self.view.backgroundColor = [UIColor whiteColor];
UILabel *mylabel = [[UILabel alloc] init];
mylabel.backgroundColor = [UIColor blackColor];
mylabel.frame = CGRectMake(0, 0, 100, 100);
[mylabel layoutIfNeeded]; //需要在设置完frame后调用下这个方法 或者 text不为中文也可以
mylabel.text = @"我们";
mylabel.clipsToBounds = NO;
[self.view addSubview:mylabel];
UIView *mymy = [[UIView alloc] init];
mymy.backgroundColor = [UIColor blueColor];
mymy.frame = CGRectMake(0, 0, 300, 30);
[mylabel addSubview:mymy];