UISlider 在 iOS 12 上不好滑动的解决方案

#import "RLKShapeSlider.h"

static const CGFloat kSliderBound = 20.0;

@interface RLKShapeSlider ()

@property (nonatomic) CGRect lastBounds;

@end

@implementation RLKShapeSlider

- (CGRect)trackRectForBounds:(CGRect)bounds {
    return CGRectMake(bounds.origin.x, bounds.origin.y, bounds.size.width, MAX(bounds.size.height, 2.0));
}

- (CGRect)thumbRectForBounds:(CGRect)bounds trackRect:(CGRect)rect value:(float)value;
{

    rect.origin.x = rect.origin.x;
    rect.size.width = rect.size.width;
    CGRect result = [super thumbRectForBounds:bounds trackRect:rect value:value];
    //记录下最终的frame
    _lastBounds = result;
    return result;
}
//检查是点击事件的点是否在slider范围内
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {
    //调用父类判断
    BOOL result = [super pointInside:point withEvent:event];

    if (!result) {
        //如果不在slider范围内，扩充响应范围
        if ((point.x >= (_lastBounds.origin.x - kSliderBound)) &&
            (point.x <= (_lastBounds.origin.x + _lastBounds.size.width + kSliderBound)) &&
            (point.y >= -kSliderBound) &&
            (point.y < kSliderBound)) {
            //在扩充范围内
            return YES;
        }
    }

    //否则返回父类的结果
    return result;
}
@end