0

必须有比以下更好的方法来获取“childItem”

    TaskItem task = (sender as Canvas).DataContext as TaskItem;
    TaskItem child = Tasks.CreateTask("New task", task);
    TreeViewItem item = treeView.ItemContainerGenerator.ContainerFromItem(task) as TreeViewItem;            

    item.UpdateLayout();
    TreeViewItem childItem = null;
    foreach (var i in item.GetDescendantContainers())
    {
        if (i.GetItem() == child)
            childItem = i;
    }

由于某种原因 item.ItemGenerator.ContainerFromItem(child) 不起作用(必须是由于刚刚创建的项目)

4

1 回答 1

0

项目容器的生成是异步的,因此您不能假设一旦添加项目,容器就会存在。您需要将处理程序附加到ItemContainerGenerator.StatusChanged事件,以便在容器生成完成时通知您的代码。

WPF 博士的博文“ItemsControl: 'G' is for Generator”很好地描述了该问题,并提供了使用 StatusChanged 的​​示例:

private void AddScooby()
{
    _scooby = new Character("Scooby Doo");
    Characters.Add(_scooby);
    CharacterListBox.ItemContainerGenerator.StatusChanged
        += OnStatusChanged;
}

private void OnStatusChanged(object sender, EventArgs e)
{
    if (CharacterListBox.ItemContainerGenerator.Status
        == GeneratorStatus.ContainersGenerated)
    {
        CharacterListBox.ItemContainerGenerator.StatusChanged
            -= OnStatusChanged;
        ListBoxItem lbi = CharacterListBox.ItemContainerGenerator
            .ContainerFromItem(_scooby) as ListBoxItem;
        if (lbi != null)
        {
            lbi.IsSelected = true;
        }
    }
}
于 2010-07-24T13:16:51.383 回答