I am using a UINavigationController with a different Controller. I have overridden the BackButton from the Navigation. In some cases I want to jump to RootController if BackButton is tapped.
But in this case the user jumps Back, but the whole View is empty.
The behaviour is strange and I don’t know why. Can someone help me please.
To go to RootController I do the following.
if([self.tempnavigationInfo.refkey isEqual:#"main"]){
[self.navigationController popToRootViewControllerAnimated:NO];
}
For the BackButton I have implemented this handler:
#implementation UINavigationController (ShouldPopOnBackButton)
- (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item {
if([self.viewControllers count] < [navigationBar.items count]) {
return YES;
}
BOOL shouldPop = YES;
UIViewController* vc = [self topViewController];
if([vc respondsToSelector:#selector(navigationShouldPopOnBackButton)]) {
shouldPop = [vc navigationShouldPopOnBackButton];
}
if(shouldPop) {
dispatch_async(dispatch_get_main_queue(), ^{
[self popViewControllerAnimated:YES];
});
} else {
// Workaround for iOS7.1
for(UIView *subview in [navigationBar subviews]) {
if(subview.alpha < 1.) {
[UIView animateWithDuration:.25 animations:^{
subview.alpha = 1.;
}];
}
}
}
return NO;
}
In the ViewController I handle it this way:
-(BOOL) navigationShouldPopOnBackButton {
if (self.backConfirmation != nil
&& self.backConfirmation.navigation != nil
&& self.backConfirmation.confirmation == nil){
[[NSNotificationCenter defaultCenter] postNotificationName:#"gotoWithoutConfirmation" object:self.backConfirmation.navigation];
return NO;
}
return YES;
}
In my MainController I catch the notification and call the method with "popToRoot" logic above:
-(void) handleNotificationFromFormView:(NSNotification*) notification
{
if([notification.name isEqualToString:#"gotoWithoutConfirmation"]){
self.tempnavigationInfo = (NavigationInfo*)notification.object;
[self goBackTo];
}
in case anyone else ends up here - I had a similar issue that confused me for a while - it turned out to be because I was using a custom transition that moved the content of the root vc off screen. Popping to root without specifying a transition to reverse the translation means the root comes back with with its content off screen - it doesn't get reset to its default state automatically.
For example - if you set a custom transition using a UINavigationControllerDelegate like this:
class NavigationControllerDelegate: NSObject, UINavigationControllerDelegate {
func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationControllerOperation, from fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
if let _ = fromVC as? FirstVC, let _ = toVC as? SecondVC {
return SlideTransitionAnimator(direction: .left)
}
}
and your transition class does some transformation to the rootViewController - eg, as in my case, moving it off screen:
class SlideTransitionAnimator: NSObject, UIViewControllerAnimatedTransitioning {
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
guard let fromView = transitionContext.view(forKey: .from),
let toView = transitionContext.view(forKey: .to) else {return }
let containerView = transitionContext.containerView
containerView.addSubview(toView)
switch direction {
case .left:
toView.frame.origin.x = toView.frame.size.width
default:
toView.frame.origin.x = -toView.frame.size.width
}
UIView.animate(withDuration: 1,delay: 0, options: .curveEaseInOut,
animations: {
fromView.alpha = 0
switch self.direction {
case .left:
fromView.frame.origin.x -= fromView.frame.size.width
default:
fromView.frame.origin.x += fromView.frame.size.width
}
toView.alpha = 1.0
toView.frame.origin.x = 0
},
completion: { _ in
transitionContext.completeTransition(true)
})
}
}
if you don't reverse this animation or reset it when calling popToRootViewController you can end up with a seemingly empty root view controller.
Related
First off, this is my view controller/segue setup:
The three rightmost view controllers' background views are UIVisualEffectViews through which the source view controllers should be visible. They were added in the various viewDidLoad()s like this:
let blurEffect = UIBlurEffect(style: .dark)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = self.view.bounds
blurEffectView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
self.tableView.backgroundView = blurEffectView
Now, the main view controller (the "Garbage Day" one) is visible through the settings view controller, but the settings VC disappears whenever one of the two rightmost VCs is fully on screen. Here's a screen recording:
Screen recording of the source view controller dis- and reappearing
(Please ignore the glitches, the app I used to upload this apparently corrupted the video)
I get that technically, the Show segue doesn't have the "Over Current Context" thingy and therefore, I shouldn't expect the source VC to not disappear, but there has to be a way to make this work without custom segues.
