This question is mostly about how I should structure my app. When the app loads the user can select from a list of videos to play, however the actual video player is on a different view controller. At the moment I am just keeping that view controller in memory so that the video can play continuously while the user is navigating throughout the app.
So the problems is that if the user selects a video before loading that movie view controller, nothing will happen of course.
How should I structure my app so that the video can play continuously whether or not the movie player view controller is held in memory? Is this possible?
I'm not 100% sure what you're trying to do; but a default project created in XCode will "Programatically load view on app didFinishingLaunching" without any further coding needed.
Generally you should structure your app with an initial view or view controller (like a navigation controller); and start any visible actions in the "viewDidLoad" method of the target view.
In your case, I would recommend loading straight to the video controller first; and then programmatically segueing to the video selector view if no video is selected.
Usually, I create a structure like this in my projects, I think you need to take a special look in OverlayViewController, check out a example:
MainViewController - As rootViewController
|- content (Any view controller to be presented, yes inside MainViewController)
|- OverlayViewController (a view controller over content )
This structure allows you to change contents without change entire hierarchy.
At MainViewController you will need a method to change current content to another, there is a simple example of how can you do that:
// PS I'm not sure if this will work in the first try, I wrote from my mind right now :)
func changeViewController (controller: UIViewController) {
let from: UIViewController
if childViewControllers.count > 0 {
from = childViewControllers.first as! UIViewController
}
else {
presentViewController(controller)
return
}
let transitionContext = SomeViewControllerContextTransitioning (
fromViewController: from,
toViewController: controller
)
transitionContext.onAnimationComplete = { success in
if !success {
// TODO: Error fallback
}
else {
from.view.removeFromSuperview()
from.removeFromParentViewController()
controller.didMoveToParentViewController(self)
}
}
from.willMoveToParentViewController(nil)
addChildViewController(controller)
SomeAnimator().animateTransition(transitionContext)
}
And finally, in your MainViewController you can observe or control your video playback.
I hope this can help you.
Related
I'm trying to make a custom ContainerViewController, but due to lots of difficulties with the ViewController transitions and making everything interactive, I've decided to mimic that functionality myself.
What I basically want to do, is have a paginated UIScrollView (the HeaderView) on the top control different another UIScrollView (the ControllersView) below that contains ViewControllers as pages so that as you swipe to a new page on the HeaderView, it also swipes to the next viewcontroller on the ControllersView. This is what the setup would look like.
My question is, is there anything wrong with having the aforementioned setup? All I'll do to add the view controllers to the ControllersView is just something like: controllersView.addSubview(pagecontroller1.view).
Some posts online seem to say that "the appropriate ViewController functions won't be called" or whatever. What do I seem to be missing here? I'm guessing there's a lot of dismissing and admitting of ViewControllers that I need to call every time a ViewController is out of frame right?
To clarify the question: Is it ok/efficient to do this? Should I be calling some viewWillAppear/disapper functions when the VC's get in and out of frame? If so, what should I call? I'm realizing that if I were to set things up this way, I need to manage a lot of things that are usually handled automatically, but as I mentioned before, custom ContainerViewControllers have failed me and I'm going with this.
PS. If you seem to still be lost on how this will look like, see my previous question here where I originally wanted to use a Container ViewController. There's a much better mockup there.
You can add and remove VC In Container Views
For - Is it ok/efficient to do this? Should I be calling some viewWillAppear/disapper functions when the VC's get in and out of frame? If so, what should I call?
As, We need to call WillAppear and Disappear Func when Adding and removing a VC , Thus Try using below Functions That will Handle these Responses
I use the Two specific Functions to add and remove Controller in ContainerView/UIView/SubView in ScrollView inside a UIView
To Add
private func add(asChildViewController viewController: UIViewController)
{
// Configure Child View
viewController.view.frame = CGRect(x: 0, y: 0, width: self.firstContainer.frame.size.width, height: self.firstContainer.frame.size.height)
// Add Child View Controller
addChildViewController(viewController)
viewController.view.translatesAutoresizingMaskIntoConstraints = true
// Add Child View as Subview
firstContainer.addSubview(viewController.view)
// Notify Child View Controller
viewController.didMove(toParentViewController: self)
}
To Remove
private func remove(asChildViewController viewController: UIViewController)
{
// Notify Child View Controller
viewController.willMove(toParentViewController: nil)
secondContainer.willRemoveSubview(viewController.view)
// Remove Child View From Superview
viewController.view.removeFromSuperview()
// Notify Child View Controller
viewController.removeFromParentViewController()
}
Creating Object
private lazy var FirstObject: firstVC =
{
// Instantiate View Controller
let viewController = self.storyboard?.instantiateViewController(withIdentifier: "firstVC") as! firstVC
// Add View Controller as Child View Controller
self.addChildViewController(viewController)
return viewController
}()
For - controllersView.addSubview(pagecontroller1.view)
Answer - Yes Approbate func wont be called if pagecontroller1 is not loaded in to memory stack, to load that you need to notify pagecontroller1 that it is going to be added to memory stack as Child View , Just as We initiate a Controller and basically notifies the Controller to get its component loaded to memory stack to get some memory allocations
For Question - Is it fine to nest a UIViewController within another without using addChildViewController?
