Back Button with Multiple Sources - ios

Within my app, I want to create a user profile controller, which can be navigated to from several different controllers. I would like it to have a back button that will take the user back to whichever controller they came from.
How do I do this?

Dismiss
Add UIButton for back navigation somewhere to your UserProfileController. Then in UserProfileController create action and set it as action of your button. This action dismisses your UserProfileController (so you get back to previous UIViewController)
#IBAction func backButtonPressed(_ sender: UIButton) {
dismiss(animated: true, completion: nil)
}
UINavigationController
Alternatively you can have previous ViewControllers embed in UINavigationController. Then you will be able to tap to back button (which is set by default) in UINavigationBar which gets you to previous UIViewController

Related

How to show the tab bar when using Segue back in swift

I have a Tab bar in the first view and a total of two views.
However, when I move from the first view to the second view and then back to the first view using the Segue, the Tab bar of the first view disappears.
When return to the first view from the second view, what is the way the Tab bar does not disappear?(without using unwind)
Don't use unwind segue here. When you need to get back to previous ViewController, just dismiss your current ViewController
dismiss(animated: true, completion: nil) /* call this in second VC */
I suggest you read the documentation for understanding how combined View Controller Interfaces. Anyway, if you need to pop to previous view controller on the flow, you need to use
navController.popViewController(animated: true)
But, if the need to pop up on the specific ViewController on the queue of View Controllers in the NavigationViewController, you need to use
navController.popToViewController(ViewController, animated: true)
From the moment you are using a NavigationController, a return button will automatically appear on the UINavigationBar, so you do not have to worry about that. Unless you want to customize the back buttons in the viewcontrollers queue, in this case use the above methods.
It's for page 1. Display tabBarController once page is loaded.
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
self.tabBarController?.tabBar.hidden = true
}
If click event is fired, hide tabBarController.
override func prepareForSegue(segue: UIStoryboardSegue!, sender: AnyObject!) {
if (segue.identifier == "twoSegue") {
self.tabBarController?.tabBar.hidden = false
}
}

how can i deallocate viewControllers in ios

I made some views ordering like Login -> Navigation Controller[Dashboard -> Detail]
In LoginViewController, There is Login Button and it has Action
#IBAction func loginTapped(_ sender: Any){
let mainNavigationController = storyboard?.instantiateViewController(withIdentifier: "MainNavigationViewController") as! MainNavigationViewController
present(mainNavigationController, animated: true, completion: nil)
}
In NagivationController
There are two Views,Dashboard and Detail
Detail View is pushed by segue action from Dashboard
and Dashboard has tab bar Item to logout
I know that when back button is tapped in Detail view, It doesn't deallocating Detail View. It just push back to Navigation Controller's Stack (Is it right...?)
but when i tapped Logout Button in Dashboard, I thought Navigation Controller which contains two views (Dashboard, Detail) should be deallocated
but it doesn't deallocated.
I set the deinit method in Navigation View Controller like this
deinit {
print("Main Navigation View Controller is deinited")
}
but it never called
How can i deallocate views that appear after login, when i tapped logout button
Sorry for poor syntax in English because i'm not Native

dismiss two controllers Swift

I have this situation :
I have a first view controller , when tap on button in it I open in modal mode another view controller , in this view controller when I tap another button I open in modal view another view controller and in it there is a button and when I tap on it I want to go to first view controller without re-initialize it.
How do I do it?
This is the perfect situation for an unwind segue.
Put this in your first viewController (the one you want to return to):
#IBAction func backFromVC3(_ segue: UIStoryboardSegue) {
print("We are back in VC1!")
}
Then in the Storyboard in your 3rd viewController, control-drag from your button to the exit icon at the top of the viewController and choose backFromVC3 from the pop-up.
Now, when the user presses the button in VC3, both VC3 and VC2 will be dismissed and you will return to VC1.
If you are not using Storyboards, you can dismiss the viewControllers with code. Here is code for a button's handler to dismiss two levels of viewController:
func doDismiss(_ sender: UIButton) {
// Use presentingViewController twice to go back two levels and call
// dismissViewController to dismiss both viewControllers.
self.presentingViewController?.presentingViewController?.dismiss(animated: true, completion: nil)
}
Thanks all for reply and edited my question :)
I found 2 line code to resolved my problem:
let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
appDelegate.window!.rootViewController?.dismissViewControllerAnimated(true, completion: nil).
And that work well.
Thanks very much

