UIGestureRecognizer is only added for subView but it is also working on parentView?

Question

Here is my code :

[super viewDidLoad];
    UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapGestureRecognizer:)];
    [self.colorView setUserInteractionEnabled:YES];
    [self.colorView addGestureRecognizer:tapGesture];

-(void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{

    UITouch *touch = [[event allTouches] anyObject];
    touchPoint = [touch locationInView:self.colorView];
    UIBezierPath *path = [UIBezierPath bezierPath];
    [path moveToPoint:CGPointMake(touchPoint.x,touchPoint.y)];
    [path addLineToPoint:CGPointMake(startingPoint.x,startingPoint.y)];
    startingPoint=touchPoint;
    CAShapeLayer *shapeLayer = [CAShapeLayer layer];
    shapeLayer.path = [path CGPath];
    shapeLayer.strokeColor = [[UIColor blueColor] CGColor];
    shapeLayer.lineWidth = 3.0;
    shapeLayer.fillColor = [[UIColor redColor] CGColor];
    [self.colorView.layer addSublayer:shapeLayer];

    NSLog(@"Touch moving point =x : %f Touch moving point =y : %f", touchPoint.x, touchPoint.y);



}

so it have to only work on the colorView but what happens is ,that touch is working on self.view inside also ,how to solve this .

vien vu · Accepted Answer · 2016-01-09T06:19:37.700

3

You can add:

 self.colorView.clipsToBounds = YES;

It will resolve your issue.

A Boolean value that determines whether subviews are confined to the bounds of the view.

Declaration OBJECTIVE-C @property(nonatomic) BOOL clipsToBounds Discussion Setting this value to YES causes subviews to be clipped to the bounds of the receiver. If set to NO, subviews whose frames extend beyond the visible bounds of the receiver are not clipped. The default value is NO.

Availability Available in iOS 2.0 and later. Link: Reference

So because it's NO. So interaction will extent to super view. When you set to YES. It only work on your subview.

edited Jan 09 '16 at 06:19

answered Jan 09 '16 at 06:10

vien vu

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did you mean `self.colorView.layer.clipsToBounds = YES;`? – NSGangster Jan 09 '16 at 06:12
@vien vu its working but i like to know how its happening – Kishore Kumar Jan 09 '16 at 06:15
@vienvu thanks,now i understood the concept of clipsToBounds – Kishore Kumar Jan 09 '16 at 06:22
@vienvu do you know how to remove that line from view if user touches the reset button ? – Kishore Kumar Jan 09 '16 at 06:29
@KishoreKumar It's another question. But you can try this way. create array save your layer `[self.layerArray addObject:shapeLayer];` and when reset: ` - (IBAction)reset:(id)sender { for (CAShapeLayer *layer in self.layerArray) { [layer removeFromSuperlayer]; } } ` – vien vu Jan 09 '16 at 06:34

score 0 · Answer 2 · answered Jan 09 '16 at 06:04

0

Views track touches that started inside of them even when the touch goes outside their bounds (that's why you can hold a button, drag out and it'll still be selected while you are within a certain distance)

You can use CGRectContainsPoint to only add a point if it's inside the view.

answered Jan 09 '16 at 06:04

EmilioPelaez

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how to add that CGRectContainPoint brother @EmilioPelaez. – Kishore Kumar Jan 09 '16 at 06:06

UIGestureRecognizer is only added for subView but it is also working on parentView?

2 Answers2