However, this time iOS Code Camp will go over 6 weeks instead of 3 so you get twice as much time to get one on one help from me.

Also, we are going to have weekly group coaching sessions now and these will take place each Wednesday.  These are primarily a Q&A time but I will have some more things to say about the content covered in the week in which the coaching call takes place.

Keep in mind that the content itself is self-directed so you can go at your own pace  and the schedule I’m about to show you is more of a suggestion.  Considering work and family, this is what I think most people can really do well in the time period.

Ok, here is the schedule:

iOS Code Camp Schedule

Each week you will go over two or three modules at your own pace. Throughout the week I will answer any questions that you have through on a Base Camp site set up just for iOS Code Camp. If the question involves code from the labs I’ll upload a video showing you how to fix your errors or otherwise get the lab complete.

For all six weeks we will also have a webinar scheduled for each Wednesday at 2:30=3:30 Eastern Time. Here we will have a general Q&A session, coaching and expand on the material that is covered for that week.

Here is the list of modules that we will cover each week:

WEEK ONE

1.1 – Mobile Apps, XCode 4, Interface Builder, Hello World

This is the introductory session where you will find out the low-down on the current mobile development universe. You will also be exposed to the iOS SDK for the first time with two Hello World examples using XCode, Interface Builder and even code.

1.2 – Objective-C Object Oriented Programming

Here will be go over the syntax of Objective-C which is the programming language that you will use with iOS SDK. We will also cover some advanced topics like blocks in addition to more traditional object-oriented concepts like classes, properties and methods.

1.3 – View Controllers, Singleton Model Classes, MVC

In the section on view controls, singleton and MVC you’ll explore the major design patterns behind UIKit. You will also see how to implement view controllers that work well with simple model classes as well as more complex Singleton classes.

WEEK TWO

1.4 – User Controls #1: Target-Action

The first section on user controls introduces the topic of user controls and who to work with them in Interface Builder. You will also learn the fundamental target-action design pattern that is used with many user controls like buttons and sliders.

1.5 – User Controls #2: Delegation

The last section in week one ends with one of the most important design patterns in iOS SDK called Delegation. Delegation is needed for user controls like the date picker but Delegation is used throughout iOS SDK in Foundation classes like NSXMLParser as well.

2.1 – Navigation and Tab Bar Multipage Apps

Apps that need more than one page for the users to see have special view controllers that give you powerful multipage features. In this section we will go over the two UIKit components that give your app multipage functionality.

WEEK THREE

2.2 – Table Views

Table views are the UIKit component that gives you the ability to list out tables of data one screen at a time. These common UIKit components are an integral part of most iOS apps. You will learn how to present information in table views and to use advanced features of table views in this section.

2.3 – Toolbars and In-App Email

Rounding out our discussion of UIKit are toolbars. Toolbars are powerful UIKit components that help us organize sets of functions and present them to the users. In the lab, you will wrote your own iOS app that helps email with a data attachment.

WEEK FOUR

2.4 – Core Data I Introduction

Core Data is the native database solution for iOS and it’s a huge topic. In this section, you see how to include Core Data into your projects and add Core Data functionality to your model.

2.5 – Core Data II Advanced Features with Universal Apps

Here we go over advanced Core Data features. Part of this section includes pointers on how to incorporate Core Data and UIKit into the iPhone portion of a universal app. This is where you see how it all comes together and you will see how to share your model between your iPhone and your iPad app.

WEEK FIVE

3.1 – Cloud Computing & Web Services

Connecting to the cloud is becoming increasingly essential these days. We’ll talk about the built in features that iOS has to work with the cloud (Internet web services). Also, we’ll go over some open source and other third party frameworks that are available to make it easy to use the cloud in your app.

3.2 – Making Magical and Responsive Apps with Threading

Here we go over some design considerations that should be taken into account when polishing your app. Part of this is making sure your app is responsive and so we go over how to use multi-threading to do this.

3.3 – Split View, Popovers and iPad Apps

Here is where we go over the iPad-specific features of iOS. We will use the app from 2.5 and add the iPad features to the universal app that we already started.

WEEK SIX

3.4 – Core Location and MapKit

iOS apps are uniquely able to get location information from their surroundings and many cool app ideas use this feature. We are going to go over Core Location which locates an iOS device in the world and also MapKit which is the embedded Google map feature developers can add to their apps.