I suggest you create a custom transition between view controllers.
I just wrote and tested this class:
class AnimationController: NSObject, UIViewControllerAnimatedTransitioning
{
var pushing = true
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.3
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let duration = transitionDuration(using: transitionContext)
let toVc = transitionContext.viewController(forKey: .to)!
let toView = transitionContext.view(forKey: .to)!
let fromView = transitionContext.view(forKey: .from)!
let container = transitionContext.containerView
if pushing {
container.addSubview(fromView)
container.addSubview(toView)
}
var finalFrame = transitionContext.finalFrame(for: toVc)
if pushing {
finalFrame.origin.x = finalFrame.width
toView.frame = finalFrame
finalFrame.origin.x = 0
} else {
finalFrame.origin.x = finalFrame.width
}
UIView.animate(withDuration: duration, delay: 0, options: .curveEaseOut, animations: {
if self.pushing {
toView.frame = finalFrame
} else {
fromView.frame = finalFrame
}
}) { (_) in
transitionContext.completeTransition(true)
if self.pushing {
container.insertSubview(fromView, belowSubview: toView)
} else {
fromView.removeFromSuperview()
}
}
}
}
In your UINavigationController class do the following:
class NavigationController: UINavigationController {
let animationController = AnimationController()
override func viewDidLoad() {
super.viewDidLoad()
delegate = self
}
}
And this extension:
extension NavigationController: UINavigationControllerDelegate
{
func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationControllerOperation, from fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
animationController.pushing = operation == .push
return animationController
}
}
However, this makes you lose the interactive dismiss gesture (Swiping from the left of the screen to dismiss) So you would need to fix that yourself.
So I've been following a couple tutorials on how to perform a custom animation when presenting a view controller. I currently have the following,
A class called TransitionManager which will be instantiated in ViewController A that will present the view
ViewController A that will present ViewController B in a navigation controller
According to all the tutorials i've read after setting the delegate in the presentation of the view, I should see my custom transition. However, the default animation is still used instead. I've tried moving the setting of the delegate before and after presenting with no avail
Transition Manager Class
class TransitionManager: NSObject, UIViewControllerAnimatedTransitioning, UIViewControllerTransitioningDelegate {
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
// get reference to our fromView, toView and the container view that we should perform the transition in
let container = transitionContext.containerView
let fromView = transitionContext.view(forKey: .from)!
let toView = transitionContext.view(forKey: .to)!
// set up from 2D transforms that we'll use in the animation
let offScreenRight = CGAffineTransform(translationX: container.frame.width, y: 0)
let offScreenLeft = CGAffineTransform(translationX: -container.frame.width, y: 0)
// start the toView to the right of the screen
if self.presenting {
toView.transform = offScreenRight
} else {
toView.transform = offScreenLeft
}
// add the both views to our view controller
container.addSubview(toView)
container.addSubview(fromView)
// get the duration of the animation
// DON'T just type '0.5s' -- the reason why won't make sense until the next post
// but for now it's important to just follow this approach
let duration = self.transitionDuration(using: transitionContext)
// perform the animation!
// for this example, just slid both fromView and toView to the left at the same time
// meaning fromView is pushed off the screen and toView slides into view
// we also use the block animation usingSpringWithDamping for a little bounce
UIView.animate(withDuration: duration, delay: 0.0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.8, options: [], animations: {
if self.presenting {
toView.transform = offScreenLeft
} else {
toView.transform = offScreenRight
}
toView.transform = .identity
}, completion: { finished in
// tell our transitionContext object that we've finished animating
transitionContext.completeTransition(true)
})
}
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.5
}
// MARK: UIViewControllerTransitioningDelegate protocol methods
// return the animataor when presenting a viewcontroller
func animationControllerForPresentedController(presented: UIViewController, presentingController presenting: UIViewController, sourceController source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
self.presenting = true
return self
}
// return the animator used when dismissing from a viewcontroller
func animationControllerForDismissedController(dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
self.presenting = false
return self
}
}
Class ViewController A
class ViewControllerA: UIViewController {
let transitionManager = TransitionManager()
func addButtonSelected() {
let vc = ViewControllerB()
let nav = UINavigationController(rootViewController: vc)
present(nav, animated: true, completion: nil)
nav.transitioningDelegate = self.transitionManager
}
}
Update your methods to swift3-:
func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return Transition()
}
func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return Transition()
}
You need to set the modalPresentationStyle to .custom, mentioned in the docs here and here. I'm not sure if it matters, but I've also always set the transitioning delegate before calling present:
nav.modalPresentationStyle = .custom
nav.transitioningDelegate = self.transitionManager
present(nav, animated: true, completion: nil)
I'm working with a few standard segues in storyboard and they each have the same background color. The issue I'm having is that when the segue transition nears completion there appears a dark shadow like background around the whole frame.
