Switch child viewcontrollers programmatically : XLPagerTabStrip

Question

I have been using the XLPagerTabStrip to effectively create a tab bar at the top of my view controller, with multiple child view controllers displayed within it. Lets call Home as parent controller which extends ButtonBarPagerTabStripViewController. There are two child view controller, Child1 and Child2. Everything working perfect as I expected. But now I need a requirement, in which I have to switch child view controllers programmatically. ie, when a process(in child2) finished, it should trigger the switching the tab from Child 2 to Child1. I know there are couple of methods,

func moveToViewController(at index: Int)
func moveToViewController(at index: Int, animated: Bool)
func moveTo(viewController: UIViewController)
func moveTo(viewController: UIViewController, animated: Bool)

but I don't know how to use it.

can you further explain the question because what you are trying to do is pretty straight forward. Where are you stuck? — Adeel Miraj, Nov 21 '16 at 19:32
@Adeel I just need to switch the tabs from another. ie, I want to go back to child 1 from child 2 after finishing an API call. Given methods are used in XLPagerTabstrip. But I don't know how to use it? — ASP, Nov 22 '16 at 17:59

score 8 · Answer 1 · answered Dec 21 '16 at 18:10

The method is pretty straight forward, but you need to call it in your Home(parent View Controller)

In your Child2 view controller class, write the code as below

//after some process done here

let parentViewController = self.parent! as ParentViewController

parentViewController.moveToViewController(at: 0) //Assume your child1 view controller is on index 0

score 1 · Answer 2 · answered Sep 10 '17 at 14:42

**These methods can be used as following:

Will show how to use these functions through delegate

func moveToViewController(at index: Int) :

You need to pass the index of the target child controller, for this you can either call this func from your child controller by initialising the parent controller or you can set a delegate which will be implemented in your parent controller and should be triggered from your child view controller, ultimately it will select the target controller with animation.

 protocol MyDelegate {
   func selectChildControllerAtIndex(toIndex: Int!)
   func selectViewController(viewController: UIViewController)
 }

ChildProcceedPressedDelegate needs to be conformed in your parent controller

In selectViewController you need to pass the reference of your target controller from your child controller, which you can do by storing it somewhere and passing it.

internal func selectViewController(viewController: UIViewController) {
    moveTo(viewController: viewController, animated: true)
}

In selectChildControllerAtIndex you just need to pass the index of your target controller:

func selectChildControllerAtIndex( toIndex: Int!) {
    self.moveToViewController(at: index, animated: true)
}

func moveToViewController(at index: Int, animated: Bool) :

It works same as above method but in this you can pass if you want to animate to your target controller or not. Use delegate: selectChildControllerAtIndex

func moveTo(viewController: UIViewController)

It works by passing your target child controller reference and it will animate to your target controller. by delegate: selectViewController

func moveTo(viewController: UIViewController, animated: Bool)

It works by passing your target child controller reference and it will animate as per your choice to your target controller. by delegate: selectViewController

score 1 · Answer 3 · answered May 23 '21 at 05:20

Here is the perfect solution to move any specific childview controller. You just need some delay to change viewcontroller

DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
     self.moveToViewController(at: 1, animated: true)
  }

call this lines of code inside viewDidLoad() method.

Switch child viewcontrollers programmatically : XLPagerTabStrip

3 Answers3