UIVIew画虚线

- (void)drawLine{
    CAShapeLayer *shapeLayer = [CAShapeLayer layer];
    
    [shapeLayer setBounds:self.bounds];
    [shapeLayer setPosition:self.center];
    [shapeLayer setFillColor:[[UIColor clearColor] CGColor]];
    // 设置虚线颜色为blackColor [shapeLayer setStrokeColor:[[UIColor blackColor] CGColor]];
    [shapeLayer setStrokeColor:[[UIColor colorWithRed:223/255.0 green:223/255.0 blue:223/255.0 alpha:1.0f] CGColor]];
    // 3.0f设置虚线的宽度
    [shapeLayer setLineWidth:1.0f];
    [shapeLayer setLineJoin:kCALineJoinRound];
    // 3=线的宽度 1=每条线的间距
    [shapeLayer setLineDashPattern:[NSArray arrayWithObjects:[NSNumber numberWithInt:1],[NSNumber numberWithInt:1],nil]];
    // Setup the path
    CGMutablePathRef path = CGPathCreateMutable();
    // 0,10代表初始坐标的x，y
    // 320,10代表初始坐标的x，y
    CGPathMoveToPoint(path, NULL, 0, 0);
    CGPathAddLineToPoint(path, NULL, 0,63);
    
    [shapeLayer setPath:path]; 
    CGPathRelease(path);
    [_verticalLine.layer addSublayer:shapeLayer];
}

#import <UIKit/UIKit.h>

@interface LineDashView : UIView

@property (nonatomic, strong) NSArray   *lineDashPattern;  // 线段分割模式
@property (nonatomic, assign) CGFloat    endOffset;        // 取值在 0.001 --> 0.499 之间

- (instancetype)initWithFrame:(CGRect)frame lineDashPattern:(NSArray *)lineDashPattern endOffset:(CGFloat)endOffset;

@end

#import "LineDashView.h"

@interface LineDashView ()

{
    CAShapeLayer  *_shapeLayer;
}

@end

@implementation LineDashView

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self)
    {
        UIBezierPath *path      = [UIBezierPath bezierPathWithRect:self.bounds];
        _shapeLayer             = (CAShapeLayer *)self.layer;
        _shapeLayer.fillColor   = [UIColor clearColor].CGColor;
        _shapeLayer.strokeStart = 0.001;
        _shapeLayer.strokeEnd   = 0.499;
        _shapeLayer.lineWidth   = frame.size.width;
        _shapeLayer.path        = path.CGPath;
    }
    return self;
}

- (instancetype)initWithFrame:(CGRect)frame
              lineDashPattern:(NSArray *)lineDashPattern
                    endOffset:(CGFloat)endOffset
{
    LineDashView *lineDashView   = [[LineDashView alloc] initWithFrame:frame];
    lineDashView.lineDashPattern = lineDashPattern;
    lineDashView.endOffset       = endOffset;
    
    return lineDashView;
}

#pragma mark - 修改view的backedLayer为CAShapeLayer
+ (Class)layerClass
{
    return [CAShapeLayer class];
}

#pragma mark - 改写属性的getter,setter方法
@synthesize lineDashPattern = _lineDashPattern;
- (void)setLineDashPattern:(NSArray *)lineDashPattern
{
    _lineDashPattern            = lineDashPattern;
    _shapeLayer.lineDashPattern = lineDashPattern;
}
- (NSArray *)lineDashPattern
{
    return _lineDashPattern;
}

@synthesize endOffset = _endOffset;
- (void)setEndOffset:(CGFloat)endOffset
{
    _endOffset = endOffset;
    if (endOffset < 0.499 && endOffset > 0.001)
    {
        _shapeLayer.strokeEnd = _endOffset;
    }
}
- (CGFloat)endOffset
{
    return _endOffset;
}

#pragma mark - 重写了系统的backgroundColor属性
- (void)setBackgroundColor:(UIColor *)backgroundColor
{
    _shapeLayer.strokeColor = backgroundColor.CGColor;
}
- (UIColor *)backgroundColor
{
    return [UIColor colorWithCGColor:_shapeLayer.strokeColor];
}

@end

LineDashView *line1 = [[LineDashView alloc] initWithFrame:CGRectMake(verticalLineX, verticalLineY, 1, 63) lineDashPattern:@[@1, @1] endOffset:0.495];
    line1.backgroundColor = [UIColor redColor];
    [self.contentView addSubview:line1];