iOS中的UIView的基本属性1

@interface AppDelegate ()

@end

@implementation AppDelegate


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    //UIweindow 应用程序的窗口,用于将内容展示给用户
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    //创建view
    UIView *redView = [[UIView alloc] initWithFrame:CGRectMake(50, 90, 100, 100)];
    //设置背景颜色
    redView.backgroundColor=[UIColor redColor];
    
    //添加到父控件
    [self.window addSubview:redView];

    
    //一个视图只有一个父视图
    UIView *grayView = [[UIView alloc] initWithFrame:CGRectMake(50,200, 100,100)];
    
    UIView *greenView = [[UIView alloc] initWithFrame:CGRectMake(56,200, 100,100)];
    [self.window addSubview:greenView];
    
    
    greenView.backgroundColor = [UIColor greenColor];
    grayView.backgroundColor = [UIColor grayColor];
  
    
    [redView addSubview:grayView];
    [self.window addSubview:grayView];

    //释放内存
    [redView release];
    [grayView release];
    [greenView release];
    
    
    
    
    //UIView的重要属性
    //1.backgroundColor 背景颜色
    //2.hidden 显隐性 //控制视图的显隐性,默认为NO
    //3.alpha 透明度,控制视图的透明度,取值范围0.0 - 1.0
    //4.superview 获得父视图
    //5.subvievs 获得子视图,使用数组进行管理,子视图的添加是有序的,添加顺序对应上数组元素的位置
    //6.tag 标签,唯一标示指定视图
    [self.window viewWithTag:250];
    
    //通过字视图也可以获得 子
    //UIView *lase = [self.window subviews].lastObject;
    
    
        
    
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];

    //设置Window的背景颜色
    //让UIwindow成为程序的主窗口,并且可视
    //[self.window makeKeyAndVisible];
  
    return YES;
}