Go back to previous view controller doesn't work

My first view controller has a button, which triggers the #IBAction goTo2ndVc() which presents a second ViewController:
class FirstVC: UIViewController {
...
#IBAction func goTo2ndVc() {
let secondVc = SecondVC(label: "I am second vc.")
self.presentViewController(secondVc, animated: true, completion: nil)
}
When the button is pressed, the 2nd view controller is shown on screen. No problem.
In 2nd view controller, there is also a button which is used to go back to 1st view controller:
class SecondVC: UIViewController {
...
#IBAction func backToFirst(sender: AnyObject) {
print("go back ...")
self.navigationController?.popViewControllerAnimated(true)
}
}
I looked on internet, people suggest to use navigationController?.popViewControllerAnimated(true) to go back to previous controller. But when I press the go back button I can see the print message "go back ..." but the app doesn't go back to 1st view controller. WHY?
#IBAction func backToFirst(sender: AnyObject) {
print("go back ...")
self.dismissViewControllerAnimated(true, completion: nil)
}
In Swift 3
self.dismiss(animated: true, completion: nil)
you should not use navigation controller, because you didn't use it when you were adding the second view controller. that's why simply call dismissViewControllerAnimated method.
You have to use UINavigationController and its pop methods only when you add your view controllers via pushViewController method.
Familiarize yourself with the concept of navigation controller here: https://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/ViewControllerCatalog/Chapters/NavigationControllers.html
there
the issue is very simple..
self.presentViewController(secondVc, animated: true, completion: nil)
the code will present second view, you are not pushing it.
self.navigationController?.popViewControllerAnimated(true)
the popViewController will pop back to the previous view controller from where it is been pushed.
So, there are two ways you can achieve what you want
1)If you want to present viewController then you have to dismiss the view controller to show previous view controller with
self.dismissViewControllerAnimated(true, completion: nil)
2)If you want to use PopToVewcontroller, then you have to push you second view controller instead of presenting it with
self.navigatioVonroller?.pushViewController(secondVc, animated: true)
If you want to return to the previous view controller, you can simply add:
[self dismissViewControllerAnimated:YES completion:nil];
to the button action method.
If this is added on the nav view controller present on every screen, I see no reason why it shouldn't work as it would always dismiss the most recently presented view.

Swift: miss tab bar after click Back button

I'm new to swift and IOS development. I'm working on a tabbed application(3 views). For example, FirstView, SecondView and ThirdView. FirstView has a button that opens a addNewSession view and the addNewSession view has a Back button that back to the FirstView. The problem is Tab bar disappears after back from the addNewSession view
FirstView to addNewSession view.
#IBAction func toAddNew(sender: AnyObject) {
let addNewSession = self.storyboard?.instantiateViewControllerWithIdentifier("addNewSession") as addNew
self.presentViewController(addNewSession, animated: true, completion: nil)
}
addNewSession view to FirstView
#IBAction func backToPrev(sender: AnyObject) {
println("test1")
let FirstView = self.storyboard?.instantiateViewControllerWithIdentifier("FirstView") as FirstViewController
self.presentViewController(FirstView, animated: true, completion: nil)
}
The problem is your backToPrev method is instantiating a new FirstViewController, which is not the same instance you came from. You are not really going back to the original one, you are showing a new one. This is not what you want.
The proper way to do this is to embed the FirstViewController in a navigation controller, then push the addNew controller onto it. When you use a nav controller, you get the Back behavior for free.
Hopefully you are using a storyboard? Select your FirstViewController, go to the Editor menu and choose Embed in Navigation Controller.
In your toAddNew, instead of presentViewController use self.navigationController.pushViewController to push your addNew controller.
There's an even easier way to do this last step, using segues. You control drag in the storyboard from your button in FirstViewController to the addNew controller and create a Show segue. This will automatically show your addNew controller when the button is touched. With this approach, you will want to remove your toAddNew IBAction and the connection since it's redundant.

Resources