首先创建一个StarView

#import "StarView.h"

@implementation StarView
{
    UIImageView * _foregroundImageView;// 前景图
    UIImageView * _backgroundImageView; // 背景图
}

// 创建视图
- (void)createViews
{
    _backgroundImageView = [[UIImageView alloc] init];
    [self addSubview:_backgroundImageView];
    // 自动布局
    _backgroundImageView.translatesAutoresizingMaskIntoConstraints = NO;
    [_backgroundImageView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(self);
        make.top.equalTo(self);
        make.width.equalTo(@46);
        make.height.equalTo(@12);
    }];
    // 设置背景图属性
    _backgroundImageView.image = [UIImage imageNamed:@"star_gray"];
    // 设置图片显示模式
    _backgroundImageView.contentMode = UIViewContentModeLeft;
    
    // 前景图
    _foregroundImageView = [[UIImageView alloc]
                            initWithImage:[UIImage imageNamed:@"star_hight"]];
    [self addSubview:_foregroundImageView];
    [_foregroundImageView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.edges.equalTo(_backgroundImageView);
    }];
    // 设置图片显示模式
    _foregroundImageView.contentMode = UIViewContentModeLeft;
    // 裁剪
    _foregroundImageView.clipsToBounds = YES;
}

// 重写init方法
- (instancetype)initWithFrame:(CGRect)frame
{
    if (self = [super initWithFrame:frame]) {
        [self createViews];
    }
    return self;
}

// 当在Xib或者Storyboard中关联类时，程序从xib或者storyboard创建对象时，会调用该方法
- (instancetype)initWithCoder:(NSCoder *)aDecoder
{
    if (self = [super initWithCoder:aDecoder]) {
        [self createViews];
    }
    return self;
}
-(void)setStarValue:(CGFloat)starValue
{
    _starValue = starValue;
    if (_starValue >= 0 && _starValue <= 5)
    {
        // 重建约束
        [_foregroundImageView mas_remakeConstraints:^(MASConstraintMaker *make) {
            make.left.equalTo(_backgroundImageView);
            make.top.equalTo(_backgroundImageView);
            make.height.equalTo(_backgroundImageView);
            make.width.equalTo(_backgroundImageView).multipliedBy(_starValue/5);
        }];
    }
    
//    NSLog(@"starValue is %0.1f",_starValue/5);
}

#import <UIKit/UIKit.h>

@interface StarView : UIView

@property (nonatomic, assign) CGFloat starValue; // 星标的值
@end

最后在要显示星级评价的界面将其带入

/**星级*/
    // 设置星标的值
    self.calenderStartView.starValue =[_calendarModel.star floatValue];

最后来一张显示图

IMG_1688.PNG