禁用屏幕顶部的UIScrollView反弹

Question

我的应用程序中启用了垂直反弹的UIScrollView。我需要屏幕底部的反弹，但屏幕顶部没有启用。

我就没怎么检测滚动型有以下：

(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView { 

    // no bounce if scrollView has reached the top of the screen ?? 
    } 

Answer 1

尝试将bounces属性作为滚动视图滚动的基础上，内容偏移：

- (void)scrollViewDidScroll:(UIScrollView *)scrollView 
{ 
    scrollView.bounces = (scrollView.contentOffset.y > 100); 
} 

Answer 2

SWIFT

func scrollViewDidScroll(_ scrollView: UIScrollView) { 
    //disable bounce only at the top of the screen 
    scrollView.bounces = scrollView.contentOffset.y > 100 
}