gist for http://www.v2ex.com/t/89274#reply7

WeChatView.m

@implementation WeChatView

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        UIImageView *logoImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"logo.png"]];
        logoImageView.frame = CGRectMake(.0f, .0f, 50.0f, 50.0f);
        self.backgroundColor = [UIColor grayColor];
        [self addSubview:logoImageView];
        
        _containerView = [[UIScrollView alloc] initWithFrame:frame];
        _containerView.backgroundColor = [UIColor clearColor];
        _containerView.bounces = YES;
        _containerView.alwaysBounceVertical = YES;
        [self addSubview:_containerView];
        
        _messageView = [[UIView alloc] initWithFrame:frame];
        _messageView.backgroundColor = [UIColor whiteColor];
        [_containerView addSubview:_messageView];
    }
    return self;
}


@end