Can anyone tell me how to maintain the state of a view even while navigating through different views. I have a main view controller that has some button interaction and label changes with those interactions and I want to maintain those states while the user navigates to different pages.
It is not a good idea to "save" ui object, it is instead better to save the data you want to use somewhere (like a file) and get it when needed
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The app I am making has multiple pages which the user swipes between. I need the user to be able to press a button and that create a new page in the app, and then also for the user to be able to delete that page of the app. Is there a way to generate/delete a view controller while the app is in use? Or do I need the view controllers already to exist and somehow lock/unlock them when the user adds/deletes them?
You don't have to create all the view controllers already and somehow lock/unlock them when the user adds/deletes them.
You can use UIPageViewController for this purpose. Using UIPageViewController you will able add and delete view controllers.
Another way of implementing the same feature without the use view controllers as page is by using a UICollectionView with its cells as page and paging enabled. Here in this case the size of the collection view cell be same as the size of the screen.
To have a snapchat like multiple view controller you could probably use a UIPageViewController with your custom views or a scroll view with paging enabled.SwipeView also seems like a nice implementation. see this stack overflow post for some other options and some implementation methods.
I am trying to create an app for iOS using Swift but running into problems with the very basics.
To keep it simple I just want the app to initially be a single view application with a button and some sort of list view on the page. I believe a TableView is what is recommended here. When I click the button, I just want it to populate the list/table view with some entries, that's it. To start with, I don't care if these entries are hard-coded, I just want to get something working.
I have been looking at different samples but I am getting confused. Some of them seem to suggest using a TableViewController others don't. When I use a tableview controller, the UI I had created seems to get completely replaced with just an empty tableview list and the button is gone.
I previously have developed apps in Windows phone and found it a lot easier. I'd just add a listview object and in the click method of button, add the items programmatically etc. But this is my first time trying to create an iOS app and it seems a lot more confusing. There are delegates, controllers, views all seemingly needed in order to do something very simple.
Can anyone give me some basic step by step instructions about how to add a tableview to an application and load some data into it through a button click?
Make sure you are clear about the difference between a view and a view controller.
iOS uses the MVC design pattern (Model View Controller).
A view object displays contents to the user and responds to user interaction.
A model object stores state data.
A controller object drives the app logic and mediates between the model and the view.
A UITableViewController is a special subclass of a UIViewController who's job is to manage a table view. It has some extra support in it that makes it a good choice for managing a table view, BUT... there is one annoying thing about it. It is designed so the ONLY view it can manage is a table view. You can't use a UITableViewController if you want to add buttons, labels, and other UI elements to your screen outside of the table view.
What I usually do is to create a create a table view controller, create a separate regular view controller, add a container view to the regular view controller, and then use an embed segue to embed the table view controller inside the view controller. (you just control-drag from the container view to the table view controller.) That way you get the best of both worlds. You may want to create a protocol that the table view controller would use to communicate with it's parent view controller.
You should be able to find a tutorial online on setting up a table view controller as a child of another view controller using container views and embed segues. It's quite easy.
Is there a way to prevent swiping to one specific page in UIPageViewController
In my case, I need the left page just to be accessible sometimes,
Thanks!
No.
You will need to set up your page view controller without the page in question, and then add it when you want it to be available.
I would suggest changing your design. Page view controllers aren't intended to handle a case where the set of pages displayed changes. The real world analogy is a book where a page appears sometimes and not others. It doesn't make sense.
Instead you might want to present a modal view controller when you want this special-case VC to be available.
There's a particular control which I'm trying to build properly. I refer to it as an ImageTile. It's basically a little square box, which, when the user taps it, will present the user (via an action sheet in a popover) the option of selecting an image from the library, or taking a photo. Depending on the response, I then either present the UIImagePickerController inside a popover (for selecting an image) or modally (for taking a new picture). Once they take/select the image, I have a modal view which appears and allows them to edit the picture in a few simple ways. When they finish editing, the modal dismisses, and the original ImageTile, rather than being a blank square box, gets filled up with the user's edited image.
The issue is that this ImageTile control is going to be used profusely throughout several different parts of the application, across numerous View Controller hierarchies, and so on... and I really want it to be a basically totally self-contained unit, such that whenever I stick an ImageTile inside a UIView onscreen, all the above functionality is handled by the ImageTile itself.
Initially, I made it a UIViewController subclass (so it could present modals etc), and just added its view as a subview of a "holder" view onscreen. I know this isn't recommended, as the controller isn't part of the VC hierarchy then... and also, I wound up with some really weird behavior regarding things like autorotation, especially when the camera was involved.
What's the "right" way to implement something like this?
I think what you've done by making it a UIViewController subclass is correct. You should just use the methods that UIViewController exposes for adding child view controllers, such as - addChildViewController:.
You will also note that Interface Builder has a Container View object designed specifically for holding a place in the hierarchy for a child View Controller:
I apologize in advance for not being able to efficiently describe my problem statement. But, I shall include a link to an image to better describe what I'm looking for. Basically I have a Viewcontroller with a TableView inside it and I have a toolbar on top with three bar button items on it. Now what, I want is to be able to have a functionality whereby the user taps on any of these buttons and we go to different views. Now, I would like a design where if possible I stay on the same screen and render the information in the tableview below depending on which button has been pressed. Visually, I'm trying to go for an effect where the button that is pressed is shown as being depressed and information is rendered and on pressing a different button a different view is rendered. I'm familiar with attaching different view controllers to all the buttons and then segueing into those viewers. However, I would like to know if there's a way in which I can stay on the same view controller and just use sub views. If there is, how can I do this from storyboards? Again,, I apologize for being verbose, my picture should hopefully be able to tell you what I'm trying to do.
The link to what I'm trying to achieve: http://imgur.com/GM5eH
Well, one basic solution is simply to add these other views in your controller. Now that subview is set to hidden on viewDidLoad:. Then just create an action, and show the subView. You can size that view however you want, and play around with the other view as well.
Now, there might be a better way to do this, but that is how I would do it.
EDIT - Concerning Apple's method on Calender
Now, I have never tried anything like this, so this is all theory.
First, you create three classes. Each with it's own custom view. This view should be the size you need it on the other (Main View). You can set the size to freeform in the Interface Builder.
Once you have that done, you head to your main view. That view will have the three buttons. Set an IBAction for each of those that creates an instance of each view and places it on the screen. (I am not sure how to accomplish this, but I am sure there is a way. Take a look here: Objective-c Adding subViews in my controller
You should dealloc each view after you head to another view as well for memory management.