It's very faint, but enough to cause an issue. Has anyone come across this before?
The standard navigation controller push/pop animations darken the view that you're pushing from and the one you're popping to. If you don't like that, you can customize the transition, using an animation that just slides views in and out, but does no dimming of anything:
// this is the view controller you are pushing from
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
navigationController?.delegate = self
}
}
// make the view controller conform to `UINavigationControllerDelegate`
extension ViewController: UINavigationControllerDelegate {
func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationControllerOperation, from fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return PushPopAnimator(operation: operation)
}
}
// The animation controller
class PushPopAnimator: NSObject, UIViewControllerAnimatedTransitioning {
let operation: UINavigationControllerOperation
init(operation: UINavigationControllerOperation) {
self.operation = operation
super.init()
}
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.5
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let from = transitionContext.viewController(forKey: .from)!
let to = transitionContext.viewController(forKey: .to)!
let rightTransform = CGAffineTransform(translationX: transitionContext.containerView.bounds.size.width, y: 0)
if operation == .push {
to.view.transform = rightTransform
transitionContext.containerView.addSubview(to.view)
UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
to.view.transform = .identity
}, completion: { finished in
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
})
} else if operation == .pop {
to.view.transform = .identity
transitionContext.containerView.insertSubview(to.view, belowSubview: from.view)
UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
from.view.transform = rightTransform
}, completion: { finished in
from.view.transform = .identity
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
})
}
}
}
For information on custom transitions with view controllers, see WWDC 2013 video Custom Transitions Using View Controllers.
I have a custom Viewcontroller Transition for the Navigation Controller in my app. When the transition is performed, it hasn't resized the content of the child viewcontroller properly. The default transition does resize it.
I have added an example project on Github to demonstrate the issue.
The VC embedded in the Navigation Controller
import UIKit
class PopoverVCViewController: UIViewController, UIViewControllerTransitioningDelegate, UINavigationControllerDelegate {
let animator = Animator()
override func viewDidLoad() {
super.viewDidLoad()
navigationController?.delegate = self
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func navigationController(navigationController: UINavigationController, animationControllerForOperation operation: UINavigationControllerOperation, fromViewController fromVC: UIViewController, toViewController toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
animator.reverse = operation == .Pop
return animator
}
}
The animator
class Animator: NSObject, UIViewControllerAnimatedTransitioning {
var reverse: Bool = false
func animateTransition(transitionContext: UIViewControllerContextTransitioning) {
// get reference to our fromView, toView and the container view that we should perform the transition in
let container = transitionContext.containerView()!
let fromView = transitionContext.viewForKey(UITransitionContextFromViewKey)!
let toView = transitionContext.viewForKey(UITransitionContextToViewKey)!
// set up from 2D transforms that we'll use in the animation
let offScreenRight = CGAffineTransformMakeTranslation(container.frame.width, 0)
let offScreenLeft = CGAffineTransformMakeTranslation(-container.frame.width, 0)
// start the toView to the right of the screen
if (self.reverse == false) {
toView.transform = offScreenRight
}
else {
toView.transform = offScreenLeft
}
// add the both views to our view controller
container.addSubview(toView)
container.addSubview(fromView)
// get the duration of the animation
// DON'T just type '0.5s' -- the reason why won't make sense until the next post
// but for now it's important to just follow this approach
let duration = self.transitionDuration(transitionContext)
// perform the animation!
