iOS oc-调整view层级

- (void)viewDidLoad {

[super viewDidLoad];

// Do any additional setup after loading the view, typically from a nib.

UIView *view1 = [[UIView alloc] initWithFrame:CGRectMake(10, 50, 100, 50)];

view1.backgroundColor = [UIColor blueColor];

[self.view addSubview:view1];

UIView *view2 = [[UIView alloc] initWithFrame:CGRectMake(15, 55, 100, 50)];

view2.backgroundColor = [UIColor grayColor];

[self.view addSubview:view2];

//如果将下面两行代码都注释掉  view1 会在下面  view2会在上面

//  下面这行代码能够将view2  调整到父视图的最下面

//    [self.view sendSubviewToBack:view2];

//将view调整到父视图的最上面

[self.view bringSubviewToFront:view1];

//插入层级

//- (void)insertSubview:(UIView *)view atIndex:(NSInteger)index;

}