3.5 – Mastering iOS App Development

Learning iOS SDK is only one step in the process of being an app developer. This could be the beginning of a lifelong obsession, passion or journey. In this module, we talk about what you need to do to become a master iOS developer.

What you need boils down to three things:

• Mac Computer
• iOS SDK
• Software Development Skills

Mac Hardware

This one is always the hardest for some people to swallow: look, you need a Mac to do iOS app development. The answer to the question I always get about “cheating” somehow and using a Windows or Linux computer is NO! No trying to install OSX on a Windows with VMWare or using a Hackintosh or whatever.

If you’re serious about doing iOS app development then you are going to need the right tools. You can see all your options for buying a new Mac on the Apple website. You can find a Mac Mini for as little as $599, but I would suggest a MacBook or MacBook Air so you can stay mobile.

iOS SDK

The next thing that you need are the tools that we used to make iPhone apps. The easiest way to get these tools is to buy them from the Mac App Store for $5.  The app that you need is called Xcode. When you buy and install Xcode you will get iOS SDK as part of the package.

Xcode is like a word processor for iOS code. Xcode comes with a code editor for Objective-C which is the programming language used for iOS and Mac apps. You will also get an editor called Interface Builder that you use to compose your app’s user interface. Interface Builder is a drag and drop solution so you don’t even need to write any computer code to make this work.

You will use Xcode for pretty much everything that you need to do to make iOS apps and Xcode runs only on Macs.

Software Development Skills

The apps that you see for sale in the app store are made of two things: content (pictures, music, movies, information) and code (the stuff that makes everything work).  Your apps will need content and code.  There are plenty of programs to help you create content: text editors, paint programs, etc.  But, to make it all work you will need code and that means you need software development skills.

If you already have software development skills, then you really just need to learn how to use the iOS SDK.  If you would like, I can help with that with my iOS Code Camp program.  iOS Code Camp is a coaching, training and mentoring program where I help programmers learn iOS SDK.  To get the most out of iOS Code Camp you should know some programming including object-oriented programming.

Key Software Development Skills

Generally speaking software developers need these skills:

• logical problem solving (ie: SUDOKU, puzzles, chess)
• creative building (ie: LEGOS, Civilization games, models)
• programming skills (ie: making web pages, robot instructions, macros, writing computer code)

You probably have some of these skills, one key thing that you really really need though is programming.  Programming is simply the process of giving instructions to a computer.  The trick with programming is learning the rules and using the tools that are available to you to be an efficient programmer.

To start learning programming generally, you can use your Mac and Xcode to learn Objective-C.  You can go through my free eBook, Beginning Objective-C Programming, to get started as an Objective-C programmer.

iOS App Development Skills

The next step after learning programming is learning how to use the tools that Apple gives you to make iOS apps using the best practices and patterns available.  This is what most software developers spend their time: using tools from companies like Apple to create software for end users.  The trick is learning to use these tools.

iOS SDK comes with Xcode so you don’t need any additional stuff to get started with iOS SDK.  Here are the main things that you will need to master to develop apps:

• Objective-C Programming (OOP)
• Foundation (OOP features that make hard programming tasks easy)
• UIKit (code you use to work with the iOS interface)
• Interface Builder (tool used to compose interfaces)

How to Get iOS App Development Skills

The quickest way to get up to speed on iOS app development is to register for iOS Code Camp.  iOS Code Camp is a 6 week online training program that includes 60 hours of training.  I personally teach iOS Code Camp and answer questions throughout the day via a dedicated BaseCamp site that I set up for you and you get weekly coaching calls with me.

iOS Code Camp is also hands-on and practical.  You will leave after having made 15 iOS apps (including iPad apps) and if you get stuck I’ll help.  You will learn Objective-C and the essential iOS SDK topics like Foundation and UIKit.  Also, we go deep into advanced topics like Core Data and Web Services because you want to leave iOS Code Camp with the skills to make real apps.

Click here to get all the details about iOS Code Camp.

Computer Science is the study of abstraction – finding the best model for a problem and implementation – figuring out how to solve the solution mechanically.

Introducing the Computer Science With Objective-C Series

So, I got this idea from perhaps the most unlikely of places: the movie Julie & Julia, where the main actor writes a blog about cooking a new recipe each day from the famous cookbook by Julia Childs. I thought it would be cool to go through my old college computer science materials and try to solve the problems from the class using Objective-C. Kind of like the movie, except I’ll write once a week on this topic and not every day (because I’m not insane…).

