iOS中间透明周围不透明(镂空)方法实现特种进度条

前言

最近由于要给APP更新UI，然后UIDesigner为了"尝鲜",给我一些新的界面设计，所以我这里也不得不再来造些另外的轮子。如果对您有帮助，麻烦Github给个star

如果有兴趣的，可以移步iOS UIBezierPath绘图相关问题,里边一些遇到的问题的详细的总结

这里先来看下今天要造的轮子

效果图

没错，就是上边的进度条。

实现

先说下思路（采用的是使用MASK遮罩，然后改变底层OrangeColorLayer长度，以达到进度条长度变化的思路）
1. 首先，我们创建一个新的类，继承自UIView,然后，我们采用Core Graphics框架和UIBezierPath类来实现中间的进度条样式。先来分析下进度条，可以看出来，进度条内部，有两种颜色：橙色的TintColor，DarkGray的进度达不到的进度条颜色，然后，进度条背景色lightDarkColor,和最上层圆形中的小圆点。
2. 我这里的进度条，实现发方法是采用4层layer来实现：最底层，绘制DarkGray颜色的进度条，再往上一层，设置有颜色的一层layer,通过改变该层layer的宽度，已达到有颜色进度条的长度变化，再上层，是一个中间进度条轮廓透明，周围是lightGrayColor背景色的遮罩View,最上层，是几个进度条内部小圆的layer。采用的是使用MASK遮罩，然后改变底层OrangeColorLayer长度，以达到进度条长度变化的思路

