使用XIB 或storyboard 进行比例适配

1、给NSLayoutConstraint 添加一个分类

IB_DESIGNABLE
@interface NSLayoutConstraint (Scale)
@property (nonatomic, copy) IBInspectable NSString  *vaule;
@end

#import <objc/runtime.h>
#import "NSLayoutConstraint+Scale.h"
static void *vauleKey = &vauleKey;
@implementation NSLayoutConstraint (Scale)
-(void)setVaule:(NSString *)vaule {
    CGFloat w = [UIScreen mainScreen].bounds.size.width;
    objc_setAssociatedObject(self, vauleKey, vaule, OBJC_ASSOCIATION_ASSIGN);
    self.constant=w/375.0*([vaule floatValue]);
    
}
-(NSString *)vaule{
    
    return objc_getAssociatedObject(self, vauleKey);
}

2、切换到xib或sb 中设置属性

图片.png