I thought it would be cool to go through my old college computer science materials and try to solve the problems from the class using Objective-C.

But, while the idea started as a weekly log of attempting to solve computer science puzzles with Objective-C things have evolved. That’s because as I go through the materials I realized that computer science is more than programming – it’s a study of how we solve problems in general. This means that I may have to be more narrative and descriptive at times. My hope is that this will help you learn more about understanding the how and why of what we do when we’re creating iOS apps.

What Will You Gain From Computer Science?

Here are some of the benefits that I hope that you get from this:

What The Computer Science With Objective-C Series Is Not

This is not meant to be a how to guide to programming, iOS app development or Mac development. These topics are much more practical. Some of the paths that we go down in the computer science series will be more about expanding your mind and may or may not have practical applications. Its more about you and how you think.

To learn more about the mechanics of Objective-C programming you can look at my free eBook, Beginning Objective-C Programming.

If you are interested in making applications for the iPhone and iPad check out iOS Code Camp, my premier training and coaching program for iOS app developers. If you’re just a little bit curious about iOS app development and Objective-C programming you may simply poke around this site. The programming tutorials section is a good place to start out.

Computer Science vs Programming

As was mentioned at the top of this article: Computer Science is a study of abstraction and implementation. Programming is the process of giving a computer specific instructions. Usually, programmers think in terms of abstraction and implementation as part of the programming process. However, as a field Computer Science is a more formal study of the kinds of things programmers do; Computer Science may go beyond what a typical programmer thinks about on a daily basis.

What Is Abstraction?

This word sounds scarier than it should be, but don’t worry too much about this. In computer science, Abstraction is about creating the best model for a problem. This generally means thinking of a problem in the simplest way possible in a way that may be mechanically represented. Often, an abstraction is much easier to work with than the corresponding problem or situation that we are working with.

Data Models

As you work with abstractions more you will find ways of thinking about problems that you can use as a starting point. For instance, many people will use graphs as a way to create an abstraction. For example, think of a business guy graphing out what the performance of a product should be in order to be “successful”. Or think of your company’s organization chart of personnel.

Graphs are considered a data model. Data models are general abstractions used to represent problems. Another data model is logic. We use logic when we think of things in these terms: if A = B, and B = C, then A = C.

What Is Implementation?

While Abstraction has to do with coming up with a simple model of your problem, Implementation is the mechanical process of solving the problem. This could be something as familiar as solving a math problem on paper, a calculator or a computer.

Usually, software developers think of implementation as programming.

Data Structures

Data structures of the programming constructs that we use when representing data models. The idea is that if your data model includes list of some kind, then your programming language needs a data structure to represent that list.

In Objective-C, we have a data structure called an array, NSArray, which we can use to represent of list of objects. So, if my data model includes a list of weigh-ins that I’m tracking for my diet, I can use an array to store those numbers that represent my weight each day.

Algorithms

An algorithm is a precise series of steps that can be carried out mechanically. Algorithms are like recipes: you do one thing after another until the process is complete. Often times, programmers take algorithms and translate them into something that a computer can do using a programming language.

Algorithms are something that can be studied and made more efficient when needed. However, there is often a trade-off with algorithms when it comes to their efficiency vs simplicity. That is, a very simple algorithm may do the job and be understandable while a more complex algorithm may also do the job and more efficiently but be more difficult to design and understand.

Summary

Today we introduced the idea for this series: I’m going to go through my old computer science stuff and relate this to Objective-C and iOS app development. Wish me luck and let me know what you think of this idea below.

We also introduced some of the main ideas in the study of computer science: abstraction, implementation, data models, data structures and algorithms.

The answer is to use NSDateFormatter to create date formats and get data objects formatted as strings that you can present to your users.

You will specify date formatter dates using the Unicode data format patterns. So, let’s assume for the moment that you have today’s date set up:

NSDate *todaysDate = [NSDate date];

If you want to present this you would do something like this but with your own UI:

NSDate *todaysDate = [NSDate date];

NSLog(@"Today's date is %@", todaysDate);

The output would look like this if you did it right now with me:

Today's date is 2012-02-02 21:10:57 +0000

That’s not all that pretty is it?

But, let’s bring the date formatter into the picture so you can see how to get some control over this output. We can simple create a new date formatter using NSDateFormatter . Then we can specify any date format that we want.

