警告:尝试在已经呈现的MainTableViewController上呈现ModalTableViewController(空) [英] Warning: Attempt to present ModalTableViewController on MainTableViewController which is already presenting (null)

问题描述

我的弹出式窗口有问题.如果我点击一个单元格，我将加载一个弹出窗口以选择更多详细信息.一切正常，但是当我再次按一下单元格时，每次都会收到以下消息:

I have a problem with a popover. If I tap on a cell I will load a popover to select more details. Everything works fine, but when I press my cell again I receive every time the following message:

警告:尝试在MainTableViewController上呈现ModalTableViewController ...，该组件已经呈现(null)

Warning: Attempt to present ModalTableViewController... on MainTableViewController... which is already presenting (null)

如果我点击另一个单元格，则不会收到此警告.仅当再次点击同一行时.

If I tap on another cell I will not get this Warning. Only if a tap the same row again.

我尝试了很多事情，但无法解决此问题.我这样加载弹出窗口:

I tried lots of things but I am not able to solve this problem. I load my popover with like this:

var popover: UIPopoverController!
var popoverContent: ModalTableViewController!

然后在我的手机上点击:

and on my cell tap:

popoverContent = self.storyboard.instantiateViewControllerWithIdentifier("ModalTableViewController") as ModalTableViewController

popoverContent.selectedQuestionID = indexPath!.row               
popover = UIPopoverController(contentViewController: popoverContent)
popover.delegate = self

popover.presentPopoverFromRect(currentCell.LabelCellTitle.frame, inView: currentCell.LabelCellTitle.superview, permittedArrowDirections: UIPopoverArrowDirection.Left, animated: true)

并解雇

func popoverControllerDidDismissPopover(popoverController: UIPopoverController!) {

    popover.dismissPopoverAnimated(false) // just to check

    self.popover = nil
    self.popoverContent = nil

}

有什么想法吗?

如果我检查以下内容:

if(self.popoverContent == nil) {

在打开它之前，我会发现当我再次点击同一单元格时它不是零.

before opening it, I'll find out that it's not nil when I tap the same cell again.

再次

如果我使用稍微不同的设置来创建它，则会遇到相同的问题:

I have the same problem if I create it with a little different setup:

自定义1x1px按钮.将popover与segue连接.在单元格上，点击将按钮移至单元格并打开弹出窗口.

Custom 1x1px Button. Connect popover with segue. On cell tap move button to cell and open popover.

因此，仅使用情节提要编辑器，没有用于打开弹出窗口的代码.

So there is no code for opening the popover, only with storyboard editor.

有时，即使我再次点击相同的弹出框，也会收到相同的错误消息.

I get the same error message (sometimes) just if I tap the same popover again.

推荐答案

我还不快，但是对于Objective-C，我最终将presentViewController调用包装在performSelector调用中.

I'm not on swift yet, but for Objective-C, I ended up wrapping the presentViewController call in a performSelector call.

-(void) present
{
    [self performSelector: @selector(ShowModalTableViewController) withObject: nil afterDelay: 0];
}

-(void) ShowModalTableViewController
{
    [self presentViewController: ctrlModalTableViewController animated: true completion: nil];
}

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