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为什么我不能在Silverlight4中绑定DataGridTemplateColumn的可见性?

silverlight-4.0 data-binding silverlight

Rodney · 技术社区 · 14 年前

似乎无法在Silverlight4中绑定DataGridTemplateColumn的可见性属性。我在谷歌上搜索了一下,好像有几个帖子暗示我要这么做。 with the fact that it was not a DependencyObject 以及如何 this would change in SL4 但情况似乎并非如此。

为了解决这个问题,我在DataGrid加载事件后面的代码中做了这个工作,但是我很好奇为什么会这样?

以下是我得到的错误消息(使用返回可见性值的转换器):

{System.ArgumentException: Object of type 'System.Windows.Data.Binding' cannot be converted to type 'System.Windows.Visibility'.
   at System.RuntimeType.TryChangeType(Object value, Binder binder, CultureInfo culture, Boolean needsSpecialCast)
   at System.RuntimeType.CheckValue(Object value, Binder binder, CultureInfo culture, BindingFlags invokeAttr)
   at System.Reflection.MethodBase.CheckArguments(Object[] parameters, Binder binder, BindingFlags invokeAttr, CultureInfo culture, Signature sig)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.Reflection.RuntimePropertyInfo.SetValue(Object obj, Object value, BindingFlags invokeAttr, Binder binder, Object[] index, CultureInfo culture)
   at System.Reflection.RuntimePropertyInfo.SetValue(Object obj, Object value, Object[] index)
   at MS.Internal.XamlMemberInfo.SetValue(Object target, Object value)
   at MS.Internal.XamlManagedRuntimeRPInvokes.SetValue(XamlTypeToken inType, XamlQualifiedObject& inObj, XamlPropertyToken inProperty, XamlQualifiedObject& inValue)}

2 回复 | 直到 12 年前

AnthonyWJones 14 年前

同时 DataGridTemplateColumn 是否源自 DependencyObject 它没有定义 DependencyProperty 因为它的可见性属性。实际上,它没有定义任何依赖属性,因此您仍然无法在其上绑定任何内容。

Stuart Bale 12 年前

对于要绑定到的任何属性,请在“数据网格模板”列上使用此选项:

public class CustomDataGridTemplateColumn : DataGridTemplateColumn
{
    public static readonly DependencyProperty VisibilityBindingProperty = DependencyProperty.Register(
      "VisibilityBinding", typeof(Visibility), typeof(CustomDataGridTemplateColumn), new PropertyMetadata(Visibility.Collapsed, new PropertyChangedCallback(OnVisibilityChanged)));

    public Visibility VisibilityBinding
    {
        get { return (Visibility)this.GetValue(VisibilityBindingProperty); }
        set { this.SetValue(VisibilityBindingProperty, value); }
    }

    private static void OnVisibilityChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        ((CustomDataGridTemplateColumn)d).Visibility = (Visibility)e.NewValue;
    }
}