这里代码
1.先看下暴露出来的API接口
```
@interface RRMyMaterialProgressBar : UIView
//一共项数
//@property (nonatomic,assign) CGFloat totalStepsCounts;

@property (nonatomic,strong) CAShapeLayer *firstArc;

@property (nonatomic,strong) CAShapeLayer *secondArc;

@property (nonatomic,strong) CAShapeLayer *thirdArc;

@property (nonatomic,strong) CAShapeLayer *forthArc;

//当前进度
@property (nonatomic,assign) CGFloat currentPercentage;
//渲染颜色
//@property (nonatomic,strong) UIColor *progressBarTintColor;

- (instancetype)initWithFrame:(CGRect)frame totalStepsCounts:(CGFloat)steps progressBarTintColor:(UIColor *)tintClr;

@end
      ```

PS：

这里是有一些问题的，最开始的时候，我是在drawRect方法中实现的，然后把总共的圆形个数，和进度条的渲染颜色都作为了外部属性，也是能实现的，但是：有些问题：考虑下我们的使用场景：一般我们都是在外层VC的viewWillAppear或者viewDidLoad方法中设置这个progressBar的进度，但是！如果在drawRect方法中实现的话，此时，内部的各个layer都还没有初始化，全部都是nil，如果在viewDidAppear方法中设置的话，会有一个BUG：刚进到页面内的时候，会看到进度条的进度是100%的，（因为默认创建ColorLayer的时候是设置的整个Frame的）,然后，调用外层viewDidAppear方法设置进度条的进度Layer长度，此时，进度条才会又从头开始显示。这么一来，用户体验就不是太好了。

所以，我又优化了一下：progressBarView 初始化的时候，就来绘制这些内层layer,以此来保证外部VC调用viewWillAppear或者viewDidLoad方法的时候，内层progressBar内的各个实例都已经ALLOC,并且可以设置他们。(所以，以前的totalStepsCounts和progressBarTintColor都可以设置为私有变量),然后我们直接在初始化方法中传入参数以赋值。

#import "RRMyMaterialProgressBar.h"

@interface RRMyMaterialProgressBar()

@property (nonatomic,strong) CALayer *backColorLayer;

@property (nonatomic,strong) CAShapeLayer *middleDarkArcLayer;

@property (nonatomic,strong) CAShapeLayer *foregroundMaskLayer;


//渲染颜色
@property (nonatomic,strong) UIColor *progressBarTintColor;

//上一次的比例
@property (nonatomic,assign) CGFloat lastPercentage;

//一共项数
@property (nonatomic,assign) CGFloat totalStepsCounts;

@end

@implementation RRMyMaterialProgressBar

- (instancetype)initWithFrame:(CGRect)frame totalStepsCounts:(CGFloat)steps progressBarTintColor:(UIColor *)tintClr{
    if (self == [super initWithFrame:frame]) {
        self.progressBarTintColor = tintClr;
        self.totalStepsCounts = steps;
        [self setupSubLayersWithFrame:frame];
    }
    return self;
}


- (void)setupSubLayersWithFrame:(CGRect)rect {
    self.layer.backgroundColor = [UIColor redColor].CGColor;
    
    //左右两侧的距离
    CGFloat padding = 10.f;
    //外圆的半径
    CGFloat arcRadius = 7.f;
    //中间线的线宽
    CGFloat middleLineWidth = 1.f;
    //内层圆按钮半径
    CGFloat innerArcRadius = 4.f;
    CGFloat viewWidth = rect.size.width;
    CGFloat viewHeight = rect.size.height;
    
    
    double arcSinValue = middleLineWidth/arcRadius;
    double radian = asin(arcSinValue);
    
    double tanValue = tan(radian);
    
    CGFloat arcTanLength = middleLineWidth/tanValue;
    
    CGFloat middleLineDistance = (viewWidth - 2 * padding - arcRadius * 2 - (self.totalStepsCounts * 2 - 2) * arcTanLength)/(self.totalStepsCounts - 1);
    
    
    self.middleDarkArcLayer = [CAShapeLayer layer];
    UIBezierPath *middleDrakColorPath = [UIBezierPath bezierPath];
    [middleDrakColorPath moveToPoint:CGPointMake(padding, viewHeight/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius, viewHeight/2) radius:arcRadius startAngle:M_PI endAngle:2*M_PI - radian clockwise:YES];
