStyle="{StaticResource SpacedRadioButtonListItem}"
    SelectedValue="{Binding SomeVal}"
    SelectedValuePath="Tag">

    <ListBoxItem Tag="{x:Static l:MyEnum.SomeOption}"     >Some option</ListBoxItem>
    <ListBoxItem Tag="{x:Static l:MyEnum.SomeOtherOption}">Some other option</ListBoxItem>
    <ListBoxItem Tag="{x:Static l:MyEnum.YetAnother}"     >Ter another option</ListBoxItem>

</ListBox>

Answer 3

我很惊讶没有人想出这种解决方案将它绑定到bool数组.它可能不是最干净的,但它可以很容易地使用:

private bool[] _modeArray = new bool[] { true, false, false};
public bool[] ModeArray
{
    get { return _modeArray ; }
}
public int SelectedMode
{
    get { return Array.IndexOf(_modeArray, true); }
}

在XAML中:

<RadioButton GroupName="Mode" IsChecked="{Binding Path=ModeArray[0], Mode=TwoWay}"/>
<RadioButton GroupName="Mode" IsChecked="{Binding Path=ModeArray[1], Mode=TwoWay}"/>
<RadioButton GroupName="Mode" IsChecked="{Binding Path=ModeArray[2], Mode=TwoWay}"/>

注意:如果您不想默认选中一个,则不需要双向绑定.TwoWay绑定是此解决方案的最大缺点.

优点:

• 不需要代码
• 无需额外课程(IValue转换器)
• 无需额外的枚举
• 不需要bizzare绑定
• 简单易懂
• 没有违反MVVM(嘿,至少我希望如此)

Answer 4

我知道这是过时的方式,但我有一个替代解决方案,它更轻,更简单.从中派生一个类System.Windows.Controls.RadioButton并声明两个依赖属性RadioValue和 RadioBinding.然后在类代码中,覆盖OnChecked并将RadioBinding属性值设置为属性值的RadioValue属性值.在另一个方向上,陷阱RadioBinding使用回调更改为属性,如果新值等于RadioValue属性的值,则将其IsChecked属性设置为true.

这是代码:

public class MyRadioButton : RadioButton
{
    public object RadioValue
    {
        get { return (object)GetValue(RadioValueProperty); }
        set { SetValue(RadioValueProperty, value); }
    }

    // Using a DependencyProperty as the backing store for RadioValue.
       This enables animation, styling, binding, etc...
    public static readonly DependencyProperty RadioValueProperty =
        DependencyProperty.Register(
            "RadioValue", 
            typeof(object), 
            typeof(MyRadioButton), 
            new UIPropertyMetadata(null));

    public object RadioBinding
    {
        get { return (object)GetValue(RadioBindingProperty); }
        set { SetValue(RadioBindingProperty, value); }
    }

    // Using a DependencyProperty as the backing store for RadioBinding.
       This enables animation, styling, binding, etc...
    public static readonly DependencyProperty RadioBindingProperty =
        DependencyProperty.Register(
            "RadioBinding", 
            typeof(object), 
            typeof(MyRadioButton), 
            new FrameworkPropertyMetadata(
                null, 
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, 
                OnRadioBindingChanged));

    private static void OnRadioBindingChanged(
        DependencyObject d,
        DependencyPropertyChangedEventArgs e)
    {
        MyRadioButton rb = (MyRadioButton)d;
        if (rb.RadioValue.Equals(e.NewValue))
            rb.SetCurrentValue(RadioButton.IsCheckedProperty, true);
    }

    protected override void OnChecked(RoutedEventArgs e)
    {
        base.OnChecked(e);
        SetCurrentValue(RadioBindingProperty, RadioValue);
    }
}

XAML用法:

<my:MyRadioButton GroupName="grp1" Content="Value 1"
    RadioValue="val1" RadioBinding="{Binding SelectedValue}"/>
<my:MyRadioButton GroupName="grp1" Content="Value 2"
    RadioValue="val2" RadioBinding="{Binding SelectedValue}"/>
<my:MyRadioButton GroupName="grp1" Content="Value 3"
    RadioValue="val3" RadioBinding="{Binding SelectedValue}"/>
<my:MyRadioButton GroupName="grp1" Content="Value 4"
    RadioValue="val4" RadioBinding="{Binding SelectedValue}"/>

希望有人在这段时间后发现这个有用:)

Answer 5

我想出了使用Binding.DoNothing转换器返回的解决方案，它不会破坏双向绑定。

public class EnumToCheckedConverter : IValueConverter
{
    public Type Type { get; set; }

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value != null && value.GetType() == Type)
        {
            try
            {
                var parameterFlag = Enum.Parse(Type, parameter as string);

                if (Equals(parameterFlag, value))
                {
                    return true;
                }
            }
            catch (ArgumentNullException)
            {
                return false;
            }
            catch (ArgumentException)
            {
                throw new NotSupportedException();
            }

            return false;
        }
        else if (value == null)
        {
            return false;
        }

        throw new NotSupportedException();
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value != null && value is bool check)
        {
            if (check)
            {
                try
                {
                    return Enum.Parse(Type, parameter as string);
                }
                catch(ArgumentNullException)
                {
                    return Binding.DoNothing;
                }
                catch(ArgumentException)
                {
                    return Binding.DoNothing;
                }
            }

            return Binding.DoNothing;
        }

        throw new NotSupportedException();
    }
}

用法：

<converters:EnumToCheckedConverter x:Key="SourceConverter" Type="{x:Type monitor:VariableValueSource}" />

单选按钮绑定：

<RadioButton GroupName="ValueSource" 
             IsChecked="{Binding Source, Converter={StaticResource SourceConverter}, ConverterParameter=Function}">Function</RadioButton>