关于TreeView ItemContainerGenerator.ContainerFromIndex 的到的值为null的处理

来源：互联网发布：美国天然气库存数据编辑：程序博客网时间：2024/06/15 22:11

在TreeView中遍历子节点的时候，未展开的节点通过ItemContainerGenerator.ContainerFromIndex是得不到的，所以在遍历额时候应该对未展开的节点的，IsExpanded属性为true，并且要（需要展开的节点）.UpdateLayout();更新树形结构，如下图贴张遍历树的代码：

public PublicControl.MultiSelectTreeViewItem FindTreeViewItem(ItemsControl container, object item)
        {
            if (null == container || null == item)
            {
                return null;
            }

            if (container.DataContext == item)
            {
                return container as PublicControl.MultiSelectTreeViewItem;
            }
            if ((container is PublicControl.MultiSelectTreeViewItem) && !((PublicControl.MultiSelectTreeViewItem)container).IsExpanded)
            {
                container.SetValue(PublicControl.MultiSelectTreeViewItem.IsExpandedProperty, true);
                container.UpdateLayout();
            }
            int count = container.Items.Count;
            for (int i = 0; i < count; i++)
            {
                DependencyObject dp = container.ItemContainerGenerator.ContainerFromIndex(i);
                PublicControl.MultiSelectTreeViewItem subContainer = (PublicControl.MultiSelectTreeViewItem)container.ItemContainerGenerator.ContainerFromIndex(i);
                //PublicControl.MultiSelectTreeViewItem subContainer = container.ItemContainerGenerator.ContainerFromItem(Items[i]) as PublicControl.MultiSelectTreeViewItem;
                if (null == subContainer)
                {
                    continue;
                }
                // Search the next level for the object.
                PublicControl.MultiSelectTreeViewItem resultContainer = FindTreeViewItem(subContainer, item);

                if (null != resultContainer)
                {
                    return resultContainer;
                }
            }
            return null;
        }

PublicControl.MultiSelectTreeViewItem类是我扩展的TreeViewItem，可以根据情况改成自己扩展的类。

参考：http://www.cnblogs.com/muzizongheng/p/3166601.html

http://msdn.microsoft.com/zh-cn/library/vstudio/ff407130.aspx

0 0