您当前的位置: 首页 > 

君子居易

暂无认证

  • 0浏览

    0关注

    210博文

    0收益

  • 0浏览

    0点赞

    0打赏

    0留言

私信
关注
热门博文

WPF ListBox自动滚动到最新行

君子居易 发布时间:2022-08-18 15:48:22 ,浏览量:0

 自定义附加属性,实现ListBox 自动滚动到最新行,主要通过属性值确认是否订阅ListBox Item变化,根据listBox.Items.CurrentPosition获取当前新增子项所在位置。

public class ListBoxExtenders : DependencyObject
{
    public static readonly DependencyProperty AutoScrollToCurrentItemProperty = DependencyProperty.RegisterAttached("AutoScrollToCurrentItem", typeof(bool), typeof(ListBoxExtenders), new UIPropertyMetadata(default(bool), OnAutoScrollToCurrentItemChanged));

    public static bool GetAutoScrollToCurrentItem(DependencyObject obj)
    {
        return (bool)obj.GetValue(AutoScrollToSelectedItemProperty);
    }

    public static void SetAutoScrollToCurrentItem(DependencyObject obj, bool value)
    {
        obj.SetValue(AutoScrollToSelectedItemProperty, value);
    }

    public static void OnAutoScrollToCurrentItemChanged(DependencyObject s, DependencyPropertyChangedEventArgs e)
    {
        var listBox = s as ListBox;
        if (listBox != null)
        {
            var listBoxItems = listBox.Items;
            if (listBoxItems != null)
            {
                var newValue = (bool)e.NewValue;

                var autoScrollToCurrentItemWorker = new EventHandler((s1, e2) => OnAutoScrollToCurrentItem(listBox, listBox.Items.CurrentPosition));

                if (newValue)
                    listBoxItems.CurrentChanged += autoScrollToCurrentItemWorker;
                else
                    listBoxItems.CurrentChanged -= autoScrollToCurrentItemWorker;
            }
        }
    }

    public static void OnAutoScrollToCurrentItem(ListBox listBox, int index)
    {
        if (listBox != null && listBox.Items != null && listBox.Items.Count > index && index >= 0)
            listBox.ScrollIntoView(listBox.Items[index]);
    }

}

 使用方法:

关注
打赏
1660814979
查看更多评论
立即登录/注册

微信扫码登录

0.0402s