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iosswiftxcodeuiscrollview

Trigger action from view within scrollview

I am making an app where the user can switch between views using scrollview, it is like paging with scroll view. I instantiate 3 viewcontrollers and then put them side by side in the scroll view. The layout and everything are working, the only problem I have, that for some reason I cannot get any button or control to trigger any action/function in the third Viewcontroller.

The first one is just a placeholder, but everything in the second view works, but the third just does not trigger anything. Here is a picture so you can see the setup:

storyboard

My question is, what can I do so that the segmented control can trigger actions in the third view?

Thanks for your help in advance.

EDIT: Here is some code if it helps!

var appllicationPages: [UIView] {
    get {
        let firstPage = storyboard!.instantiateViewController(withIdentifier: OnboardPageNames.firstPage).view!
        let secondPage = storyboard!.instantiateViewController(withIdentifier: OnboardPageNames.secondPage).view!
        let thirdPage = storyboard!.instantiateViewController(withIdentifier: OnboardPageNames.thirdPage).view!
        
        return [firstPage,secondPage,thirdPage]
    }
}

func setupScrollView(from pages: [UIView])
{
    scrollView.delegate = self
    scrollView.isPagingEnabled = true
    
    scrollView.frame = CGRect(x: 0, y: 0, width: view.frame.width, height: view.frame.height)
    scrollView.contentSize = CGSize(width: view.frame.width * CGFloat(pages.count), height: view.frame.height)
    
    for i in 0 ..< pages.count {
        pages[i].frame = CGRect(x: view.frame.width * CGFloat(i), y: 0, width: view.frame.width, height: view.frame.height)
        scrollView.addSubview(pages[i])
    }
}

And then the function in VC three which is not executing (i hooked the segmented control up with Storyboard)

@IBAction func typeSwitched(_ sender: Any) {
    print("Hello There")
}
Solution

  • Thanks to the answers of DonMag and Amais Sheikh i managed to solve the problem!

    As described in the comments, the problem was, that i only loaded the views, and not the controllers.

    So i just had to add two lines of code:

    func setupScrollView(from pages: [UIViewController])
{
    scrollView.delegate = self
    scrollView.isPagingEnabled = true
    
    scrollView.frame = CGRect(x: 0, y: 0, width: view.frame.width, height: view.frame.height)
    scrollView.contentSize = CGSize(width: view.frame.width * CGFloat(pages.count), height: view.frame.height)
    
    for i in 0 ..< pages.count {
        pages[i].view.frame = CGRect(x: view.frame.width * CGFloat(i), y: 0, width: view.frame.width, height: view.frame.height)
        scrollView.addSubview(pages[i].view)
        let VC = pages[i]
        
        // These lines helped me solve the problem
        self.addChild(VC)
        VC.didMove(toParent: self)
    }
}

    And i changed the array to ViewController instead of Views:

    var appllicationPages: [UIViewController] {
    get {
        let firstPage = storyboard!.instantiateViewController(withIdentifier: MainAppPages.firstPage)
        let secondPage = storyboard!.instantiateViewController(withIdentifier: MainAppPages.secondPage)
        let thirdPage = storyboard!.instantiateViewController(withIdentifier: MainAppPages.thirdPage)
        
        return [firstPage,secondPage,thirdPage]
    }
}