I have a UIViewController that is presented in two ways, either modally or pushed on top of a navigation controller stack. The UIViewController contains a UITableView and a UIToolbar. When presented modally, i needed a way of showing a title for the ViewController, so I added in another UIToolbar, topToolbar. My problem is, whenever I push the UIViewController, I don't need topToolbar anymore, since the navigation tabbar already shows the title. When I set topToolbar's hidden property to true, however, my UITableView is not bound to the bottom of the navigation tab bar and there's space between the UITableView and the navigation tabbar, which doesn't look so good. I tried to call removeFromSuperview() on topToolbar instead of setting its hidden property to true, but that didn't work out, and topToolbar appeared under the navigation bar, and now i have two titles instead of one. Any idea on how this can be done? I can't add pictures, but here's my code for manipulating the appearance of the UIViewController based on whether it's presented modally or pushed on top of the navigation stack:
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
if itemBought != nil {
cart.items.append(itemBought!)
}
totalView.layer.borderColor = UIColor.grayColor().CGColor
totalView.layer.borderWidth = 0.5
totalLabel.text = "$" + String(format: "%.2f", cart.getTotal())
if let navBar = self.navigationController?.navigationBar {
//hide toolbar and tabbar
topToolbar.removeFromSuperview()
self.tabBarController?.tabBar.hidden = true
//hide shop button
var bottomItems: [UIBarButtonItem] = bottomToolbar.items as! [UIBarButtonItem]
if let index = find(bottomItems, shopToolbarButton) {
bottomItems.removeAtIndex(index)
}
bottomToolbar.items = bottomItems
}
}
I should also mention that i have a constraint on the UITableView that's basically: distance between UItableView.top and Top Layout Guide.Bottom is <= to the height of topToolbar, which is 44.
Any ideas?
When you present the View Controller modally, why not put it in a UINavigation Controller?
let navigationController = UINavigationController(rootViewController: myViewControllerInstance)
self.navigationController?.presentViewController(navigationController, animated: true, completion: { () -> Void in
//do something here when animation is complete if you want
})
Related
I have a UINavigationController with some UIViewControllers embed. The problem is when I start to push viewControllers. As you can see in the next image, the content view of the current viewController is overlapping the navigationBar:
In viewDidLoad:
func setupFront() {
navigationController?.setNavigationBarHidden(false, animated: true)
self.navigationController?.navigationBar.prefersLargeTitles = true
title = NSLocalizedString("customer_settings_profile_title", comment: "")
binding()
setupLanguage()
}
The problem was the autolayout. The top constraints of the views that I push weren't set to safe area.
Now it is and it works:
I have several view controllers and they are very complexed.
MainVC (embed with tab bar controller)
FriendListVC
ChatRoomUpperVC (embed with navigation view controller)
ChatRoomVC (NavigationViewController with embed in ChatRoomUpperVC) (only shows the tab bar)
ChatRoomQuestionVC (pushed from ChatRoomVC) (only shows the navigation bar)
MatchedWaitVC (pushed from ChatRoomQuestionVC) (hide both tab and navigation bars)
ChatVC (pushed from MatchedWaitVC) (only shows the navigation bar)
SettingVC
What I have to do is when I click the back button from the ChatVC, I should back to ChatRoomVC and show the tab bar on the bottom only.
I tried the code below but it shows the black screen and there is no tar bar neither.
override func willMove(toParentViewController parent: UIViewController?) {
if parent == nil
{
var viewControllers = navigationController?.viewControllers
viewControllers?.removeLast(3)
navigationController?.setViewControllers(viewControllers!, animated: true)
self.navigationController?.isNavigationBarHidden = true
self.tabBarController?.tabBar.isHidden = false
}
}
I guess you can use following hack to achieve what you want. In the viewDidLoad method of the ChatVC do:
override func viewDidLoad() {
super.viewDidLoad()
if let root = navigationController?.viewControllers.first {
navigationController?.viewControllers = [root, self]
}
}
This will remove the inbetween view controllers that are between ChatVC and ChatRoomVC. Now popping back (e.g. using the standard back button, or swiping from the left edge of the screen) will jump back directly to the ChatRoomVC.
EDIT
To show the tabBar again in the ChatRoomVC, add this to the viewDidAppear:
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
self.tabBarController?.tabBar.isHidden = false
}
This will ensure that as soon as ChatRoomVC appears on the screen, its tabBar will be presented, too.
I want to display some UI elements, like a search bar, on top of my app's first VC, and also on top of a second VC that it presents.
My solution for this was to create a ContainerViewController, which calls addChildViewController(firstViewController), and view.addSubview(firstViewController.view). And then view.addSubview(searchBarView), and similar for each of the UI elements.
At some point later, FirstViewController may call present(secondViewController), and ideally that slides up onto screen with my search bar and other elements still appearing on top of both view controllers.
Instead, secondViewController is presented on top of ContainerViewController, thus hiding the search bar.
I also want, when a user taps on the search bar, for ContainerViewController to present SearchVC, on top of everything. For that, it's straightforward - containerVC.present(searchVC).
How can I get this hierarchy to work properly?
