方法封装：
- (void)drawDashLine:(UIView *)lineView lineLength:(int)lineLength lineSpacing:(int)lineSpacing lineColor:(UIColor *)lineColor{
CAShapeLayer *shapeLayer = [CAShapeLayer layer];
[shapeLayer setBounds:lineView.bounds];
[shapeLayer setPosition:CGPointMake(CGRectGetWidth(lineView.frame) / 2, CGRectGetHeight(lineView.frame))];
[shapeLayer setFillColor:[UIColor clearColor].CGColor];
// 设置虚线颜色
[shapeLayer setStrokeColor:lineColor.CGColor];
// 设置虚线宽度
[shapeLayer setLineWidth:CGRectGetHeight(lineView.frame)];
[shapeLayer setLineJoin:kCALineJoinRound];
// 设置线宽，线间距
[shapeLayer setLineDashPattern:[NSArray arrayWithObjects:[NSNumber numberWithInt:lineLength],[NSNumber numberWithInt:lineSpacing], nil]];
// 设置路径
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, 0, 0);
CGPathAddLineToPoint(path, NULL,CGRectGetWidth(lineView.frame), 0);
[shapeLayer setPath:path];
CGPathRelease(path);
// 把绘制好的虚线添加上来
[lineView.layer addSublayer:shapeLayer];
}
调取使用：
[self drawDashLine:self.lineView lineLength:10 lineSpacing:5 lineColor:kColorHex(0xEDEDED)];
1.参数self.lineView：虚线所在view；
2.参数lineLength：虚线中实线的长度；
3.参数lineSpacing：虚线中每个实现的间距；
