在iPhone中使用UIPichGestureRecognizer执行picture后图像大小重置为原始大小

Question

我有一个视图控制器，其中添加了 UIScrollView 和 UIScrollView 。 UIImageView 以编程方式。我已将 UIPichGestureRecognizer 添加到 UIImageView 中。我的 UIImageView 作为子视图添加到 UIScrollView 中。

我的问题是，当我尝试捏合图像时，它会放大。但是当我从屏幕上释放触摸时，它会再次恢复到默认大小。我找不到代码中的错误。请帮我。 下面是我的代码

 - (void)createUserInterface {

    scrollViewForImage = [[UIScrollView alloc]initWithFrame:CGRectMake(20.0f, 60.0f, 280.0f, 200.0f)];
    scrollViewForImage.userInteractionEnabled = YES;
    scrollViewForImage.multipleTouchEnabled = YES;
    scrollViewForImage.backgroundColor = [UIColor redColor];
    scrollViewForImage.autoresizesSubviews = YES;
    scrollViewForImage.maximumZoomScale = 1;
    scrollViewForImage.minimumZoomScale = .50;
    scrollViewForImage.clipsToBounds = YES;
    scrollViewForImage.delegate = self;
    scrollViewForImage.bouncesZoom = YES;
    scrollViewForImage.contentMode = UIViewContentModeScaleToFill;
    [self.contentView addSubview:scrollViewForImage];

    imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0.0f, 0.0f, 280.0f, 200.0f)];
    [imageView setBackgroundColor:[UIColor clearColor]];
    imageView.userInteractionEnabled = YES;
    imageView.multipleTouchEnabled = YES;

    UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinch:)];
        [pinchRecognizer setDelegate:self];
        [imageView addGestureRecognizer:pinchRecognizer];
    //[self.contentView addSubview:imageView];
    [self.scrollViewForImage addSubview:imageView];

    scrollViewForImage.contentSize = CGSizeMake(imageView.frame.size.width , imageView.frame.size.height);

}


-(UIView *) viewForZoomingInScrollView:(UIScrollView *)inScroll {
    return imageView;
}

-(void)pinch:(id)sender {

    [self.view bringSubviewToFront:[(UIPinchGestureRecognizer*)sender view]];

    if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {

        lastScale = 1.0;
        return;
    }

    CGFloat scale = 1.0 - (lastScale - [(UIPinchGestureRecognizer*)sender scale]);
    CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform;
    CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);
    [[(UIPinchGestureRecognizer*)sender view] setTransform:newTransform];
    lastScale = [(UIPinchGestureRecognizer*)sender scale];
}

Answer 1

据我所知，问题出在这里：

scrollViewForImage.maximumZoomScale = 1;

您将图像的最大缩放比例设置为其完整尺寸的 1 倍。这意味着一旦您完成捏合图像，它将缩小到其大小的 1 倍。

如果您希望能够将图像缩放到更大的尺寸，请尝试将此值设置为高于 1。例如

scrollViewForImage.maximumZoomScale = 3;