UIViewSubviews多个views之间的关系

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

UIView *subView1 = [[UIView alloc] init];
    subView1.frame = CGRectMake(50, 50, 100, 100);
    [self.view addSubview:subView1];
    subView1.backgroundColor = [UIColor redColor];
    subView1.tag = 1;
    
    UIView *subView2 = [[UIView alloc] init];
    subView2.frame = CGRectMake(70, 70, 100, 100);
    subView2.backgroundColor = [UIColor orangeColor];
    [self.view addSubview:subView2];
    subView2.tag = 2;
    
    UIView *subView3 = [[UIView alloc] init];
    subView3.frame = CGRectMake(90, 90, 100, 100);
    subView3.backgroundColor = [UIColor yellowColor];
    [self.view addSubview:subView3];
    subView3.tag = 3;
    
    [self.view bringSubviewToFront:subView1];
    [self.view sendSubviewToBack:subView3];
    //[self.view exchangeSubviewAtIndex: 0 withSubviewAtIndex:2];

[self.view insertSubview:subView2 aboveSubview:subView3];
    [self.view insertSubview:subView3 belowSubview:subView1];

//subView2.hidden = YES;
    
    for(UIView *v in self.view.subviews)
    {
        NSLog(@"tag = %ld",v.tag);
    }

//[subView3 removeFromSuperview];
    for(UIView *v in self.view.subviews)
    {
        NSLog(@"%ld",v.tag);
    }
    
}
@end