UIScrollview有多个图像和捏缩放

Question

我想在iPhone上复制照片应用程序.意思是,具有多个图像的滚动视图,以及每个图像可以被挤压以放大/缩小.

Apple ScrollViewSuite示例代码仅处理scrollview内的1个图像.我发现,对于多个图像,滚动图像变得不可预测.此外,在缩放缩放后视图也会被取消.

我在Stack Overflow上找到了这个:用多个图像缩放UIScrollView

但是,我应该在scrollview委托函数中写什么？

Answer 1

这是我发现的工作.通过分页和缩放支持多个图像.请享用!

#define VIEW_FOR_ZOOM_TAG (1)

@implementation SVViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    UIScrollView *mainScrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
    mainScrollView.pagingEnabled = YES;
    mainScrollView.showsHorizontalScrollIndicator = NO;
    mainScrollView.showsVerticalScrollIndicator = NO;

    CGRect innerScrollFrame = mainScrollView.bounds;

    for (NSInteger i = 0; i < 3; i++) {
        UIImageView *imageForZooming = [[UIImageView alloc] initWithImage:[UIImage imageNamed:  
        [NSString stringWithFormat:@"page%d", i + 1]]];
        imageForZooming.tag = VIEW_FOR_ZOOM_TAG;

        UIScrollView *pageScrollView = [[UIScrollView alloc] initWithFrame:innerScrollFrame];
        pageScrollView.minimumZoomScale = 1.0f;
        pageScrollView.maximumZoomScale = 2.0f;
        pageScrollView.zoomScale = 1.0f;
        pageScrollView.contentSize = imageForZooming.bounds.size;
        pageScrollView.delegate = self;
        pageScrollView.showsHorizontalScrollIndicator = NO;
        pageScrollView.showsVerticalScrollIndicator = NO;
        [pageScrollView addSubview:imageForZooming];

        [mainScrollView addSubview:pageScrollView];

        if (i < 2) {
            innerScrollFrame.origin.x += innerScrollFrame.size.width;
        }
    }

    mainScrollView.contentSize = CGSizeMake(innerScrollFrame.origin.x + 
    innerScrollFrame.size.width, mainScrollView.bounds.size.height);

    [self.view addSubview:mainScrollView];
}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
    return [scrollView viewWithTag:VIEW_FOR_ZOOM_TAG];
}

- (NSUInteger)supportedInterfaceOrientations {
    return UIInterfaceOrientationMaskPortrait;
} 

- (BOOL)shouldAutorotate {
    return NO;
}

@end