Question

我有一个已知的错误

System.Windows.Data错误：2：无法为目标元素找到管理FrameworkElement或FrameworkContentElement.BindingExpression：Path = Percent;的DataItem = NULL; target元素是'GradientStop'（HashCode = 81530）; target属性为'Offset'（类型为'Double'）

这部分代码：

        <DataGrid.RowStyle>
            <Style TargetType="DataGridRow">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding State}" Value="Started">
                        <Setter Property="Background">
                            <Setter.Value>
                                <LinearGradientBrush EndPoint="1,0" StartPoint="0,0">
                                    <GradientStop Color="Green" Offset="0" />
                                    <GradientStop Color="#FF2D2D30" Offset="{Binding Percent}" />
                                </LinearGradientBrush>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                    <Trigger Property="Validation.HasError" Value="true">
                        <Setter Property="BorderThickness" Value="1"/>
                        <Setter Property="BorderBrush" Value="Red"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
        </DataGrid.RowStyle>

我尝试将DataContext设置为代理，但它不起作用：

        <DataGrid.Resources>
            <app:BindingProxy x:Key="proxy" Data="{Binding}" />
        </DataGrid.Resources>

        [...]
        <GradientStop Color="#FF2D2D30" Offset="{Binding Data.Percent, Source={StaticResource proxyRow}}" />

System.Windows.Data错误：40：BindingExpression路径错误：'object'''ViewModel'（HashCode = 37637549）'上找不到'Percent'属性。 BindingExpression：路径= Data.Percent; DataItem ='BindingProxy'（HashCode = 3342738）; target元素是'GradientStop'（HashCode = 64874797）; target属性为'Offset'（类型为'Double'）

这很明显，因为Data现在包含Control的DataContext，它是我的ViewModel。

有什么建议吗？谢谢！

Answer 1

正如其他帖子所说，我认为这不适用于我的问题，但使用转换器非常适合！以下是一些参考文献：

Binding GradientStop works but reports error

How to bind GradientStop Colours or GradientStops Property in Silverlight?

    public object Convert(object value, Type targetType, object parameter,
        System.Globalization.CultureInfo culture)
    {
        Model.ListParameters parameters = (Model.ListParameters)value;
        if(parameters !=null)
        {
            var start = new GradientStop();
            start.Color = Colors.Green;
            start.Offset = 0;

            var stop = new GradientStop();
            stop.Color = (Color)ColorConverter.ConvertFromString("#FF2D2D30");
            stop.Offset = parameters .Percent;

            var result = new LinearGradientBrush();
            result.StartPoint = new Point(0, 0);
            result.EndPoint = new Point(1, 0);
            result.GradientStops.Add(start);
            result.GradientStops.Add(stop);

            return result;
        }
        return null;
    }

和XAML

<UserControl.Resources>
   <app:GradientProgressConverter  x:Key="GradientProgressConverter" />
</UserControl.Resources>
<DataGrid>
   <DataGrid.RowStyle>
      <Style TargetType="DataGridRow">
         <Style.Triggers>
            <DataTrigger Binding="{Binding State}" Value="Started">
                <Setter Property="Background" Value="{Binding Converter={StaticResource GradientProgressConverter}}" />
            </DataTrigger>
         </Style.Triggers>
      </Style>
   </DataGrid.RowStyle>
</<DataGrid>

WPF datagrid.rowstyle绑定

1 个答案: