I'm new to Xcode programming and I've been watching a couple videos here and there but one thing I never find on mine which the videos have. They have a file called "ViewController" (.h/.m). I don't have that, instead I have AppDelegate, RootView, DataView, and ModelController (all are .h/.m)
Choose the Single View Application template that contains ViewController. Or press command+N to create a new Cocoa Touch Class and make it subclass of UIViewController.
Related
I am experimenting with Interface Builder in Xcode 4.2 and iOS 5 on a old Mac.
In Xcode 3.2 there was always a MainWindow.xib file and it contained not only the File's Owner which was UIApplication IMHO, but also an App Delegate placeholder object.
I created a MainWindow.xib file using the Window xib template. The AppDelegate placeholder is missing, so I can't hook the window up to my actual app delegate object.
I suppose that I will need to add a placeholder object with it's class identity set to "AppDelegate" but couldn't figure out how.
Just drag out one of the blue cubes (called "Object") from the objects library and change its class to the class of your app delegate.
I am new to iphone development, and i'm currently using xcode 4.2.
I drew a UIViewController into the storyboard. I put some labels into the UIViewController. It is associated to a controller.m file.
How do I, from the viewdidload function of the controller.m file, update the text in the label?
I don't know how to get the variable name or handle name of the elements in the uiviewcontroller on the storyboard.
If you are creating things through storyboard, the easiest way is to create an IBOutlet property for each UI element. This creates an instance property for the UIElement which you can then reference in your code - to set state, get values, etc.
You can do this through Control-click-drag on the UIElement to your UIViewController.h file (split view: RETURN-Command-Option: to display counterparts). XCode will pop up a dialog enabling you to name it (the same gesture will also enable you to create IBActions - the function that is called when the UIElement gets interacted with). You can also Control-click-drag on the left sidebar listing of the UIElements in your ViewController if that is easier.
There are YouTube videos that show it better than my weak explanation. I was skeptical # storyboard/IB at first because I don't like UI magic and prefer to do things through code, or at least see the code that results from the magic, but it really does work pretty well and saves some of the tedium of UI coding.
One gotcha to be aware of: if you make an IBOutlet and then delete the UIElement, you will have code errors because of the errant reference. Those are easy to find and fix. The UIViewController object will also contain those references and will result in unpleasant crashes - so Control-click on the UIViewController object (or use the Inspector panel) and any element that has an orange triangle == broken.
First off, I will say i've spent 6 hours on this topic and have read everything the internet has to provide, which is why i came here.
I have converted to Universal, Xcode created the MainWindow-iPad.xib and everything seems fine.
Here are my questions:
1) What are the naming conventions for new iPad-specific xibs? Xcode created "-iPad" but i believe im supposed to be making them "~ipad". Why the difference?
2) (MOST IMPORTANT) After creating several "~ipad" xibs, Xcode seems to know to load these. So I'll copy the content in say, "RootViewController.xib"
and paste it in "RootViewController~ipad.xib". THIS IS THE PROBLEM: this new ~ipad xib has no outlets or referencing outlets!
I can't link the buttons on my page to anything. How do i do this without having a separate ~ipad .m and .h for everything?
Thank you guys for your help! I'm going to write a tutorial on this once I get this all working.
Just set the class of that ~iPad nib to be the same classname as the cooresponding iPhone nib. This is done in the inspector in Interface Builder. You may have to connect the outlets back up depending on the order you do things. I would think that if you copy the objects from the iPhone nib to the iPad nib AFTER you set the class, then the outlets would stay wired up.
Is there a convenient way to generate code from any new view controllers I've created on the storyboard? For example when you create a new iOS application, XCode will set up a skeleton class for your view controller.
Thanks!
I don't think so. You need to create a new ViewController subclass in XCode but uncheck the "Create Xib for this class" box (not sure if that is exactly what it says). Then select your newly made view controller in storyboard and change it to the class you just created.
Ok the skeleton you are talking about is just a template for your application. You are asking for a dynamic template generator from your storyboard and maybe Apple can figure out how to do this in a non distant future but in this moment I think you can't do that. After you created the storyboard file with your complex scheme you need to manually create all your viewController subclass you used in the storyboard. It's not a big deal ... I suppose your application doesn't have thousand ViewController so you can do it manually.
Apple are working hard to simplify developers job but Xcode can't do everything for you.
You can try to post this answer directly to Apple throughout the bugreport Apple website and post it as improvement to implement in future Xcode release.
Lets try it :)
I was using Xcode 4.1 and after upgrading to 4.2, things started to become out of date. I am using many examples from different books, such as Big Nerd Ranch Guides, which do not use Storyboards and the Windows-Based Application had been changed to "Empty" Application.
With these new changes, I feel like the books and tutorials I had been using to start have become outdated. In many of these examples, they say to write the methods and variables in the delegate header files for 4.1. With the new 4.2 Xcode, there is an AppDelegate and ViewController. Should I still be writing the methods and class members in the AppDelegate, or should I be now writing them in the Controller file?
I am confused. Does Apple now want us to create our controller and reference it through the delegate?
When your app is run, it creates an instance of UIApplication. You want to know things that only the UIApplication object knows (did we just get switched to the background? did we just open?) so you use the delegate pattern to get it. When you start a new project Apple starts you off with an already-assigned App Delegate. You can open up MainWindow.nib and inspect your App Delegate to see how it is connected to your UIApplication instance (File's Owner, in this case).
In general you only want to put code in there that has to do with the basic functionality of your app. Launch, quit, go to background and come to foreground are when you'll be doing things in the App Delegate.
Most everything else should go in your view controllers or model objects. Since 'delegate' is just a design pattern, your view controllers can be delegates of other objects. For example, if you present a UITableView, you will assign a view controller as it's delegate in order to respond to events such as selection and scrolling. Your app has many delegates, but it only has one App Delegate.
The AppDelegate is really just a "launcher" for your app. Ie: You shouldn't be writing much code in it at all.
If you're concerned with "set up" code, do it in your View Controller, under viewDidLoad.