我想放大/缩小包含UIScrollView的{{1}}。使用下面的代码我只能滚动滚动视图内容但不能缩放它。
我的视图层次结构如下所示：
UIImageView代码：
- (UIView *) containerView
-- (UIView *) contentView
--- (UIScrollView *) scrollView
---- (UIImageView *) self.imageView
我相信scrollView正在获取它的UIView *previousContentView = nil;
for (NSInteger i = 0; i < 2; i++) {
contentView = [self addRandomColoredView];
[containerView addSubview:contentView];
[containerView.topAnchor constraintEqualToAnchor:contentView.topAnchor].active = true;
[containerView.bottomAnchor constraintEqualToAnchor:contentView.bottomAnchor].active = true;
scrollView = [self addRandomScrollView];
[contentView addSubview:scrollView];
self.imageView = [[UIImageView alloc] init];
[self.imageView setImage:[imagesArray objectAtIndex:i]];
[self.imageView setTranslatesAutoresizingMaskIntoConstraints:false];
[scrollView addSubview:self.imageView];
if (previousContentView) {
[VerticalSeparatorView addSeparatorBetweenView:previousContentView secondView:contentView];
NSLayoutConstraint *width = [contentView.widthAnchor constraintEqualToAnchor:previousContentView.widthAnchor];
width.priority = 250;
width.active = true;
} else {
[containerView.leadingAnchor constraintEqualToAnchor:contentView.leadingAnchor].active = true;
}
[contentView.topAnchor constraintEqualToAnchor:scrollView.topAnchor].active = true;
[contentView.bottomAnchor constraintEqualToAnchor:scrollView.bottomAnchor].active = true;
[contentView.leadingAnchor constraintEqualToAnchor:scrollView.leadingAnchor].active = true;
[contentView.trailingAnchor constraintEqualToAnchor:scrollView.trailingAnchor].active = true;
[scrollView.topAnchor constraintEqualToAnchor:self.imageView.topAnchor].active = true;
[scrollView.bottomAnchor constraintEqualToAnchor:self.imageView.bottomAnchor].active = true;
[scrollView.leadingAnchor constraintEqualToAnchor:self.imageView.leadingAnchor].active = true;
[scrollView.trailingAnchor constraintEqualToAnchor:self.imageView.trailingAnchor].active = true;
previousContentView = contentView;
}
[containerView.trailingAnchor constraintEqualToAnchor:previousContentView.trailingAnchor].active = true;
- (UIView *)addRandomColoredView
{
UIView *someView = [[UIView alloc] init];
someView.translatesAutoresizingMaskIntoConstraints = false;
[someView setBackgroundColor:[UIColor blackColor]];
return someView;
}
-(UIScrollView *)addRandomScrollView
{
UIScrollView *scrollView = [[UIScrollView alloc] init];
[scrollView setDelegate:self];
[scrollView setTranslatesAutoresizingMaskIntoConstraints:false];
[scrollView setBackgroundColor:[UIColor colorWithRed:arc4random_uniform(256)/255.0 green:arc4random_uniform(256)/255.0 blue:arc4random_uniform(256)/255.0 alpha:1.0]];
[scrollView setMaximumZoomScale:2.5f];
[scrollView setMinimumZoomScale:0.5f];
[scrollView setZoomScale:scrollView.minimumZoomScale];
return scrollView;
}
#pragma mark - UIScrollViewDelegate
-(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
return self.imageView;
}
因为它正在显示图像而我可以滚动。为什么我无法放大或缩小？
答案 0 :(得分：1)
您必须为滚动视图指定一个委托，然后实施[SetUp]
public void SetUp()
{
// setup only for cases where obj.Number == 1
_service
.Setup(x => x.ProcessInt(It.Is<MyObj>(o => o.Number == 1 )))
.Returns(1);
// setup only for cases where obj.Number == 2
_service
.Setup(x => x.ProcessInt(It.Is<MyObj>(o => o.Number == 2 )))
.Returns(2);
}
告诉它缩放图像视图：
viewForZoomingInScrollView然后使用图片视图填充这些可缩放的滚动视图，- (UIView *)addScrollViewWithImageView {
UIScrollView *scrollView = [[UIScrollView alloc] init];
scrollView.translatesAutoresizingMaskIntoConstraints = false;
scrollView.maximumZoomScale = 200.0;
scrollView.minimumZoomScale = 0.1;
scrollView.delegate = self;
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"test.png"]];
imageView.translatesAutoresizingMaskIntoConstraints = false;
[self.view addSubview:scrollView];
[scrollView addSubview:imageView];
[NSLayoutConstraint activateConstraints:@[
[imageView.topAnchor constraintEqualToAnchor:scrollView.topAnchor],
[imageView.leftAnchor constraintEqualToAnchor:scrollView.leftAnchor],
[imageView.rightAnchor constraintEqualToAnchor:scrollView.rightAnchor],
[imageView.bottomAnchor constraintEqualToAnchor:scrollView.bottomAnchor]
]];
return scrollView;
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return scrollView.subviews.firstObject;
}
可能如下所示：
viewDidLoad答案 1 :(得分：0)
尝试MWPhotoBrowser。它内置了滚动和缩放功能。你会得到比你需要的更多。祝你好运。