I have multiple view controllers which should load a specific view like in this drawing. I defined that view in the storyboard as a separate view controller. The reusable view controller has some methods which make the view work. What's the best way to do this?
I tried using addSubview method but the IBOutlets won't initialize. Please help me.
You probably want to use a container view.
With a container view, you can embed different view controllers in the same view. Hooking them up is really easy, and can be done within the storyboard.
Related
So I have a main view controller...
and two view containers. Vcon1 and Vcon2
I have them talking to each other via delegates however I'm not sure how to change the view controller displayed...so a tap on a button in Vcon1 will change the Vcon2 to have a new view controller...
I have a navagation controller in Vcon2 however I'm not sure I want a "stack" of view controllers in there...just want to swap out one for another.
Any suggestions appreciated..
If both of them have been added as subviews on the parentController's view, it's just a matter of calling bringSubviewToFront.
Else you can remove one of the view controllers, and proceed to add the other one. You can read more about view controller containment at objc.io
I have three view controllers each under the same custom view controller class, and a page view controller. I want to be able to reuse these three view controllers but with different content on their subviews. However, when I try to instantiate one of these view controllers from the page view controller using [self.storyboard instantiateViewControllerWithIdentifier:identifier], with a method to find the subview by tag right after, the subview returned is null. Is there some way I can get the subview by tag right after instantiating the view controller programmatically?
A view controller's views don't get created until it is about to be displayed. They won't be created after the call to instantiateViewControllerWithIdentifier:
You should put code that accesses the view controllers views in viewDidLoad, viewWillAppear, or viewDidAppear.
You should not try to manipulate a view controller's views from an outside object. That violates the principle of encapsulation, an important principle of object-oriented design. (It also often doesn't work, as you found out.)
If you need do things to the views programmatically you should add one or more public methods to the view controller and call those methods to ask the view controller to make adjustments to its views.
Can any one explain when should we add a UIViewController as ChildViewController?
What is the benefits of adding it as ChildViewController instead of subView?
Please help me to understand the purpose of ChildViewController.
When you add a view controller as child view controller, the parent view controller will hold a strong pointer to the child view controller so it doesn't get released instantly. This does not automatically add child's view to parent's view. So you will have to call them both.
I only used it when I needed to create multiple view controllers to be inserted in another view controller and didn't need to directly access it.
its all about UI and code management if you are using subview to achieve what you want to implement inside your app you need to code for your view inside same viewcontrollers class but something interesting i found by creating childviewcontrollers.
empowered to work on a seprate viewcontroller will invoked along with its parent viewcontroller along with its seprate class.
infinite controllers that will be updated tapping a button.
Creation of childViewControllers can be achived by implementing containerView.
or you must have a look of this link hope its helpful to understand.
I know there is the common practice in iOS development of having one UIViewController presented on the screen whose view is loaded from a XIB which will contain all the UIView subclasses in it.
While I was working on a pretty complex widget for an app, I decided to make the widget subclass a UIViewController instead of a UIView. This was because I thought a UIViewController was essentially a UIView with some helper methods around it. Then I could create a XIB for it (I know UIViews can have their own XIBs too), load the views it contains, place ITS view in the presented parent VC's view, and lay it out.
This works fine so far, but I'm wondering if this is bad practice and if I should just subclass a UIView instead and give it a normal NSObject controller. I am seeing some problems with this and I was wondering if anybody could address concerns I have with this approach?
EDIT NOTE: The widget VC does NOT relate to the VC view it is in and is reusable on ANY screen. So the answer is not subclassing the widget VC with the parent VC. The widget is INSIDE the parent VC, but it is NOT a parent VC.
EDIT NOTE 2: I am NOT using Storyboard. Only Autolayout, XIBs, and ARC.
Why can't we have VC's in VC's?
1) Can VC's be simply dropped into ANOTHER VC's XIB and be loaded easily as a subview?
2) I read here: When to use a UIView vs. a UIViewController on the iPhone?
The top answer explains how the VC controls rotation of the screen and laying out the subviews again, so if you add another VC, then the system will automatically think that THAT is the main VC and will attempt to rotate it instead, causing problems. Is this true? Or is he just talking about if you somehow got into a state where 2 VC's were "presented"? I wasn't sure if his answer applied to VC views that were SUBVIEWS of other VC views.
3) In general is this good practice? It certainly seemed more reasonable as it made loading the subview VC's view much easier.
Thanks!
It's absolutely fine. The answer to your problem is ContainerView.
Container View defines a region within a view controller's view subgraph that can include a child view controller. Create an embed segue from the container view to the child view controller in the storyboard.
You almost got it right. Yes, it's good to make a view controller for what you needed. But you shouldn't just add it's view to the parent view, you should also add the view controller as a child view controller of the first view.
You can add many views controllers as child view controllers of a view controller.
You can learn more about this here.
I have encapsulated all my table view logic on a UITableViewController that is linked to a view. This was done using storyboards.
I would like to embed this logic and view within another view controller / view (kind of like a header information with a scrollable table beneath.)
I have the following components:
CustomViewController which is linked to a UIView (dragged in from storyboard)
CustomTableViewController which is linked to a UITableView (dragged in from storyboard)
Essentially I am trying to mimic the scenario of the Stopwatch in the iOS clock app
What is the beast approach to this?
How is it done programatically?
Can this be done on the storyboard somehow?
Any help would be greatly appreciated. Thanks
Ok figured it out. This solution is iOS 5 specific since this feature was added there. This method works with storyboards.
Setup: The intention is to host one view controllers view and logic within another controller.
Since there is no intrinsic way to reference the child view controller in the storyboard, we need to give the view controller a name. This can be done by filling out the "Identifier" attribute on the controller in the storyboard. NOTE: Make sure you are giving the controller the identifier and not the controllers view.
Instantiate the controller you want to aggregate. This can be done from the hosting controller.
UIViewController *controller = [self.storyboard instantiateViewControllerWithIdentifier:#"ControllerIdentifier"];
Add the child controller to the parent controller
[self addChildViewController: controller];
Add the child controllers view to the parent controllers view. Note if you have a place holder view in the parent controller you wish to add the child view to, then this is where you do it. Here I add it the a UIView called stage in the parent controller.
[self clearStage];
[self.stageView addSubview:controller.view];
presentedController.view.frame = self.stageView.bounds;
And that is it. Pretty simple. I have used it successfully with switching controllers and view in a home made tab control. The sub controller enlists its views in the view lifecycle, so the viewDidLoad, etc all work as expected in this child view controller.
Hopes this helps someone.