iOS 画虚线

- (void)viewDidLoad {
    [super viewDidLoad];

    UIView * view = [[UIView alloc]init];
    [self.view addSubview:view];
    _view = view;
    [view mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.offset = 100;
        make.width.offset =100;
        make.centerX.offset = 0;
        make.height.offset = 2;
    }];
    [self.view layoutIfNeeded];
    [self drawDashLine:view lineLength:10 lineSpacing:5 lineColor:UIColor.redColor];
    
}
//画虚线
- (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];
    //  设置虚线颜色为blackColor
    [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]];
//    shapeLayer setLineDashPattern:<#(NSArray * _Nullable)#>
    //  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];
    
}

效果图

Simulator Screen Shot - iPhone 13 - 2021-12-01 at 09.27.47.png