初识UI

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    UIWindow * window = [[UIWindowalloc]initWithFrame:[UIScreenmainScreen].bounds];

   self.window = window;

    window.backgroundColor = [UIColorgrayColor];

    [self.windowmakeKeyAndVisible];

   CGRect rect = self.window.frame;

    NSLog(@"%@",NSStringFromCGRect(rect));//获取当前window尺寸

    

    // 1. 创建一个视图并且显示到window

   UIView * view = [[UIViewalloc]init];

    view.frame =CGRectMake(200,100, 100, 190);// 控制当前视图的位置宽高

    view.backgroundColor = [UIColorgreenColor];//设置子控件的颜色

    

    [self.windowaddSubview:view];//添加子控件到父视图

    // 子视图frame

    NSLog(@"%@",NSStringFromCGRect(view.frame));

    // 子视图bounds

    NSLog(@"%@",NSStringFromCGRect(view.bounds));

    // 子视图中心

    NSLog(@"%@",NSStringFromCGPoint(view.center));

    

// 创建myView

   UIView * myView = [[UIViewalloc]init];

   CGRect  myRect = CGRectMake(120,220, 30, 40);

    myView.frame = myRect;

    myView.backgroundColor = [UIColorbrownColor];

    [self.windowaddSubview:myView];

// 创建mySecondView    

   UIView * mySecondView = [[UIViewalloc]initWithFrame:CGRectMake(100,200, 290, 40)];

    mySecondView.backgroundColor = [UIColorpurpleColor];

    [self.windowaddSubview:mySecondView];

    UIView，window，UIColor，CGRect，CGPoint，oc    

// 创建myThirdView

    //视图插入到当前的索引位置

   UIView * myThirdView = [[UIViewalloc]initWithFrame:CGRectMake(150,170, 90, 40)];

    myThirdView.backgroundColor = [UIColorcyanColor];

    UIView，window，UIColor，CGRect，CGPoint，oc    

    [self.windowinsertSubview:myThirdView atIndex:2];//将视图插入到下标的位置

    [self.windowinsertSubview:myView aboveSubview:myThirdView];// 将视图myView移到myThirdView之上

    [self.windowbringSubviewToFront:view];//将视图view移到最上面

UIView，window，UIColor，CGRect，CGPoint，oc    

    [self.windowsendSubviewToBack:myView];//将视图view移到最下面

    UIView，window，UIColor，CGRect，CGPoint，oc    

    [self.windowexchangeSubviewAtIndex:2withSubviewAtIndex:0];//将两位视图的下标交换，来交换两个视图的位置

    [view removeFromSuperview]; // 将子视图从父视图中删除掉

    UIView，window，UIColor，CGRect，CGPoint，oc    

UIView，window，UIColor，CGRect，CGPoint，oc    

    return YES;

}