// for this example, just slid both fromView and toView to the left at the same time
// meaning fromView is pushed off the screen and toView slides into view
// we also use the block animation usingSpringWithDamping for a little bounce
UIView.animateWithDuration(duration, delay: 0.0, usingSpringWithDamping: 1.0, initialSpringVelocity: 0.0, options: UIViewAnimationOptions.CurveEaseInOut, animations: {
if (self.reverse == false) {
fromView.transform = offScreenLeft
}
else {
fromView.transform = offScreenRight
}
toView.transform = CGAffineTransformIdentity
}, completion: { finished in
// tell our transitionContext object that we've finished animating
transitionContext.completeTransition(true)
})
}
// return how many seconds the transiton animation will take
func transitionDuration(transitionContext: UIViewControllerContextTransitioning?) -> NSTimeInterval {
return 0.3
}
// MARK: UIViewControllerTransitioningDelegate protocol methods
// return the animataor when presenting a viewcontroller
// remmeber that an animator (or animation controller) is any object that aheres to the UIViewControllerAnimatedTransitioning protocol
func animationControllerForPresentedController(presented: UIViewController, presentingController presenting: UIViewController, sourceController source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return self
}
// return the animator used when dismissing from a viewcontroller
func animationControllerForDismissedController(dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return self
}
}
You can set the frame of toView to match the height and width of fromView :
let container = transitionContext.containerView()!
let fromView = transitionContext.viewForKey(UITransitionContextFromViewKey)!
let toView = transitionContext.viewForKey(UITransitionContextToViewKey)!
toView.frame = CGRectMake(toView.frame.origin.x, toView.frame.origin.y, fromView.frame.width, fromView.frame.height)
or like this:
UIViewController* toController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UIViewController* fromController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
and then setup this near the end of your animation routine:
toController.view.frame=fromController.view.frame;
I am trying something very simple but somehow I can't get it to work. All I try to do is switching between 2 View Controllers using an UISegmentedControl as you can see it for example in the App Store application in the Highlights tab.
I am using iOS5 and Storyboards.
Here's my Storyboad line up:
So I have a root View Controller and two UITableViews - This 2 TableViews I want to switch.
Here's how the implementation file looks like
#import "SegmentedLocationViewController.h"
#import "PastEventsLocationViewController.h"
#import "FutureEventsLocationViewController.h"
#interface SegmentedLocationViewController()
#property (weak, nonatomic) IBOutlet UISegmentedControl *segmentedControl;
#property (strong, nonatomic) NSArray *viewControllers;
#end
#implementation SegmentedLocationViewController
#synthesize segmentedControl = _segmentedControl;
#synthesize viewControllers = _viewControllers;
- (IBAction)indexDidChangeForSegmentedControl:(UISegmentedControl*)segmentedControl
{
NSLog(#"index: %d", segmentedControl.selectedSegmentIndex);
}
- (void)setupViewControllers
{
PastEventsLocationViewController *pastEventsLocationViewController = [[PastEventsLocationViewController alloc] initWithStyle:UITableViewStylePlain];
FutureEventsLocationViewController *futureEventsLocationViewController = [[FutureEventsLocationViewController alloc] initWithStyle:UITableViewStylePlain];
self.viewControllers = [NSArray arrayWithObjects:pastEventsLocationViewController, futureEventsLocationViewController, nil];
}
- (void)setupUI
{
[self.segmentedControl addTarget:self action:#selector(indexDidChangeForSegmentedControl:) forControlEvents:UIControlEventValueChanged];
}
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
[self setupViewControllers];
[self setupUI];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return YES;
}
#end
I can trigger the switch event and can log the currently selected index. But I don't have any idea where to go from here.
Maybe someone can turn my attention towards a certain direction...?
This code works pretty well for your purpose, I use it for one of my new apps.
It uses the new UIViewController containment APIs that allow UIViewControllers inside your own UIViewControllers without the hassles of manually forwarding stuff like viewDidAppear:
- (void)viewDidLoad {
[super viewDidLoad];
// add viewController so you can switch them later.
UIViewController *vc = [self viewControllerForSegmentIndex:self.typeSegmentedControl.selectedSegmentIndex];
[self addChildViewController:vc];
vc.view.frame = self.contentView.bounds;
[self.contentView addSubview:vc.view];
self.currentViewController = vc;
}
- (IBAction)segmentChanged:(UISegmentedControl *)sender {
UIViewController *vc = [self viewControllerForSegmentIndex:sender.selectedSegmentIndex];
[self addChildViewController:vc];
[self transitionFromViewController:self.currentViewController toViewController:vc duration:0.5 options:UIViewAnimationOptionTransitionFlipFromBottom animations:^{
[self.currentViewController.view removeFromSuperview];
vc.view.frame = self.contentView.bounds;
[self.contentView addSubview:vc.view];
} completion:^(BOOL finished) {
[vc didMoveToParentViewController:self];
[self.currentViewController removeFromParentViewController];
self.currentViewController = vc;
}];
self.navigationItem.title = vc.title;
}
- (UIViewController *)viewControllerForSegmentIndex:(NSInteger)index {
UIViewController *vc;
switch (index) {
case 0:
vc = [self.storyboard instantiateViewControllerWithIdentifier:#"FooViewController"];
break;
case 1:
vc = [self.storyboard instantiateViewControllerWithIdentifier:#"BarViewController"];
break;
}
return vc;
}
I got this stuff from chapter 22 of Ray Wenderlichs book iOS5 by tutorial.
