ios - 为什么不会第二次调用 willDisplayCell

Question

我有一个带表格的 View Controller 。第一次创建和呈现单元格时，将按顺序调用以下函数(除了 View Controller 函数):

....
func viewWillAppear(_ animated: Bool)

func cellForRow(at indexPath: IndexPath) -> UITableViewCell? 

optional func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath)

func viewWillDisappear(_ animated: Bool)
.... 

当我退出屏幕时，调用了以下函数。

....
func viewWillAppear(_ animated: Bool)

func viewWillDisappear(_ animated: Bool)
.... 

但是为什么在viewWillAppear和viewWillDisappear之间没有调用willDisplaycell呢？

日志是:

viewWillAppear
cellForRowAtIndexPath: 0 
willDisplayCell: 0 
cellForRowAtIndexPath: 1 
willDisplayCell: 1 
cellForRowAtIndexPath: 2 
willDisplayCell: 2 
viewWillDisappear
viewWillAppear
viewWillDisappear

代替:

viewWillAppear
cellForRowAtIndexPath: 0 
willDisplayCell: 0 
cellForRowAtIndexPath: 1 
willDisplayCell: 1 
cellForRowAtIndexPath: 2 
willDisplayCell: 2 
viewWillDisappear
viewWillAppear
willDisplayCell: 0 
willDisplayCell: 1 
willDisplayCell: 2 
viewWillDisappear

Answer 1

我最终所做的是检查 viewDidAppear 中显示了哪些单元格。不确定这是最佳答案，所以请不要犹豫添加更好的答案。

-(void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];

    [self logVisibleSections];
}

-(void)logVisibleSections
{
    for (NSIndexPath *indexPath in self.tableView.indexPathsForVisibleRows)
    {
        // Do what needs to be done with visible cells 
    }
}