uiscrollview 的缩放不起作用

问题描述

我不明白为什么滚动视图不起作用，因为我遵循了教程中的建议.

I don't understand why the scrollview isn't working, because I followed advices from tutorials.

我创建了包含 UIImageView 的 UIScrollView 并且还添加了方法

I created the UIScrollView that contains an UIImageView and I also added the method

 - (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
 {
   return imgv;
 }

和界面中的UIScrollViewDelegate，但它不起作用.

and the UIScrollViewDelegate in the interface, but it isn't working.

这是 UIScrollView 的代码:

 imgv = [[UIImageView alloc]
                     initWithFrame:CGRectMake(0, 0, 1000, 500)];
 imgv.image = [UIImage imageWithData:retrievedData];

 scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 800, 800)];
 scrollView setContentSize:CGSizeMake(imgv.image.size.width, imgv.image.size.height)];
 scrollView.maximumZoomScale = 4;
 scrollView.minimumZoomScale = 1;
 [scrollView setScrollEnabled:YES];
 scrollView.clipsToBounds = YES;
 scrollView.delegate = self;

self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(hideImageView)];

 [scrollView addSubview:imgv];
 [view addSubview:scrollView];

如果有人能找出问题所在，我将不胜感激.

I would be thankful, if someone could figure out what the problem could be.

推荐答案

你需要在你的委托方法中返回 imgv viewForZoomingInScrollView::

You need to return imgv in your delegate method viewForZoomingInScrollView::

- (UIView *) viewForZoomingInScrollView:(UIScrollView *) view {
    return imgv;
}