iOS：如何在当前UIViewcontroller中关闭其他UIViewcontroller

Question

I have three modal UIViewController "A","B" and "C". "A" and "C" is Portrait , "B" is "LandscapeRight" I click the button in "A" , "B" UIViewController will present , If I click the button in "B" , "C" UIViewController will present , When I click the button in "C" , I want to let "B" UIViewController dismiss before "C" UIViewController dismiss

I have try to put "B" UIViewController to "C" and dismiss the "B" when click the button

in "B"

let c = UIViewController()
c.b = self
self.presentViewController(c, animated: true, completion: nil)

then I click the button in "C"

b.dismissViewControllerAnimated(true, completion: { () -> Void in
    self.dismissViewControllerAnimated(true, completion: { () -> Void in

    })
})

When "C" is dismiss , "B" still display in the screen and did not disappear.

Answer 1

It is impossible to dismiss a view controller before the view controller present from it is disappeared. As an alternative,you can try this way,add a bool variable in the B,and change the variable in the C.

code in B:

var shouldShow:Bool = true

override func viewWillAppear(animated: Bool) {
    if !shouldShow{
        self.dismissViewControllerAnimated(false) { () -> Void in
            //
        }
    }
}

code in C:

@IBAction func clickButton(sender: AnyObject) {
    vc!.shouldShow = false
    self.dismissViewControllerAnimated(true, completion: { () -> Void in
        //
    })
}