下拉加载

/// <summary>
/// 查找控件
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="root"></param>
/// <returns></returns>
public static T FindChildOfType<T>(Windows.UI.Xaml.DependencyObject root) where T : class
{
var queue = new Queue<Windows.UI.Xaml.DependencyObject>();
queue.Enqueue(root);
while (queue.Count > 0)
{
var current = queue.Dequeue();
for (int i = 0; i < Windows.UI.Xaml.Media.VisualTreeHelper.GetChildrenCount(current); i++)
{
var child = Windows.UI.Xaml.Media.VisualTreeHelper.GetChild(current, i);
var result = child as T;
if (result != null)
{
return result;
}
queue.Enqueue(child);
}

}
return null;
}

在页面加载的时候

 this.gvData.Loaded += (s1, e2) =>
            {
                if (listData == null)
                    listData = new System.Collections.ObjectModel.ObservableCollection<DataModel.DiabetesKnowledgeModel>();
                scrollView = MiscHelper.FindChildOfType<ScrollViewer>(gvData);
                if (scrollView != null)
                {
                    scrollView.ViewChanged += ScrollView_ViewChanged;
                }
                this.gvData.ItemsSource = listData;
                page = 1;
//加载内容
                GetList();
            };

   isLoading = true;
//这里加载内容

   private bool isLoading = false;  
 private bool isRefresh = true;
private ScrollViewer scrollView;
   private void ScrollView_ViewChanged(object sender, ScrollViewerViewChangedEventArgs e)
        {
            if (isLoading)
                return;
            if (scrollView.ScrollableHeight > scrollView.ScrollableWidth)
            {
                if (scrollView.VerticalOffset >= scrollView.ScrollableHeight)
                {
                    page++;
                    isRefresh = false;
                    GetKnowledgeList();
                }
            }
            else
            {
                if (scrollView.HorizontalOffset >= scrollView.ScrollableWidth)
                {
                    page++;
                    isRefresh = false;
                    GetKnowledgeList();
                }
            }

        }