今天遇到一个问题,需要把 打开的页面中 ,显示 其中 ListBox 的最后一项,试探着写了下面的代码,结果成功了,但是回头还需要研究一下,先记下来:
static T FindChildOfType<T>(DependencyObject root) where T : class
{
var queue = new Queue<DependencyObject>();
queue.Enqueue(root);
while (queue.Count > 0)
{
DependencyObject current = queue.Dequeue();
for (int i = VisualTreeHelper.GetChildrenCount(current) - 1; 0 <= i; i--)
{
var child = VisualTreeHelper.GetChild(current, i);
var typedChild = child as T;
if (typedChild != null)
{
return typedChild;
}
queue.Enqueue(child);
}
}
return null;
}
调用时:
ScrollViewer scrollViewer = FindChildOfType<ScrollViewer>(messagesListBox);
if (scrollViewer != null)
{
scrollViewer.ScrollToVerticalOffset(100);
}