代码创建button、view、label等控件

UIButton *b1=[[UIButton alloc]initWithFrame:CGRectMake(200, 200, 40, 20)];

b1.backgroundColor=[UIColor redColor];

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

view1.backgroundColor=[UIColor grayColor];

[self.view addSubview:view1];

[self.view addSubview:b1];

[b1 addTarget:self action:@selector(b1click:) forControlEvents:UIControlEventTouchUpInside];

UILabel *label=[[UILabel alloc]initWithFrame:CGRectMake(0, 0, 375, 17)];

label.backgroundColor=[UIColor yellowColor];

[self.view addSubview:label];