找不到滚动视图属性以了解滚动视图滚动了多少像素

Posted 2023-03-16

【中文标题】找不到滚动视图属性以了解滚动视图滚动了多少像素

【英文标题】：Cant find the Scroll View property to know how many pixels the scroll view did scroll

【发布时间】：2015-01-02 15:11:21

【问题描述】：

我有一个带有标签的滚动视图，我想在某人向右滚动标签 X px 并松开手指后用动画删除这个标签。

所以我创建了一个委托连接并添加了滚动视图委托方法：

- (void)scrollViewDidScroll:(UIScrollView *)scrollView 

    NSLog(@"scroll view did scroll");

在这个方法中我想说的是：

if myScrollView.someProperty moved X px's to the right and the user pulled his finger 

delete this label sliding with animation to the right

有人可以帮忙吗：/

tnx 领先！！

【问题讨论】：

可能是 scool.contentOffset

【参考方案1】：

检查 UIScrollView 的 contentOffset 属性：

contentOffset - The point at which the origin of the content view is offset 
from the origin of the scroll view.

【参考方案2】：

您可以使用 UISwipeGestureRecognizer 来执行此操作并定义要将标签向右拖动多少像素。你可以试试下面的代码

- (void)viewDidLoad 
    [super viewDidLoad];
    mylabel.userInteractionEnabled=YES;
    [mylabel sizeToFit];
    [mylabel addGestureRecognizer:[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeLabel:)]];



- (void)didSwipeLabel:(UISwipeGestureRecognizer*)swipe

    NSLog(@"swipe");

    swipe.direction = UISwipeGestureRecognizerDirectionRight;
    if (swipe.direction == UISwipeGestureRecognizerDirectionRight) 
        [UIView animateWithDuration:0.5 animations:^
            // swipe the label 50px right
           mylabel.transform = CGAffineTransformMakeTranslation(50.0, 0.0);
         completion:^(BOOL finished) 
            // when animation
            [UIView animateWithDuration:0.5 animations:^
                 NSLog(@"label should be removed");
                [mylabel removeFromSuperview];
            ];
        ];