iOS UIBezierPath的使用

先来看看我机智的呆呆....做出投篮动作，造台阶一个犯规

OK！进入正题，哈哈

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UIBezierPath简介

从名字上可以看得出这是一个贝塞尔路径，可以绘制直线，曲线，以及各种几何路径，它是基于CoreGraphics中path相关的一个封装，可以直接在drawRect方法中绘制出想要的几何图形，也可以配合CAShapeLayer来展示，待会我会在drawRect里面演示，与CAShapeLayer的配合使用，我之后会用一个更好的实例来演示。

主要的方法

 //创建一个矩形路径
 + (instancetype)bezierPathWithRect:(CGRect)rect;
 //创建一个内切圆或椭圆的路径
 + (instancetype)bezierPathWithOvalInRect:(CGRect)rect;
 //创建一个矩形路径，并设置圆角
 + (instancetype)bezierPathWithRoundedRect:(CGRect)rect cornerRadius:(CGFloat)cornerRadius;
 //创建一个矩形路径，并设置圆角方向，以及圆角大小
 + (instancetype)bezierPathWithRoundedRect:(CGRect)rect byRoundingCorners:(UIRectCorner)corners cornerRadii:(CGSize)cornerRadii;
 //创建一个圆弧路径,参数(`center`：圆心 、`radius`：半径 、`startAngle `：起始角度 、`endAngle `：结束角度 、`clockwise`:YES顺时针/NO逆时针)。
 + (instancetype)bezierPathWithArcCenter:(CGPoint)center radius:(CGFloat)radius startAngle:(CGFloat)startAngle endAngle:(CGFloat)endAngle clockwise:(BOOL)clockwise;


 //去设置初始点
 - (void)moveToPoint:(CGPoint)point;
 //添加直线
 - (void)addLineToPoint:(CGPoint)point;
 //添加三次贝塞尔曲线，两个控制点
 - (void)addCurveToPoint:(CGPoint)endPoint controlPoint1:(CGPoint)controlPoint1 controlPoint2:(CGPoint)controlPoint2;
 //添加二次贝塞尔曲线，一个控制点
 - (void)addQuadCurveToPoint:(CGPoint)endPoint controlPoint:(CGPoint)controlPoint;
 //添加圆弧 
 - (void)addArcWithCenter:(CGPoint)center radius:(CGFloat)radius startAngle:(CGFloat)startAngle endAngle:(CGFloat)endAngle clockwise:(BOOL)clockwise
 //闭合路径，在起点跟终点添加一条直线
 - (void)closePath;
 //路径拼接
 - (void)appendPath:(UIBezierPath *)bezierPath;
 //返回一个与当前路径相反的新的贝塞尔路径对象
 - (UIBezierPath *)bezierPathByReversingPath
 //添加虚线
 - (void)setLineDash:(nullable const CGFloat *)pattern count:(NSInteger)count phase:(CGFloat)phase;
 //去填充所绘制的区域
 - (void)fill;
 //去绘制路径
 - (void)stroke;

属性

//拿到CGPath
@property(nonatomic) CGPathRef CGPath;
//画笔当前的位置
@property(nonatomic,readonly) CGPoint currentPoint;
//线宽
@property(nonatomic) CGFloat lineWidth;
//终点类型
@property(nonatomic) CGLineCap lineCapStyle;
typedef CF_ENUM(int32_t, CGLineCap) {
    kCGLineCapButt,
    kCGLineCapRound,
    kCGLineCapSquare
};
//交叉点类型
@property(nonatomic) CGLineJoin lineJoinStyle;
typedef CF_ENUM(int32_t, CGLineJoin) {
    kCGLineJoinMiter,
    kCGLineJoinRound,
    kCGLineJoinBevel
};
//最大斜接长度，只有lineJoin属性为kCALineJoinMiter时miterLimit才有效
@property(nonatomic) CGFloat miterLimit
//指定even-odd（奇偶）规则是否在path可用，奇数在path内部，偶数在外部，所以path交汇处是偶数，是不会绘制的
@property(nonatomic) BOOL usesEvenOddFillRule; 

举个栗子

- (void)drawRect:(CGRect)rect{
    [[UIColor redColor] setStroke];
    [[UIColor greenColor] setFill];
    //椭圆
    [self addPath:
     [UIBezierPath bezierPathWithRoundedRect:CGRectMake(20, 20, 100, 50) cornerRadius:25]];
    //矩形
    [self addPath:
     [UIBezierPath bezierPathWithRect:CGRectMake(140, 20, 100, 50)]];
    //内切椭圆
    [self addPath:
     [UIBezierPath bezierPathWithOvalInRect:CGRectMake(260, 20, 100, 50)]];

    //换色
    [[UIColor lightGrayColor] setStroke];
    [[UIColor blueColor] setFill];
    //圆
    [self addPath:
     [UIBezierPath bezierPathWithOvalInRect:CGRectMake(20, 90, 100, 100)]];
    //左上右下圆角
    [self addPath:
     [UIBezierPath bezierPathWithRoundedRect:CGRectMake(140, 90, 100, 100) byRoundingCorners:UIRectCornerTopLeft | UIRectCornerBottomRight cornerRadii:CGSizeMake(50, 0)]];
    //圆弧
    UIBezierPath*cPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(310, 140) radius:50 startAngle:M_PI_2 endAngle:0 clockwise:YES];
    cPath.lineWidth = 4;
    [cPath stroke];
    
    //换色
    [[UIColor purpleColor] setStroke];
    [[UIColor orangeColor] setFill];
    //扇形
    UIBezierPath *sPath = [UIBezierPath bezierPath];
    [sPath moveToPoint:CGPointMake(70, 260)];
    [sPath addArcWithCenter:CGPointMake(70, 260) radius:50 startAngle:-M_PI*2/3.f endAngle:-M_PI_4 clockwise:YES];
    [self addPath:sPath];
    [sPath closePath];
    //二次贝塞尔
    UIBezierPath *towPath = [UIBezierPath bezierPath];
    [towPath moveToPoint:CGPointMake(150, 210)];
    [towPath addQuadCurveToPoint:CGPointMake(150, 310) controlPoint:CGPointMake(250, 260)];
    [towPath stroke];
    //三次贝塞尔
    UIBezierPath *trePath = [UIBezierPath bezierPath];
    [trePath moveToPoint:CGPointMake(260, 260)];
    [trePath addCurveToPoint:CGPointMake(360, 260) controlPoint1:CGPointMake(285, 210) controlPoint2:CGPointMake(335, 310)];
    [trePath stroke];
    //交汇圆
    UIBezierPath *yPath = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(20, 330, 100, 100)];
    [yPath appendPath:[UIBezierPath bezierPathWithOvalInRect:CGRectMake(80, 330, 100, 100)]];
    yPath.usesEvenOddFillRule = YES;
    [self addPath:yPath];
    
}

- (void)addPath:(UIBezierPath *)path{
    
    path.lineWidth = 4;
    [path stroke];
    [path fill];
}

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基本用法大致就这么多，本身也不是什么很难的东西，就介绍到这里吧