//MainViewController
override func prepareForSegue(segue: UIStoryboardSegue,sender: AnyObject?)
{

    if segue.identifier == "GoToSecondViewControllerSegue"
    {
        var vc = segue.destinationViewController as! SecondViewController
        var controller = vc.popoverPresentationController

        if controller != nil
        {
            controller?.delegate = self
            vc.inputTextDelegate = "I'm a popover!"
        }
    }
}

func popoverPresentationControllerDidDismissPopover(popoverPresentationController: UIPopoverPresentationController) {
     println("done")
}

func adaptivePresentationStyleForPresentationController(controller: UIPresentationController) -> UIModalPresentationStyle
{
    return .None
}

//SecondViewController
@IBAction func dismissPopover(sender: UIButton) {
     dismissViewControllerAnimated(true,completion: nil)
     //This dismisses the popover but does not notify the MainViewConroller
}

segue的锚点连接到一个按钮：

现在我有两个问题：

>当我点击popover内的取消按钮时,它会解除弹出窗口但不会在MainViewController中触发popoverPresentationControllerDidDismissPopover
>我如何将数据从SecondViewController传递到MainViewController,例如UITextView的文本值.