objective-c - 为什么 UIScrollView 在 xcode 7 中不起作用？

Question

我在 XCode 5 和 iOS 7 中创建了 UIScrollView 和 SubView。它工作正常，但我在 XCode 7 中运行并且它不滚动。我将 AutoLayouts 设置为 UIScrollview。我在 ViewDidLayoutSubviews 方法中编写了代码。

billViewScrolled2 是 CustomView (UIView)

-(void)viewdidload{

[super viewdidload];
    self.scrollViewTwo.translatesAutoresizingMaskIntoConstraints  = NO;
    self.billViewScrolled2.translatesAutoresizingMaskIntoConstraints = NO;
}

    -(void)viewDidLayoutSubviews
    {
        [self.scrollViewTwo setContentSize:CGSizeMake(self.billViewScrolled2.frame.size.width, 21 * [billDataArray count])];
        if (self.billViewScrolled2) {
            UIEdgeInsets scrollViewInsets = UIEdgeInsetsZero;

            scrollViewInsets.bottom = (CGRectGetHeight(self.scrollViewTwo.bounds) - CGRectGetHeight(self.billViewScrolled2.bounds)) / [billDataArray count]+ 160;

            self.scrollViewTwo.contentInset = scrollViewInsets;
        } else if (self.billViewScrolled2)
            self.scrollViewTwo.contentSize = CGSizeMake(CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds) + 1.0f);
    }

请帮我。