iOS 視圖層次管理 sendSubviewToBack、bringSubviewToFront

直接上代碼

- (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];
    
    //如果將下面兩行代碼都註釋掉   view1 會在下面   view2會在上面
    //  下面這行代碼能夠將view2  調整到父視圖的最下面
//    [self.view sendSubviewToBack:view2];
    //將view調整到父視圖的最上面
    [self.view bringSubviewToFront:view1];
    
}