NOTE

 LABEL自动换行
  label.lineBreakMode = UILineBreakModeWordWrap;
     label.numberOfLines = 0;

结合ScrollView后关于UIPageControl的页面设置算法：

// 在ScrollView的委托方法中

int index = fabs(scrollView.contentOffset.x) / scrollView.frame.size.width;
pageControl.currentPage = index;

也可以：

    // Switch the indicator when more than 50% of the previous/next page is visible
    CGFloat pageWidth = scrollView.frame.size.width;
    int page = floor((scrollView.contentOffset.x - pageWidth / 2) / pageWidth) + 1;
    mypageControl.currentPage = page;