NSDate *todaysDate = [NSDate date];

NSLog(@"Today's date is %@", todaysDate);
 NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; dateFormatter.dateFormat = @"EEEE, MMMM d"; 

Now, check out the output:

Today's date (formatted) is Thursday, February 2

Pretty cool right? So, I choose to output the date in a particular way but you can do whatever you want here. See the Unicode date format pattern reference to get more formats that you can use.

Huge Improvements To iOS Code Camp!

iOS Code Camp is my exclusive online training seminar. iOS Code Camp is an intensive training program plus live mentoring, coaching and community building delivered by yours truly via BaseCamp and GoToMeeting. This is where programmers go to learn iOS development as quickly as possible.

Last year, we did great with the 3 three intensive boot camp style iOS Code Camp. But, this time around I’m going to increase iOS Code Camp to six weeks (that’s twice as long!) and change the structure a bit to keep everyone even more focused on getting the coding “meat memory” down pat.

Mark Your Calendar for March 12th!

The next iOS Code Camp will start March 12th and go on for 6 weeks. Keep an eye on the How to Make iPhone Apps Blog, Mobile App Mastery Institute or on the newsletter mailing list to find out when registration opens. Remember seating is limited so I can give you the attention that you deserve.

Big Semi-Secret Project

Many of you might be wondering why my Twitter feed has been relatively quiet (with the exception of some timely observations about the constant Yo Gabba Gabba and Thomas the Train episodes my two year old insists on watching)…

Well – I’ve been working on a huge new book with a new publisher, APress. APress is a big time publisher and I’m very excited to be working with them on this book. While I don’t want to say much yet about the book (I’m not really sure what I can say actually) – I will say that the topic is iOS and Mac programming and you may find it useful as you move how this iOS app developer roadmap. The book will be published in the summer if everything goes right. Wish me luck!

That Wraps It Up For Now!

Remember, keep an eye out for iOS Code Camp if you are looking for a new career or direction or want to start your own software business. March 12th! Now, I gotta run back to my book!

What Course Was That?

The course was Symbolic Logic and it was simply a course that showed use the fundamental ways to figure out logic problems. Honestly, the entire class really boiled down to this:

If A = B and B = C then A = C

In the class, we would go over tons of situations and reduce them to logic statements written down on paper in pretty much the form you see above (but usually they started out more complicated). This process of breaking problems down into abstract statements that can be evaluated is what the study of logic is all about.

There was something about learning logic in this way, in its pure form, that really made a lot of sense. Really,

the lesson I learned here is that you need to learn how to solve problems before you can attempt to program a computer to solve problems.

What Does This Mean For You?

If you are early on your path to becoming a programmer and feel frustrated and perhaps distracted by all the glitz of the Objective-C iOS Mac Foundation programming world then you may need to get back to basics. My thought for you today is that you take a detour and learn about pure logic. Take some time to train your brain up in logical reasoning.

How To Train In Symbolic Logic?

The class I took in my university was all lectures, slides and handouts so I don’t have a great book recommendation. However, I would suggest looking up a course on logic at your own university or local community college. An alternative could be this book I found at Amazon: Being Logical: A Guide to Good Thinking.

Do You Have Any Good Book Recommendations For Learning About Logic?

NSString *string1 = @"A";
NSString *string2 = @"B";

if(string1 == string2)
     //do something
else
     //or not

NOTE: ^ the code above will not work…

But, that doesn’t work because strings are objects and if you want to compare strings you will need to use the NSString object methods that Apple has made available to you.

Testing For Equality With NSString

Most likely, you just want to see if your string is equal to another string. This is something that you can use in an if-then statement to direct the flow of your program. To do this you must use isEqualToString: function. This is something you send to the first string using the second string as a parameter. The result comes back as a BOOL (YES or NO) that you can evaluate.

See the example below:

NSString *myString1 = @"A";
NSString *myString2 = @"B";
NSString *myString3 = @"A";

BOOL isEqual = [myString1 isEqualToString:myString2];

if(isEqual)
     NSLog(@"%@ is equal to %@", myString1, myString2);
else
     NSLog(@"%@ is not equal to %@", myString1, myString2);

Looking For Prefixes and Suffixes

NSString also has two really convenient functions that you can use to find out if a string is at the beginning or end of your string. These two functions are called hasPrefix: and hasSuffix: respectively.