    [middleDrakColorPath addLineToPoint:CGPointMake(padding + arcRadius +arcTanLength + middleLineDistance, viewHeight/2 - middleLineWidth/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius +arcTanLength * 2 + middleLineDistance, viewHeight/2) radius:arcRadius startAngle:M_PI + radian endAngle:2 * M_PI - radian clockwise:YES];
    [middleDrakColorPath addLineToPoint:CGPointMake(padding + arcRadius + 3 * arcTanLength + middleLineDistance * 2, viewHeight/2 - middleLineWidth/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius + 4 * arcTanLength + middleLineDistance * 2, viewHeight/2) radius:arcRadius startAngle:M_PI + radian endAngle:2 * M_PI - radian clockwise:YES];
    [middleDrakColorPath addLineToPoint:CGPointMake(padding + arcRadius + 5 * arcTanLength + middleLineDistance * 3, viewHeight/2 - middleLineWidth/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius + 6 * arcTanLength + middleLineDistance * 3, viewHeight/2) radius:arcRadius startAngle:M_PI + radian endAngle:3 * M_PI - radian clockwise:YES];
    [middleDrakColorPath addLineToPoint:CGPointMake(padding + arcRadius + 5 * arcTanLength + middleLineDistance * 2, viewHeight/2 + middleLineWidth/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius + 4 * arcTanLength + middleLineDistance * 2, viewHeight/2) radius:arcRadius startAngle:radian endAngle:M_PI - radian clockwise:YES];
    [middleDrakColorPath addLineToPoint:CGPointMake(padding + arcRadius + 3 * arcTanLength + middleLineDistance, viewHeight/2 + middleLineWidth/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius + 2 * arcTanLength + middleLineDistance, viewHeight/2) radius:arcRadius startAngle:radian endAngle:M_PI - radian clockwise:YES];
    [middleDrakColorPath addLineToPoint:CGPointMake(padding + arcRadius + arcTanLength, viewHeight/2 + middleLineWidth/2)];
    [middleDrakColorPath addArcWithCenter:CGPointMake(padding + arcRadius, viewHeight/2) radius:arcRadius startAngle:radian endAngle:M_PI - radian clockwise:YES];
    [middleDrakColorPath closePath];
    
    self.middleDarkArcLayer.fillColor = RGB(203, 204, 205).CGColor;
    self.middleDarkArcLayer.path = middleDrakColorPath.CGPath;
    [self.layer addSublayer:self.middleDarkArcLayer];
    
    
    //MARK: 颜色层layer
    self.backColorLayer = [CALayer layer];
    self.backColorLayer.frame = CGRectMake(0, 0, viewWidth, viewHeight);
    self.backColorLayer.backgroundColor = self.progressBarTintColor.CGColor;
    self.backColorLayer.position = CGPointMake(0, viewHeight/2);
    self.backColorLayer.anchorPoint = CGPointMake(0, 0.5);
    [self.layer addSublayer:self.backColorLayer];
    
    
    self.foregroundMaskLayer = [CAShapeLayer layer];
    //MARK: 使用UIBezierPath 绘制遮挡VIEW的路径
    UIBezierPath *outerPath = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0,0, rect.size.width, rect.size.height) cornerRadius:rect.size.height/2];
    
    UIBezierPath *colorPath = [UIBezierPath bezierPath];
    [colorPath moveToPoint:CGPointMake(padding, viewHeight/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius, viewHeight/2) radius:arcRadius startAngle:M_PI endAngle:2*M_PI - radian clockwise:YES];
    [colorPath addLineToPoint:CGPointMake(padding + arcRadius +arcTanLength + middleLineDistance, viewHeight/2 - middleLineWidth/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius +arcTanLength * 2 + middleLineDistance, viewHeight/2) radius:arcRadius startAngle:M_PI + radian endAngle:2 * M_PI - radian clockwise:YES];
