如何找到ComboBoxItem的ParentComboBox?

时间:2010-03-08 08:05:36

标签: wpf combobox

如何获取ComboBoxItem的ParentComboBox?

如果按下 Insert -Key,我想关闭一个打开的ComboBox:

 var focusedElement = Keyboard.FocusedElement;
 if (focusedElement is ComboBox)
 {
     var comboBox = focusedElement as ComboBox;
     comboBox.IsDropDownOpen = !comboBox.IsDropDownOpen;
 }
 else if (focusedElement is ComboBoxItem)
 {
     var comboBoxItem = focusedElement as ComboBoxItem;
     var parent = comboBoxItem.Parent; //this is null
     var parent = comboBoxItem.ParentComboBox; //ParentComboBox is private
     parent.IsDropDownOpen = !parent.IsDropDownOpen;
 }

看起来这个问题没有直接的解决方案..

2 个答案:

答案 0 :(得分:4)

基本上,您想要检索特定类型的祖先。为此,我经常使用以下方法:

public static class DependencyObjectExtensions
{

    public static T FindAncestor<T>(this DependencyObject obj) where T : DependencyObject
    {
        return obj.FindAncestor(typeof(T)) as T;
    }

    public static DependencyObject FindAncestor(this DependencyObject obj, Type ancestorType)
    {
        var tmp = VisualTreeHelper.GetParent(obj);
        while (tmp != null && !ancestorType.IsAssignableFrom(tmp.GetType()))
        {
            tmp = VisualTreeHelper.GetParent(tmp);
        }
        return tmp;
    }

}

您可以按如下方式使用它:

var parent = comboBoxItem.FindAncestor<ComboBox>();

答案 1 :(得分:0)

与H.B. wrote也可以使用

var parent = ItemsControl.ItemsControlFromItemContainer(comboBoxItem) as ComboBox;