Unfortunately I don't have a public link to a tutorial. But there is a WWDC 2011 video titled "Implementing UIViewController Containment"
EDIT
self.typeSegmentedControl is outlet for your UISegmentedControl
self.contentView is outlet for your container view
self.currentViewController is just a property that we're using to store our currently used UIViewController
It's Matthias Bauch solution, but thought of sharing it in Swift anyway!
Edit:
Adding a link to a Swift 2.0 ready made demo app.
https://github.com/ahmed-abdurrahman/taby-segmented-control
var currentViewController: UIViewController?
#IBOutlet weak var contentView: UIView!
#IBOutlet weak var segmentedControl: UISegmentedControl!
#IBAction func switchHappeningTabs(sender: UISegmentedControl) {
if let vc = viewControllerForSelectedSegmentIndex(sender.selectedSegmentIndex) {
self.addChildViewController(vc)
self.transitionFromViewController(self.currentViewController!, toViewController: vc, duration: 0.5, options: UIViewAnimationOptions.TransitionFlipFromRight, animations: {
self.currentViewController!.view.removeFromSuperview()
vc.view.frame = self.contentView.bounds
self.contentView.addSubview(vc.view)
}, completion: { finished in
vc.didMoveToParentViewController(self)
self.currentViewController!.removeFromParentViewController()
self.currentViewController = vc
}
)
}
}
override func viewDidLoad() {
super.viewDidLoad()
if let vc = self.viewControllerForSelectedSegmentIndex(self.segmentedControl.selectedSegmentIndex) {
self.addChildViewController(vc)
self.contentView.addSubview(vc.view)
self.currentViewController = vc
}
}
func viewControllerForSelectedSegmentIndex(index: Int) -> UIViewController? {
var vc: UIViewController?
switch index {
case 0:
vc = self.storyboard?.instantiateViewControllerWithIdentifier("FooViewController") as? UIViewController
case 1:
vc = self.storyboard?.instantiateViewControllerWithIdentifier("BarViewController") as? UIViewController
default:
return nil
}
return vc
}
For someone want to implement the same in swift
import UIKit
class HomeController: UIViewController {
var currentViewController:UIViewController?
#IBOutlet weak var homeController: UIView!
override func viewDidLoad() {
super.viewDidLoad()
let initialController:UIViewController = self.viewControllerForSegmentedIndex(0)
self.addChildViewController(initialController)
initialController.view.frame = self.homeController.bounds
self.homeController.addSubview(initialController.view)
self.currentViewController = initialController
}
#IBAction func segmentChanged(sender: UISegmentedControl) {
let viewCOntroller:UIViewController = viewControllerForSegmentedIndex(sender.selectedSegmentIndex)
self.addChildViewController(viewCOntroller)
self.transitionFromViewController(self.currentViewController!, toViewController: viewCOntroller, duration: 0.5, options: UIViewAnimationOptions.TransitionFlipFromBottom, animations: {
self.currentViewController?.view.removeFromSuperview()
viewCOntroller.view.frame = self.homeController.bounds
self.homeController.addSubview(viewCOntroller.view)
}, completion:{ finished in
viewCOntroller.didMoveToParentViewController(self)
self.currentViewController?.removeFromParentViewController()
self.currentViewController = viewCOntroller
})
}
func viewControllerForSegmentedIndex(index:Int) -> UIViewController {
var viewController:UIViewController?
switch index {
case 0:
viewController = self.storyboard?.instantiateViewControllerWithIdentifier("StoryboardIdForFirstController")
break
case 1:
viewController = self.storyboard?.instantiateViewControllerWithIdentifier("StoryboardIdForSecondController")
break
case 2:
viewController = self.storyboard?.instantiateViewControllerWithIdentifier("StoryboardIdForThirdController")
break
default:
break
}
return viewController!
