touchesBegan, touchesEnded, touchesMoved for moving uivi

je suggère d'utiliser un UIPanGestureRecognizer:

-(void)dragging:(UIPanGestureRecognizer *)gesture
{
    // Check if this is the first touch
    if(gesture.state == UIGestureRecognizerStateBegan)
    {
        // Store the initial touch so when we change positions we do not snap
        self.panCoord = [gesture locationInView:gesture.view];
        [self.view bringSubviewToFront:gesture.view];

    }

    CGPoint newCoord = [gesture locationInView:gesture.view];

    // Create the frame offsets to use our finger position in the view.
    float dX = newCoord.x-self.panCoord.x;
    float dY = newCoord.y-self.panCoord.y;

    gesture.view.frame = CGRectMake(gesture.view.frame.origin.x+dX,
                                    gesture.view.frame.origin.y+dY,
                                    gesture.view.frame.size.width, 
                                    gesture.view.frame.size.height);
}

ce n'est qu'une de mes préférences. Pour moi, il est beaucoup plus simple d'utiliser un reconnaisseur de geste que d'utiliser touchesBegan, touchesEnded,touchesMoved. Je vais les utiliser dans les cas où le UIPanGestureRecognizer ne fonctionne pas.

Ceci est le code de travail pour déplacer les objets UIView

float oldX, oldY; BOOL dragging;

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:touch.view];
    if ([[touch.view class] isSubclassOfClass:[UILabel class]]) {
        dragging = YES;
        oldX = touchLocation.x;
        oldY = touchLocation.y;
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    dragging = NO;
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:touch.view];    
    if ([[touch.view class] isSubclassOfClass:[UILabel class]]) {
        UILabel *label = (UILabel *)touch.view;
        if (dragging) {
            CGRect frame = label.frame;
            frame.origin.x = label.frame.origin.x + touchLocation.x - oldX;
            frame.origin.y = label.frame.origin.y + touchLocation.y - oldY;
            label.frame = frame;
        }
    }
}

avec ce code, je peux déplacer mon objet uivi n'importe où. Mon ViewController.swift ressemble à ça.

// code from below

import UIKit

class ViewController: UIViewController {

    var location = CGPoint(x: 0, y: 0)

    @IBOutlet weak var Person: UIImageView!

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

        var touch : UITouch! =  touches.first! as UITouch

        location = touch.location(in: self.view)

        Person.center = location

    }

    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {

        var touch : UITouch! =  touches.first! as UITouch

        location = touch.location(in: self.view)

        Person.center = location
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        Person.center = CGPoint(x: 160, y: 330)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}

//ends

espérons que cela aide bien que ce soit une autre façon de le faire que celle mentionnée en question.