我正在開發(fā)一個(gè)應(yīng)用程序，UIImages通過使用來顯示的畫廊UIScrollView，我的問題是，如何點(diǎn)按zoom并雙擊以zoom退出，使用處理時(shí)它是如何工作的UIScrollView。
2 回答
慕標(biāo)琳琳
TA貢獻(xiàn)1830條經(jīng)驗(yàn) 獲得超9個(gè)贊
您需要實(shí)現(xiàn)UITapGestureRecognizer -文檔在這里 -在你的viewController
- (void)viewDidLoad
{
[super viewDidLoad];
// what object is going to handle the gesture when it gets recognised ?
// the argument for tap is the gesture that caused this message to be sent
UITapGestureRecognizer *tapOnce = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapOnce:)];
UITapGestureRecognizer *tapTwice = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapTwice:)];
// set number of taps required
tapOnce.numberOfTapsRequired = 1;
tapTwice.numberOfTapsRequired = 2;
// stops tapOnce from overriding tapTwice
[tapOnce requireGestureRecognizerToFail:tapTwice];
// now add the gesture recogniser to a view
// this will be the view that recognises the gesture
[self.view addGestureRecognizer:tapOnce];
[self.view addGestureRecognizer:tapTwice];
}
基本上，這段代碼是說，UITapGesture在self.view方法中注冊(cè)a時(shí)，將調(diào)用tapOnce或tapTwice，self具體取決于它是單擊還是雙擊。因此，您需要將以下tap方法添加到您的UIViewController：
- (void)tapOnce:(UIGestureRecognizer *)gesture
{
//on a single tap, call zoomToRect in UIScrollView
[self.myScrollView zoomToRect:rectToZoomInTo animated:NO];
}
- (void)tapTwice:(UIGestureRecognizer *)gesture
{
//on a double tap, call zoomToRect in UIScrollView
[self.myScrollView zoomToRect:rectToZoomOutTo animated:NO];
}
希望能有所幫助
慕斯王
TA貢獻(xiàn)1864條經(jīng)驗(yàn) 獲得超2個(gè)贊
Swift 3.0版本，雙擊可放大兩次。
@IBOutlet weak var scrollView: UIScrollView!
@IBOutlet weak var imageView: UIImageView!
某個(gè)地方（通常在viewDidLoad中）：
let tapRecognizer = UITapGestureRecognizer(target: self, action: #selector(onDoubleTap(gestureRecognizer:)))
tapRecognizer.numberOfTapsRequired = 2
scrollView.addGestureRecognizer(tapRecognizer)
處理程序：
func onDoubleTap(gestureRecognizer: UITapGestureRecognizer) {
let scale = min(scrollView.zoomScale * 2, scrollView.maximumZoomScale)
if scale != scrollView.zoomScale {
let point = gestureRecognizer.location(in: imageView)
let scrollSize = scrollView.frame.size
let size = CGSize(width: scrollSize.width / scale,
height: scrollSize.height / scale)
let origin = CGPoint(x: point.x - size.width / 2,
y: point.y - size.height / 2)
scrollView.zoom(to:CGRect(origin: origin, size: size), animated: true)
print(CGRect(origin: origin, size: size))
}
}
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