}
}
Storyboard view
A is root view controller, and B, C is sub view controller.
When you click segment, add sub view controller.
result
design
code
import UIKit
class SegmentViewController: UIViewController {
#IBOutlet weak var containerView: UIView!
var leftViewController: LeftViewController!
var rightViewController: RightViewController!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
if let sb = storyboard {
leftViewController = sb.instantiateViewControllerWithIdentifier("leftViewController") as! LeftViewController
switchViewController(from: nil, to: leftViewController)
} else {
print("storyboard is nil")
}
}
func switchViewController(from fromVC: UIViewController?, to toVC: UIViewController?) {
if let from = fromVC {
from.willMoveToParentViewController(nil)
from.view.removeFromSuperview()
from.removeFromParentViewController()
} else {
print("fromVC is nil")
}
if let to = toVC {
self.addChildViewController(to)
to.view.frame = CGRectMake(0, 0, containerView.frame.width, containerView.frame.height)
self.containerView.insertSubview(to.view, atIndex: 0)
to.didMoveToParentViewController(self)
} else {
print("toVC is nil")
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
removeViewController()
}
func removeViewController() {
if let leftVC = leftViewController {
if let _ = leftVC.parentViewController {
print("leftVC is using")
} else {
print("set leftVC = nil")
leftViewController = nil
}
}
if let rightVC = rightViewController {
if let _ = rightVC.parentViewController {
print("rightVC is using")
} else {
print("set rightVC = nil")
rightViewController = nil
}
}
}
#IBAction func onSegmentValueChanged(sender: UISegmentedControl) {
UIView.beginAnimations("xxx", context: nil)
UIView.setAnimationDuration(0.4)
UIView.setAnimationCurve(.EaseInOut)
switch sender.selectedSegmentIndex {
case 0:
UIView.setAnimationTransition(.FlipFromRight, forView: self.containerView, cache: true)
if let leftVC = leftViewController {
switchViewController(from: rightViewController, to: leftVC)
} else {
if let sb = storyboard {
leftViewController = sb.instantiateViewControllerWithIdentifier("leftViewController") as! LeftViewController
switchViewController(from: rightViewController, to: leftViewController)
} else {
print("storyboard is nil")
}
}
default:
UIView.setAnimationTransition(.FlipFromLeft, forView: self.containerView, cache: true)
if let rightVC = rightViewController {
switchViewController(from: leftViewController, to: rightVC)
} else {
if let sb = storyboard {
rightViewController = sb.instantiateViewControllerWithIdentifier("rightViewController") as! RightViewController
switchViewController(from: leftViewController, to: rightViewController)
} else {
print("storyboard is nil")
}
}
}
UIView.commitAnimations()
}
}
You could embed your initial view controller in a navigation controller. Do that by selecting the view controller in the storyboard, then Editor->Embed in->Navigation Controller.
In your indexDidChangeForSegmentedControl: method you simply push the corresponding view controller to the navigation stack:
- (IBAction)indexDidChangeForSegmentedControl:(UISegmentedControl*)segmentedControl
{
[self.navigationController pushViewController:[self.viewControllers objectAtIndex:[segmentedControl.selectedIndex]] animated:YES];
}
But your approach makes not too much sense at all when you are using storyboards.
I don't know whether you can wire up a single segmented control button to a view controller using segues. Just try it.
I ended up using a navigation controller to achieve a similar functionality.
import UIKit
class BaseViewController: UIViewController {
var currentSegmentIndex = 0
#IBOutlet weak var segmentedControl: UISegmentedControl!
override func viewDidLoad() {
super.viewDidLoad()
segmentedControl.selectedSegmentIndex = currentSegmentIndex
}
#IBAction func segmentedControlChanged(_ sender: Any) {
let idx = segmentedControl.selectedSegmentIndex
let storyboard = UIStoryboard(name: "Main", bundle: nil)
switch idx {
case 0:
let vc = storyboard.instantiateViewController(
withIdentifier: "Foo") as! FooViewController
vc.currentSegmentIndex = 0
navigationController?.viewControllers = [vc]
break
case 1:
let vc = storyboard.instantiateViewController(
withIdentifier: "Bar") as! BarViewController
vc.currentSegmentIndex = 1
navigationController?.viewControllers = [vc]
break
default:
break
}
}
}