摘要：
初始化代码： if (!_alertView){_alertView = [[UIAlertView alloc] initWithTitle:title message:@"\n\n\n" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"登录", nil];_alertView.delegate = self;usernameField = [[UITextField alloc] initWithFrame:CGRectMake(12.0, 50.0, 260.0 阅读全文