    [colorPath addLineToPoint:CGPointMake(padding + arcRadius + 3 * arcTanLength + middleLineDistance * 2, viewHeight/2 - middleLineWidth/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius + 4 * arcTanLength + middleLineDistance * 2, viewHeight/2) radius:arcRadius startAngle:M_PI + radian endAngle:2 * M_PI - radian clockwise:YES];
    [colorPath addLineToPoint:CGPointMake(padding + arcRadius + 5 * arcTanLength + middleLineDistance * 3, viewHeight/2 - middleLineWidth/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius + 6 * arcTanLength + middleLineDistance * 3, viewHeight/2) radius:arcRadius startAngle:M_PI + radian endAngle:3 * M_PI - radian clockwise:YES];
    [colorPath addLineToPoint:CGPointMake(padding + arcRadius + 5 * arcTanLength + middleLineDistance * 2, viewHeight/2 + middleLineWidth/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius + 4 * arcTanLength + middleLineDistance * 2, viewHeight/2) radius:arcRadius startAngle:radian endAngle:M_PI - radian clockwise:YES];
    [colorPath addLineToPoint:CGPointMake(padding + arcRadius + 3 * arcTanLength + middleLineDistance, viewHeight/2 + middleLineWidth/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius + 2 * arcTanLength + middleLineDistance, viewHeight/2) radius:arcRadius startAngle:radian endAngle:M_PI - radian clockwise:YES];
    [colorPath addLineToPoint:CGPointMake(padding + arcRadius + arcTanLength, viewHeight/2 + middleLineWidth/2)];
    [colorPath addArcWithCenter:CGPointMake(padding + arcRadius, viewHeight/2) radius:arcRadius startAngle:radian endAngle:M_PI - radian clockwise:YES];
    
    [outerPath appendPath:colorPath];
    [outerPath setUsesEvenOddFillRule:YES];
    
    
    self.foregroundMaskLayer.path = outerPath.CGPath;
    self.foregroundMaskLayer.fillRule = kCAFillRuleEvenOdd;
    self.foregroundMaskLayer.fillColor = RGB(221, 221, 221).CGColor;
    [self.layer addSublayer:self.foregroundMaskLayer];
    
    //MARK: 第一个内部圆
    self.firstArc = [CAShapeLayer layer];
    UIBezierPath *arcPath1 = [UIBezierPath bezierPath];
    [arcPath1 addArcWithCenter:CGPointMake(padding + arcRadius, viewHeight/2) radius:innerArcRadius startAngle:0 endAngle:2 * M_PI clockwise:1];
    self.firstArc.path = arcPath1.CGPath;
    self.firstArc.fillColor = RGB(221, 221, 221).CGColor;
    [self.layer addSublayer:self.firstArc];
    
    
    //MARK: 第二个内部圆
    self.secondArc = [CAShapeLayer layer];
    UIBezierPath *arcPath2 = [UIBezierPath bezierPath];
    [arcPath2 addArcWithCenter:CGPointMake(padding + arcRadius + arcTanLength + middleLineDistance + arcTanLength, viewHeight/2) radius:innerArcRadius startAngle:0 endAngle:2 * M_PI clockwise:1];
    self.secondArc.path = arcPath2.CGPath;
    self.secondArc.fillColor = RGB(221, 221, 221).CGColor;
    [self.layer addSublayer:self.secondArc];
    
    
    //MARK: 第三个内部圆
    self.thirdArc = [CAShapeLayer layer];
    UIBezierPath *arcPath3 = [UIBezierPath bezierPath];
    [arcPath3 addArcWithCenter:CGPointMake(padding + arcRadius + arcTanLength + middleLineDistance + arcTanLength + arcTanLength + middleLineDistance + arcTanLength, viewHeight/2) radius:innerArcRadius startAngle:0 endAngle:2 * M_PI clockwise:1];
