一个可缩放的刻度尺

需求：可缩放，二级刻度可显隐。

 

两个思路：1.所有的刻度都画出来，根据缩放比例控制二级刻度的显隐。理论上会流畅些。

　　　　　2.开始只展示一级刻度，当缩放比例超过某个级别时候，添加子刻度。

 

尝试第二条，主要代码：

 

-(void)layoutSubviews
{
    [super layoutSubviews];
    
    for (UIView *view in self.subviews) {
        if (1024 == view.tag) {
            [view removeFromSuperview];
        }
    }
    
    for (NSInteger i = 0; i < _count; i++) {
        UIView *sign = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 6, 6)];
        sign.tag = 1024;
        sign.backgroundColor = [UIColor redColor];
        CGPoint center = CGPointMake(i * self.frame.size.width / _count, self.frame.size.height / 2);
        sign.center = center;
//        sign.layer.cornerRadius = 3;
//        sign.clipsToBounds = YES;
        [self addSubview:sign];
        
        if (self.width > _originLength * 10) {
            if (i < _count) {
                for (NSInteger j = 0; j < 10; j++) {
                    UIView *sign = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 4, 4)];
                    sign.tag = 1024;
                    sign.backgroundColor = [UIColor redColor];
                    CGPoint center = CGPointMake(i * self.frame.size.width / _count + j * self.frame.size.width / _count / 10, self.frame.size.height / 2);
                    sign.center = center;
                    sign.layer.cornerRadius = 2;
                    sign.clipsToBounds = YES;
                    [self addSubview:sign];
                }
            }
        }
    }
}