#ios tuts

Una de las ventajas de iOS 5 fue la incorporación de Twitter de forma nativa en el sistema. Esto hace la vida más facil a aquellos desarrolladores que quieran interactuar con Twitter a través de sus Apps.

Hace algunos días que empecé esta serie de tutoriales de programación para iOS de Ray Wenderlich y la verdad es que valen cada dollar que he pagado. Por 54$ tendrás acceso a 4 tutoriales en los que desarrollarás una App completa en cada uno de ellos.

Lo que más me está gustando es que los contenidos están actualizados (iOS5, StoryBoards, etc...) y la presentación muy currada (Todo en HTML).

In some of my tutorials on MobileTuts+ I go through explaining XIB-less development and how to make your interfaces sans Interface Builder. What I demonstrated was 99% XIB-less and there was one main XIB left, the MainWindow.xib.

At the time I was unaware of a nice method of removing this XIB. However, after reading through some posts there is an easy way to get rid of that last XIB.

Step 1: Info.plist change

Open up the PROJECT_NAME-Info.plist in your project. Locate the “Main nib file base name” row in the dictionary and give it a good ’ol delete. Save the file.

Step 2: Changing main.m

Next, if you are already 99% XIB-less then go ahead now and delete MainWindow.xib. If you have view controllers setup in MainWindow.xib then you will need to move them to the Application Delegate file. See Beginning iOS Development video #3 on Interface Builder for more information on how to do this, seek to 30:00 in the video and after that then delete the MainWindow.xib.

Open the main.m (in Other Sources) file in your project and find the code shown below:

And here is the code after the change:

So lets have a look at the difference. On line 6 in the code we have the UIApplicationMain method which if we look at in the documentation says:

This function is called in the main entry point to create the application object and the application delegate and set up the event cycle.

It accepts 4 arguments. The first 2 are passing the arguments through from the main() method. The last 2 allow you to specify the “principal class name” and the “delegate class name”. The principal class name is the name of the class that the Application Delegate inherits from, in this case its UIApplication. Finally, the delegate class name is the name of the class that we create so the Lap Timer application’s Application Delegate is called “LapTimerAppDelegate”.

Once the change is made in main.m, as illustrated above, then its time to move to the last step.

Step 3: Creating the window in code

Since the MainWindow.xib file is no longer available we have to create the window used throughout the application. To do this it’s a simple 1 line addition to our Application Delegate.

At the top of the main application initialisation call in the Application Delegate the window is allocated and initialised. The window’s frame is set as the bounds of the current device’s main screen.

Check your Application Delegates header file and make sure the UIWindow property is no longer an IBOutlet.

Mark Hammonds (MobileTuts+ Editor) and Myself have started a screencast series focussing on starting iOS Development. It's goal is to go from Day 0, from installing XCode through to development topics such as Data Retention using Core Data, UIKit objects and all of the necessary information about the iOS SDK to get anyone started.

It has been interesting producing these screencasts. It has definitely taught me a few things and corrected some wrong assumptions I had about how things in the iOS work. By far the hardest thing is making sure the information I give out is correct. This usually ends up in a screencast being re-recorded 4 times and lots of late nights in documentation but the results are awesome.

If you have been watching this series please drop a comment on what you think about it, good or bad I want to hear it :)