Jak stuknąć, aby powiększyć i stuknąć dwukrotnie, aby pomniejszyć system iOS?
Rozwijam aplikację do wyświetlania galerii UIImages
za pomocą UIScrollView
, moje pytanie brzmi, jak stuknąć do zoom
i dwukrotnie stuknąć do zoom
out, Jak to działa podczas obsługi z UIScrollView
.
21
2 answers
Musisz zaimplementować UITapGestureRecognizer-docs tutaj - w twoim 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];
}
Zasadniczo ten kod mówi, że gdy {[2] } jest zarejestrowany w self.view
metoda tapOnce lub taptvice zostanie wywołana w self
w zależności od tego, czy jest to pojedynczy czy podwójny kraniec. Dlatego musisz dodać te metody tap do swojego 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];
}
Hope that helps
39
Author: Gaz_Edge,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2015-09-03 20:44:36
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2015-09-03 20:44:36
Wersja Swift 4.0 , która powiększa dwukrotnie przy podwójnym dotknięciu.
@IBOutlet weak var scrollView: UIScrollView!
@IBOutlet weak var imageView: UIImageView!
Gdzieś (zwykle w viewDidLoad):
let tapRecognizer = UITapGestureRecognizer(target: self, action: #selector(onDoubleTap(gestureRecognizer:)))
tapRecognizer.numberOfTapsRequired = 2
scrollView.addGestureRecognizer(tapRecognizer)
:
@objc 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))
}
}
2
Author: Avt,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2020-06-22 07:15:48
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2020-06-22 07:15:48