我一直在玩行为,遇到了一个有趣的问题。这是我的行为:
public class AddNewBehavior : BaseBehavior<RadGridView, AddNewBehavior>
{
public static readonly DependencyProperty IsEnabledProperty = DependencyProperty.RegisterAttached("IsEnabled", typeof(bool), typeof(AddNewBehavior), new FrameworkPropertyMetadata(false, OnIsEnabledChanged));
public static void SetIsEnabled(DependencyObject obj, bool isEnabled)
{
obj.SetValue(IsEnabledProperty, isEnabled);
}
public static bool GetIsEnabled(DependencyObject obj)
{
return (bool)obj.GetValue(IsEnabledProperty);
} ... OnIsEnabledChanged(...)}
当我设置这样的样式时,这将非常有用:
<Style TargetType="telerikGridView:RadGridView">
<Setter Property="Behaviors:AddNewBehavior.IsEnabled" Value="true" />
</Style>
但是如果我把它放在一个抽象类中
public abstract class BaseBehavior<TObj, TBehavior> : Behavior<TObj>
where TObj : DependencyObject
where TBehavior : BaseBehavior<TObj, TBehavior>, new()
{
public static readonly DependencyProperty IsEnabledProperty = DependencyProperty.RegisterAttached("IsEnabled", typeof(bool), typeof(TBehavior), new FrameworkPropertyMetadata(false, OnIsEnabledChanged));
public static void SetIsEnabled(DependencyObject obj, bool isEnabled)
{
obj.SetValue(IsEnabledProperty, isEnabled);
}
public static bool GetIsEnabled(DependencyObject obj)
{
return (bool)obj.GetValue(IsEnabledProperty);
}
public static void OnIsEnabledChanged(DependencyObject dpo, DependencyPropertyChangedEventArgs e)
{
BehaviorCollection behaviorCollection = Interaction.GetBehaviors(dpo);
if ((bool)e.NewValue)
{
var firstOrDefault = behaviorCollection.Where(b => b.GetType() == typeof(TBehavior)).FirstOrDefault();
if (firstOrDefault == null)
{
behaviorCollection.Add(new TBehavior());
}
}
}
}
样式声明将与“值不能为空。属性名称:属性”一起粉碎。
想知道我做错了什么,在基类中使用 IsEnabled 代码会很棒。
谢谢,