扩展UIButton的点击区域

#import "UIButton+EnlargeEdge.h"
#import <objc/runtime.h>

#define keyTopEdge  @"keyTopEdge"
#define keyleftEdge  @"keyTopEdge"
#define keybottomEdge  @"keyTopEdge"
#define keyrightEdge  @"keyTopEdge"

@implementation UIButton (EnlargeEdge)

- (void)setEnlargeEdge:(CGFloat) size
{
    objc_setAssociatedObject(self, keyTopEdge, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
    objc_setAssociatedObject(self, keyleftEdge, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
    objc_setAssociatedObject(self, keybottomEdge, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
    objc_setAssociatedObject(self, keyrightEdge, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
}

- (void)setEnlargeEdgeWithTop:(CGFloat) top right:(CGFloat) right bottom:(CGFloat) bottom left:(CGFloat) left
{
    objc_setAssociatedObject(self, keyTopEdge, [NSNumber numberWithFloat:top], OBJC_ASSOCIATION_COPY_NONATOMIC);
    objc_setAssociatedObject(self, keyleftEdge, [NSNumber numberWithFloat:right], OBJC_ASSOCIATION_COPY_NONATOMIC);
    objc_setAssociatedObject(self, keybottomEdge, [NSNumber numberWithFloat:bottom], OBJC_ASSOCIATION_COPY_NONATOMIC);
    objc_setAssociatedObject(self, keyrightEdge, [NSNumber numberWithFloat:left], OBJC_ASSOCIATION_COPY_NONATOMIC);
}

//使用bounds来增大点击区域
- (CGRect)enlargedRect
{
    NSNumber* topEdge = objc_getAssociatedObject(self, keyTopEdge);
    NSNumber* leftEdge = objc_getAssociatedObject(self, keyleftEdge);
    NSNumber* bottomEdge = objc_getAssociatedObject(self, keybottomEdge);
     NSNumber* rightEdge = objc_getAssociatedObject(self, keyrightEdge);
    
    if (topEdge && rightEdge && bottomEdge && leftEdge)
    {
        return CGRectMake(self.bounds.origin.x - leftEdge.floatValue,
                          self.bounds.origin.y - topEdge.floatValue,
                          self.bounds.size.width + leftEdge.floatValue + rightEdge.floatValue,
                          self.bounds.size.height + topEdge.floatValue + bottomEdge.floatValue);
    }
    else
    {
        return self.bounds;
    }
}
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
    CGRect rect = [self enlargedRect];
    if (CGRectEqualToRect(rect, self.bounds))
    {
        return [super pointInside:point withEvent:event];
    }
    return CGRectContainsPoint(rect, point) ? YES : NO;
}
@end