uiscrollview的缩放功能无效 [英] The zoom for uiscrollview isn't working

问题描述

我不明白为什么scrollview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 UIScrollView 包含 UIImageView ，我还添加了方法

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

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

和 UIScrollViewDelegate 在界面中，但它不起作用。

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

以下是 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];

如果有人能弄明白问题是什么，我会很感激。

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

推荐答案

您需要在委托方法中返回 imgv viewForZoomingInScrollView：：

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

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

这篇关于uiscrollview的缩放功能无效的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！