    self.thirdArc.path = arcPath3.CGPath;
    self.thirdArc.fillColor = RGB(221, 221, 221).CGColor;
    [self.layer addSublayer:self.thirdArc];
    
    
    //MARK: 第四个内部圆
    self.forthArc = [CAShapeLayer layer];
    UIBezierPath *arcPath4 = [UIBezierPath bezierPath];
    [arcPath4 addArcWithCenter:CGPointMake(padding + arcRadius + arcTanLength + middleLineDistance + arcTanLength + arcTanLength + middleLineDistance + arcTanLength + arcTanLength + middleLineDistance + arcTanLength, viewHeight/2) radius:innerArcRadius startAngle:0 endAngle:2 * M_PI clockwise:1];
    self.forthArc.path = arcPath4.CGPath;
    self.forthArc.fillColor = RGB(221, 221, 221).CGColor;
    [self.layer addSublayer:self.forthArc];
}


- (void)setCurrentPercentage:(CGFloat)currentPercentage {
    _currentPercentage = currentPercentage;
    
    CABasicAnimation *animate = [CABasicAnimation animationWithKeyPath:@"transform.scale.x"];
    animate.fromValue = self.lastPercentage == 0 ? @(0) : @(self.lastPercentage);        
    animate.toValue = @(currentPercentage);
    animate.repeatCount = 1;
    animate.autoreverses = NO;
    animate.duration = 1.f;
    animate.removedOnCompletion = NO;
    animate.fillMode = kCAFillModeForwards;
    [self.backColorLayer addAnimation:animate forKey:@"progressAnimation"];
    
    self.lastPercentage = currentPercentage;

}

另外

整个进度条并不是圆形是环形的，如果有UI需求，我们可以通过设置API接口中的四个shapeLayer的fillColor值来改变内部小圆的颜色的

self.forthArc.fillColor = [UIColor yourWantedColor].CGColor;

这里有些参考资料
都是关于view中间镂空周围不是空的

最后编辑于：2018.05.24 13:17:53

人面猴
序言：七十年代末，一起剥皮案震惊了整个滨河市，随后出现的几起案子，更是在滨河造成了极大的恐慌，老刑警刘岩，带你破解...
沈念sama阅读 194,457评论 5赞 459
死咒
序言：滨河连续发生了三起死亡事件，死亡现场离奇诡异，居然都是意外死亡，警方通过查阅死者的电脑和手机，发现死者居然都...
沈念sama阅读 81,837评论 2赞 371
救了他两次的神仙让他今天三更去死
文/潘晓璐我一进店门，熙熙楼的掌柜王于贵愁眉苦脸地迎上来，“玉大人，你说我怎么就摊上这事。” “怎么了？”我有些...
开封第一讲书人阅读 141,696评论 0赞 319
道士缉凶录：失踪的卖姜人
文/不坏的土叔我叫张陵，是天一观的道长。经常有香客问我，道长，这世上最难降的妖魔是什么？我笑而不...
开封第一讲书人阅读 52,183评论 1赞 263
港岛之恋（遗憾婚礼）
正文为了忘掉前任，我火速办了婚礼，结果婚礼上，老公的妹妹穿的比我还像新娘。我一直安慰自己，他们只是感情好，可当我...
茶点故事阅读 61,057评论 4赞 355
恶毒庶女顶嫁案：这布局不是一般人想出来的
文/花漫我一把揭开白布。她就那样静静地躺着，像睡着了一般。火红的嫁衣衬着肌肤如雪。梳的纹丝不乱的头发上，一...
开封第一讲书人阅读 46,105评论 1赞 272
城市分裂传说
那天，我揣着相机与录音，去河边找鬼。笑死，一个胖子当着我的面吹牛，可吹牛的内容都是我干的。我是一名探鬼主播，决...
沈念sama阅读 36,520评论 3赞 381
双鸳鸯连环套：你想象不到人心有多黑
文/苍兰香墨我猛地睁开眼，长吁一口气：“原来是场噩梦啊……” “哼！你这毒妇竟也来了？” 一声冷哼从身侧响起，我...
开封第一讲书人阅读 35,211评论 0赞 253
万荣杀人案实录
序言：老挝万荣一对情侣失踪，失踪者是张志新（化名）和其女友刘颖，没想到半个月后，有当地人在树林里发现了一具尸体，经...
沈念sama阅读 39,482评论 1赞 290
护林员之死
正文独居荒郊野岭守林人离奇死亡，尸身上长有42处带血的脓包…… 初始之章·张勋以下内容为张勋视角年9月15日...
茶点故事阅读 34,574评论 2赞 309
白月光启示录
正文我和宋清朗相恋三年，在试婚纱的时候发现自己被绿了。大学时的朋友给我发了我未婚夫和他白月光在一起吃饭的照片。...
茶点故事阅读 36,353评论 1赞 326
活死人
序言：一个原本活蹦乱跳的男人离奇死亡，死状恐怖，灵堂内的尸体忽然破棺而出，到底是诈尸还是另有隐情，我是刑警宁泽，带...
沈念sama阅读 32,213评论 3赞 312
日本核电站爆炸内幕
正文年R本政府宣布，位于F岛的核电站，受9级特大地震影响，放射性物质发生泄漏。R本人自食恶果不足惜，却给世界环境...
茶点故事阅读 37,576评论 3赞 298
男人毒药：我在死后第九天来索命
文/蒙蒙一、第九天我趴在偏房一处隐蔽的房顶上张望。院中可真热闹，春花似锦、人声如沸。这庄子的主人今日做“春日...
开封第一讲书人阅读 28,897评论 0赞 17
一桩弑父案，背后竟有这般阴谋
文/苍兰香墨我抬头看了看天上的太阳。三九已至，却和暖如春，着一层夹袄步出监牢的瞬间，已是汗流浃背。一阵脚步声响...
开封第一讲书人阅读 30,174评论 1赞 250
情欲美人皮
我被黑心中介骗来泰国打工，没想到刚下飞机就差点儿被人妖公主榨干…… 1. 我叫王不留，地道东北人。一个月前我还...
沈念sama阅读 41,489评论 2赞 341
代替公主和亲
正文我出身青楼，却偏偏与公主长得像，于是被迫代替她去往敌国和亲。传闻我的和亲对象是个残疾皇子，可洞房花烛夜当晚...
茶点故事阅读 40,683评论 2赞 335

iOS中间透明周围不透明(镂空)方法实现特种进度条

前言

实现

PS：

另外

推荐阅读更多精彩内容