在iOS开发中，经常遇到按钮的点击区域太小，无法达到一个良好的交互效果，通过如下方式扩大点击区域：

@interface UIButton (TTExtensions)

@property (nonatomic, assign) UIEdgeInsets hitTestEdgeInsets;

@end

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

@implementation UIButton (TTExtensions)

- (void)setHitTestEdgeInsets:(UIEdgeInsets)hitTestEdgeInsets
{
    NSValue *value = [NSValue valueWithUIEdgeInsets:hitTestEdgeInsets];
    objc_setAssociatedObject(self, @selector(hitTestEdgeInsets), value, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (UIEdgeInsets)hitTestEdgeInsets
{
    NSValue *value = objc_getAssociatedObject(self, @selector(hitTestEdgeInsets));
    if (value) {
        UIEdgeInsets edgeInset = [value UIEdgeInsetsValue];
        return edgeInset;
    }
    
    return UIEdgeInsetsZero;
}

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
    if (UIEdgeInsetsEqualToEdgeInsets(self.hitTestEdgeInsets, UIEdgeInsetsZero) || !self.enabled || self.hidden) {
        return [super pointInside:point withEvent:event];
    }
    
    CGRect relativeFrame = self.bounds;
    CGRect hitFrame = UIEdgeInsetsInsetRect(relativeFrame, self.hitTestEdgeInsets);
    return CGRectContainsPoint(hitFrame, point);
}

@end