Check apple Documentation - https://developer.apple.com/documentation/uikit/uiviewcontroller/1621394-addchildviewcontroller
This is necessary just as to notify the controller who is going to be added in Another Parent View as Child
Sample Project
https://github.com/RockinGarg/Container_Views.git
Or
https://github.com/RockinGarg/ContainerView-TabBar.git
If Question is Still not answered Please Tell me what Func Exactly you want to handle by yourself
I have a progress bar (with its own controller). This bar is supposed to be shown in different views depending on which view is visible. As the progress will be same, If possible I don't want to create many progress bar in many views rather I want to use same instance in all these views. Also in that way when I need to change any property of the progress bar it will be reflected commonly, which is required.
Please suggest me how can I use this common view. And also if my strategy is wrong, what would be the better design for such scenarios.
1) Well you have 2 options. You can declare a new Class ViewBox (or whatever name) and then use that inside your code
First View Controller
var box:ViewBox = ViewBox()
When you segue or transition to your next screen, you can have a predefined variable var box:ViewBox!. Then say when you press a button, the button has a function called transition.
//Now setup the transition inside the Storyboard and name the identifier "toThirdViewController"
override func prepareForSegue(segue:UIStoryboardSegue, sender:AnyObject?) {
if(segue.identifier == "toThirdViewController") {
var vc = segue.destinationViewController as! `nextViewController` //The class of your next viewcontroller goes here
vc.box = self.box
}
//Since The SecondViewController doesn't need ViewBox, we don't need it there.
}
where
nextViewController:UIViewController {
var box:ViewBox!
}
Or you could do a much simpler way and that is to look up a UIPageViewController :)
I'm working in an app that logs in an user if there isn't another user already logged in at launch time. This way the first view to appear should be the Login View. But in the case there is a logged user already, the first view appearing should be the main menu. Im handling this with the viewWillAppear function and it's working, but I don't know if this is the correct approach or how it should be handle in this situations.
Here is my code. My first view is MainMenuVC in which I control if there is a logged user or not, then I choose if stay in main menu view or push my login view.
class MainMenuVC: UIViewController {
override func viewWillAppear(animated: Bool) {
if (UserMgr.users.count == 0){
var vc1:LoginVC = self.storyboard?.instantiateViewControllerWithIdentifier("LoginView") as LoginVC
self.navigationController?.pushViewController(vc1, animated: false)
}
else
{
//I do nothing so this view is loaded
}
}
I don't know if i should use another ViewController and implement the function loadView() to decide what view load, but the problem is make that view work with the story board and my navigation controller.
Any suggestions?
Basically you will have two different view controllers, one for the login screen (VCLogin) and one for the main menu (VCMainMenu). Now, in your AppDelegate there are methods which are called, when the app launches respectively when it appears. So, place the code checking whether a user is logged in there and make the appropriate view controller the root view controller, e.g.
let navigationController = window.rootViewController as UINavigationController
navigationController.rootViewController =
userIsLoggedIn ? mainMenuViewController : loginViewController
Basically, my app is laid out in the page format and I would like it to launch into the middle of the three pages. There is no way of setting a previous page segue, so I have been trying to do it in code.
I have the main view set to the first view, and I have tried a variety of methods to segue to the middle view as soon as the app is launched.
Here is the two ways I tried:
if segueCheck == true {
self.pushControllerWithName("budget", context: self)
self.presentControllerWithName("budget", context: self)
segueCheck = false
}
The first presents the view, but as a completely separate view, and the second replaces the first view with the middle view.
Does anyone know how I can launch into the middle view and allow the user to swipe left and right of it?
Thanks.
WKInterfaceController's becomeCurrentPage() should be what you're looking for.
Let's create a new class for the center view controller, CenterPageViewController, and change its initWithContext: method as follows
import WatchKit
class CenterPageViewController: WKInterfaceController {
override init(context: AnyObject?) {
super.init(context: context)
super.becomeCurrentPage()
}
}
Now let's set the Custom Class for the middle page in your storyboard to CenterPageViewController
and finally hit run.
You won't be able to get rid of the initial transition from the left page to the center page, but the app will finally begin on the middle page.
Update Swift 3.0
class CenterPageViewController: WKInterfaceController {
override init (){
super.init()
super.becomeCurrentPage()
}
}
This will works...!!!
Thanks
The new way to do this in watchOS 4 and higher is:
WKInterfaceController.reloadRootPageControllers(withNames:
["Controller1" "Controller2", "Controller3"],
contexts: [context1, context2, context3],
orientation: WKPageOrientation.horizontal,
pageIndex: 1)
Now you don't get the annoying animation when using becomeCurrentPage() when you want to start with the middle page.
I am using the navigation controller to go back from one view to previous view using the code below.
ChildViewController.swift:
self.navigationController.popViewControllerAnimated(true)
I need a way to detect that the navigation controller went to the previous view in the actual previous view like below.
ParentViewController.swift:
func backWasPressed(viewControllerIdentifier: String!) {
// if back was pressed from this view controller and not from any other view
if viewControllerIdentifier == "ChildViewController" {
// do stuff here
}
}
Is there anyway to do this?
Take a look at UINavigationControllerDelegate
You don't need to know this. You may think you do, but you don't. This entire proposed architecture is specious:
func backWasPressed(viewControllerIdentifier: String!) {
// if back was pressed from this view controller and not from any other view
if viewControllerIdentifier == "ChildViewController" {
// do stuff here
}
}
If a pushed view controller has some info to communicate to a view controller further down the stack, that is the job of the pushed view controller when it is popped. It knows it is being popped, and it knows how to access the other view controller (and you can use a delegate architecture if there's any doubt about that), so the problem is properly solved in that way. It's exactly the same as when a presented view controller needs to communicate back to its presenter at dismissal time.