If I understand correctly, your question is how to present a view controller on top (and within the bounds) of a child view controller which may have a different frame than the bounds of the parent view. That is possible by setting modalPresentationStyle property of the view controller you want to present to .overCurrentContext and setting definesPresentationContext of your child view controller to true.
Here's a quick example showing how it would work in practice:
override func viewDidLoad() {
super.viewDidLoad()
let childViewController = UIViewController()
childViewController.view.backgroundColor = .yellow
childViewController.view.translatesAutoresizingMaskIntoConstraints = true
childViewController.view.frame = view.bounds.insetBy(dx: 60, dy: 60)
view.addSubview(childViewController.view)
addChildViewController(childViewController)
childViewController.didMove(toParentViewController: self)
// Wait a bit...
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 2) {
let viewControllerToPresent = UIViewController()
viewControllerToPresent.modalPresentationStyle = .overCurrentContext // sets to show itself over current context
viewControllerToPresent.view.backgroundColor = .red
childViewController.definesPresentationContext = true // defines itself as current context
childViewController.present(viewControllerToPresent, animated: true, completion: nil)
}
}
I created a custom search bar and embedding it in the navigation bar, it appears but after I push another view controller, the search bar does not get replaced with the title of the pushed view controller. The search bar stays persistent throughout all views, instead of getting replaced with a title. Perfect example is Instagram search tab, you search for a person and click on the cell, their profile is pushed and the search bar is replaced with the custom title, back button, etc.
First VC
self.customSearchBar.tag = 4
self.navigationController?.view.addSubview(customSearchBar)
Second VC
if let nav: UINavigationController = self.navigationController {
if let searchBar = nav.view.viewWithTag(4) {
searchBar.removeFromSuperview()
}
}
You shouldn't place the searchbar inside the navigationcontroller view as this view is the same instance on all pushed viewcontrollers.
Add the searchbar to the the depending view controllers ui.
To add a searchbar on navigationBar, this is the way.
self.navigationController?.navigationBar.addSubview(customSearchBar)
To remove it when you push it to other viewController. Write the following code in the secondVC that is pushed inside it's viewDidLoad() function. Also, set the tag of customSearchBar to any number (TAG)
if let nav: UINavigationController = self.navigationController {
let bar: UINavigationBar = nav.navigationBar
if let searchBar = bar.viewWithTag(TAG) {
searchBar.removeFromSuperview()
}
}
In the question, the customSearchBar is added to self.navigationController.view. To remove it, you can do the following:
if let nav: UINavigationController = self.navigationController {
if let searchBar = nav.view.viewWithTag(TAG) {
searchBar.removeFromSuperview()
}
}
Edit:
Adding and removing a UIViewController's view as a subview of other UIViewController
// for adding
let viewController: ViewController = ViewController()
self.addChildViewController(viewController)
self.view.addSubview(viewController.view)
viewController.view.bounds = self.view.bounds // better to use autolayout here
viewController.didMove(toParentViewController: self)
// for removing
if let vc = self.childViewControllers.last {
vc.willMove(toParentViewController: nil)
vc.view.removeFromSuperview()
vc.removeFromParentViewController()
}
I have the hidesBottomBarWhenPushed = true set for one of my UIViewController's (call it ViewControllerA) that is pushed onto my UINavigationController stack. I also opt to show the bottomBar when I push a new ViewController ontop of ViewControllerA. Therefore I have:
class ViewControllerA: UIViewController {
override func viewWillDisappear(animated: Bool) {
self.hidesBottomBarWhenPushed = false
}
override func viewWillAppear(animated: Bool) {
self.hidesBottomBarWhenPushed = true
}
This all works fine.
When I push ViewControllerA, the bottom bar hides.
When I push any other ViewController, the bottom bar shows.
However, when I am traveling backwards in the navigation stack (aka hitting the UIBarButtonItemBack button), I cannot get the bottomBar to hide when I pop the navigation stack to reveal ViewControllerA.
What am I missing? Thanks!
Got it! Here's what worked:
class ViewControllerCustom: UIViewController {
init() {
self.hidesBottomBarWhenPushed = true
}
override func viewDidAppear(animated: Bool) {
self.hidesBottomBarWhenPushed = false
}
}
And then in every UIViewController's custom implementation of BarButtonItemBack pressed I check to see if the previous view controller (that will be popped to needs to hide the tab bar). Granted I abstracted this out into a general function so I didn't need to repeat code, but here's the concept. Thanks for the help figuring this out though!
func barButtonItemBackPressed(button: UIButton) {
var viewControllers = self.navigationController!.viewControllers as! [UIViewController]
if ((viewControllers[viewControllers.count - 2]).isKindOfClass(ViewControllerCustom.self)) {
(viewControllers[viewControllers.count - 2] as! ViewControllerCustom).hidesBottomBarWhenPushed = true
}
self.navigationController?.popViewControllerAnimated(true)
}
I believe the intended use of this property is to hide the bar when pushed. So, when your view controller appears after the top-most one is popped, it wasn't pushed on the stack, so it doesn't change the tab bar's appearance.
This leaves you with two options:
1) Keep the bottom bar for all view controllers. When text is being entered, the keyboard covers the bottom bar.
2) Hide the bottom bar for View Controller A, as well as any other view controller that is pushed on top of A.