Wpf 使用拆分器后如何重置网格行高度？

对于以下XAML，取消选中复选框时，最下面一行将隐藏。在使用gridsplitter调整大小之前，一切都很好。然后，选中/取消选中复选框不起任何作用。如果转换器将高度设置为0，我希望该行隐藏。发生什么事？移动拆分器后如何重置高度

<Grid>
    <Grid.Resources>
        <m:CheckedToLengthConverter x:Key="checkedToLengthConverter" />
    </Grid.Resources>
    <Grid.RowDefinitions>
        <RowDefinition Height="3*" />
        <RowDefinition Height="{Binding Mode=OneWay, ElementName=ShowBottomCheckBox, Path=IsChecked, Converter={StaticResource checkedToLengthConverter}, ConverterParameter=2}" />
    </Grid.RowDefinitions>
    <Border Background="Blue" />
    <CheckBox Name="ShowBottomCheckBox" IsChecked="True" />
    <GridSplitter HorizontalAlignment="Stretch" VerticalAlignment="Bottom" Height="5" />
    <Border Background="Red" Grid.Row="1" />
</Grid>

---

问题是，一旦移动拆分器，第一行将具有明确的宽度，因此将最后一行设置回*将不会产生任何效果。经过一些实验，我想出了下面的代码。请注意，您需要指定双向绑定，否则它将无法工作

public class CheckedToLengthConverter : MarkupExtension, IValueConverter
{
    public GridLength TrueValue { get; set; }
    public GridLength FalseValue { get; set; }

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return System.Convert.ToBoolean(value) ? TrueValue : FalseValue;
    }

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

    #region Overrides of MarkupExtension

    public override object ProvideValue(IServiceProvider serviceProvider)
    {
        return this;
    }

    #endregion
}

<Grid>
    <Grid.Resources>
        <m:CheckedToLengthConverter TrueValue="2*" FalseValue="*" x:Key="c1" />
        <m:CheckedToLengthConverter TrueValue="3*" FalseValue="0" x:Key="c2" />
    </Grid.Resources>

    <Grid.RowDefinitions>
        <RowDefinition Height="{Binding Mode=TwoWay, Path=IsChecked, 
                       ElementName=ShowBottomCheckBox, 
                       Converter={StaticResource c1}}"/>
        <RowDefinition Height="auto"/>
        <RowDefinition Height="{Binding Mode=TwoWay, Path=IsChecked, 
                       ElementName=ShowBottomCheckBox, 
                       Converter={StaticResource c2}}"/>
    </Grid.RowDefinitions>
    <Border Background="Blue" />
    <CheckBox Name="ShowBottomCheckBox" IsChecked="True" />
    <GridSplitter HorizontalAlignment="Stretch" 
                  Grid.Row="1" VerticalAlignment="Bottom" Height="5" 
                  ResizeBehavior="PreviousAndNext" />
    <Border Background="Red" Grid.Row="2" />
</Grid>

public类CheckedToLengthConverter:MarkupExtension，IValueConverter
{
公共GridLength TrueValue{get；set；}
公共GridLength错误值{get；set；}
公共对象转换（对象值、类型targetType、对象参数、CultureInfo区域性）
{
返回System.Convert.ToBoolean（值）？TrueValue:FalseValue；
}
公共对象转换回（对象值、类型targetType、对象参数、CultureInfo区域性）
{
不做任何事；
}
#MarkupExtension的区域覆盖
公共覆盖对象ProviderValue（IServiceProvider服务提供程序）
{
归还这个；
}
#端区
}

这是用户体验问题，而不是代码。你想做的没有什么意义，你试过用视觉状态来代替吗

public class CheckedToLengthConverter : MarkupExtension, IValueConverter
{
    public GridLength TrueValue { get; set; }
    public GridLength FalseValue { get; set; }

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return System.Convert.ToBoolean(value) ? TrueValue : FalseValue;
    }

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

    #region Overrides of MarkupExtension

    public override object ProvideValue(IServiceProvider serviceProvider)
    {
        return this;
    }

    #endregion
}

<Grid>
    <Grid.Resources>
        <m:CheckedToLengthConverter TrueValue="2*" FalseValue="*" x:Key="c1" />
        <m:CheckedToLengthConverter TrueValue="3*" FalseValue="0" x:Key="c2" />
    </Grid.Resources>

    <Grid.RowDefinitions>
        <RowDefinition Height="{Binding Mode=TwoWay, Path=IsChecked, 
                       ElementName=ShowBottomCheckBox, 
                       Converter={StaticResource c1}}"/>
        <RowDefinition Height="auto"/>
        <RowDefinition Height="{Binding Mode=TwoWay, Path=IsChecked, 
                       ElementName=ShowBottomCheckBox, 
                       Converter={StaticResource c2}}"/>
    </Grid.RowDefinitions>
    <Border Background="Blue" />
    <CheckBox Name="ShowBottomCheckBox" IsChecked="True" />
    <GridSplitter HorizontalAlignment="Stretch" 
                  Grid.Row="1" VerticalAlignment="Bottom" Height="5" 
                  ResizeBehavior="PreviousAndNext" />
    <Border Background="Red" Grid.Row="2" />
</Grid>