Pan over CAShapeLayers and determine which one is panned on

gistfile1.m

//
//  TriangleWrapper.m
//  dot
//
//  Created by LOANER on 3/10/15.
//  Copyright (c) 2015 Thomas Degry. All rights reserved.
//

#import "TriangleWrapper.h"

@interface TriangleWrapper()
@property (assign, nonatomic) CGFloat radius;
@property (assign, nonatomic) NSInteger numberOfItems;
@property (strong, nonatomic) NSMutableArray *layers;
@end

@implementation TriangleWrapper

- (instancetype)initWithFrame:(CGRect)frame radius:(CGFloat)radius andNumberOfItems:(NSInteger)numberOfItems {
    self = [super initWithFrame:frame];
    if (self) {
        self.radius = radius;
        self.numberOfItems = numberOfItems;
        
        UIPanGestureRecognizer *gesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panned:)];
        gesture.maximumNumberOfTouches = 1;
        gesture.minimumNumberOfTouches = 1;
        [self addGestureRecognizer:gesture];
    }
    
    return self;
}

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {
    return YES;
}

- (void)panned:(UIPanGestureRecognizer *)gesture {
    CGPoint point = [gesture locationInView:self];

    for (NSInteger i = 0; i < [self.layer.sublayers count]; i++) {
        
        CAShapeLayer *currentLayer = (CAShapeLayer *)self.layer.sublayers[i];
        if (CGPathContainsPoint(currentLayer.path, NULL, point, NO)) {
            NSLog(@"Swiping over layer with name %@", currentLayer.name);
        }
    }
}


// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
    [super drawRect:rect];
    
    CGPoint center = self.center;
    
    for (NSInteger i = 0; i < self.numberOfItems; i++) {
        CGPoint point1 = CGPointMake(center.x + self.radius * sinf(2 * (i - 0.5) * M_PI / self.numberOfItems),
                                     center.y + self.radius * -cosf(2 * (i - 0.5) * M_PI / self.numberOfItems));
        
        CGPoint point2 = CGPointMake(center.x + self.radius * sinf(2 * (i + 0.5) * M_PI / self.numberOfItems),
                                     center.y + self.radius * -cosf(2 * (i + 0.5) * M_PI / self.numberOfItems));
        
        UIBezierPath* trianglePath = [UIBezierPath bezierPath];
        [trianglePath moveToPoint:CGPointMake(center.x, center.y)];
        [trianglePath addLineToPoint:CGPointMake(point1.x, point1.y)];
        [trianglePath addLineToPoint:CGPointMake(point2.x, point2.y)];
        [trianglePath closePath];
        
        CGFloat hue = ( arc4random() % 256 / 256.0 );  //  0.0 to 1.0
        CGFloat saturation = ( arc4random() % 128 / 256.0 ) + 0.5;  //  0.5 to 1.0, away from white
        CGFloat brightness = ( arc4random() % 128 / 256.0 ) + 0.5;  //  0.5 to 1.0, away from black
        UIColor *color = [UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];
        
        CAShapeLayer *triangle = [CAShapeLayer layer];
        triangle.fillColor = color.CGColor;
        triangle.name = [NSString stringWithFormat:@"triange%li", (long)i];
        [triangle setPath:trianglePath.CGPath];
        [self.layer addSublayer:triangle];
    }

}


@end