WPF ListBox OnScroll事件

Question

我想弄清楚如何做(应该)相当简单的事情.

我想要的是在滚动ListBox控件的任何时候触发事件.ListBox是动态创建的,所以我需要一种方法从后面的代码中完成它(但是XAML解决方案也很受欢迎,因为它给了我一些开始).

提前感谢任何想法.

Answer 1

在XAML中,您可以访问ScrollViewer并添加如下事件:

<ListBox Name="listBox" ScrollViewer.ScrollChanged="listBox_ScrollChanged"/>

更新
这可能是你需要的代码背后:

List<ScrollBar> scrollBarList = GetVisualChildCollection<ScrollBar>(listBox);
foreach (ScrollBar scrollBar in scrollBarList)
{
    if (scrollBar.Orientation == Orientation.Horizontal)
    {
        scrollBar.ValueChanged += new RoutedPropertyChangedEventHandler<double>(listBox_HorizontalScrollBar_ValueChanged);
    }
    else
    {
        scrollBar.ValueChanged += new RoutedPropertyChangedEventHandler<double>(listBox_VerticalScrollBar_ValueChanged);
    }
}

使用GetVisualChildCollection的实现:

public static List<T> GetVisualChildCollection<T>(object parent) where T : Visual
{
    List<T> visualCollection = new List<T>();
    GetVisualChildCollection(parent as DependencyObject, visualCollection);
    return visualCollection;
}
private static void GetVisualChildCollection<T>(DependencyObject parent, List<T> visualCollection) where T : Visual
{
    int count = VisualTreeHelper.GetChildrenCount(parent);
    for (int i = 0; i < count; i++)
    {
        DependencyObject child = VisualTreeHelper.GetChild(parent, i);
        if (child is T)
        {
            visualCollection.Add(child as T);
        }
        else if (child != null)
        {
            GetVisualChildCollection(child, visualCollection);
        }
    }
}