Check these out here:

NSString *name = @"Mr. John Smith, MD";

BOOL hasMrPrefix = [name hasPrefix:@"Mr"];

if(hasMrPrefix)
     NSLog(@"%@ has the Mr prefix", name);
else
     NSLog(@"%@ doesn't have the Mr prefix", name);

BOOL hasMDSuffix = [name hasSuffix:@"MD"];

if(hasMDSuffix)
     NSLog(@"%@ has the MD suffix", name);
else
     NSLog(@"%@ doesn't have the MD suffix", name);

Comparing Substrings With NSString

Finally, you can also compare substrings with the NSString function substringWithRange: . The first thing that you do is define an NSRange with the starting point and length of the string that you are interested in. Then you can use the first string's substringWithRange: function to extract the substring. Once you do this you can use the same comparison methods as we just discussed.

Here is an example of that in action:

NSString *alphabet = @"ABCDEFGHIJKLMONPQRSTUVWXYZ";

NSRange range = NSMakeRange(2, 3);

BOOL lettersInRange = [[alphabet substringWithRange:range] isEqualToString:@"CDE"];

if(lettersInRange)
     NSLog(@"The letters CDE are in alphabet starting at position 2");
else
     NSLog(@"The letters CDE aren't in alphabet starting at position 2");

So, that's it for comparing strings with NSString in Objective-C. Any thoughts or other ideas to help people to work with strings?

Get Today’s Date In Objective-C

Before we go any further, let’s make sure we are on the same page and can get a reference to today’s date. Oh yeah, we’ll call that day today.

NSDate *today = [NSDate date];

What you can do is create a new NSDateComponents object and then specify the amount of time that you would like to add or subtract from your date.

NSDate *today = [NSDate date];
NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
dateComponents.week = -1;
dateComponents.day = -3;

Now to get the date for one week and three days ago I need to get a reference to my system calendar first:

NSCalendar *calendar = [NSCalendar currentCalendar];

Then I can use the NSCalendar function dateByAddingComponents:toDate:options: to get the date from a week and three days ago.

NSDate *today = [NSDate date];

NSDateComponents *dateComponents = [[NSDateComponents alloc] init];

dateComponents.week = -1;
dateComponents.day = -3;

NSCalendar *calendar = [NSCalendar currentCalendar];
    
NSDate *previousDate = [calendar dateByAddingComponents:dateComponents
                                                 toDate:today
                                                options:0];

To see the results of the subtraction above write out the two date objects to the log.

NSDate *today = [NSDate date];

NSDateComponents *dateComponents = [[NSDateComponents alloc] init];

dateComponents.week = -1;
dateComponents.day = -3;

NSCalendar *calendar = [NSCalendar currentCalendar];

NSDate *previousDate = [calendar dateByAddingComponents:dateComponents
                                                 toDate:today
                                                options:0];

NSLog(@"Today is %@ and a week and three days ago it was %@", today, previousDate);

You will see something like this appear in your console screen:

Today is 2012-01-19 15:10:12 +0000 and a week and three days ago it was 2012-01-09 15:10:12 +0000

So What Do You Think?

Have you had any luck with this method of adding and subtracting dates in Objective-C?

Write Objective-C Code Using Arc From Any Text Editor

So, check out this code I wrote just with a text editor (no XCode at all):

#import <Foundation/Foundation.h>
int main (int argc, const char * argv[]){
 	@autoreleasepool {
		NSString *helloString = @"Hello World";
		NSLog(@"%@", helloString);
	}
	return 0;
}

It’s pretty refreshing to actually see the entire program here and in just one place without any fussy extras attached. You can test many Objective-C Foundation procedures like this.

Note that we are going to use ARC to compile here and that is why I can use the @autorelease keyword. If you are not using ARC then you may need to use the older NSAutoreleasePool instead.

Compile Mac Code From Terminal With ARC Using Clang

You can use the command clang to compile the code above. XCode will do something similar for you in the background, but its nice to see the general format. Here is what you would type into Terminal to compile your Mac app:

clang -fobjc-arc -framework Foundation main.m -o maccommandlineapp

Here is what all this stuff means: clang is the compiler that you must use if you want ARC. -fobjc-arc lets the compiler know that we intend to use ARC for memory management. -framework Foundation is linking us to the Foundation framework so we can import that into our Mac code and use Objective-C classes. main.m is the code file that you are compiling and -o maccommandlineapp specifies the output file.

How To Use Your Compiled Mac Program

Make sure that you are in the folder where you located your code file and compiled your program. Then, simply type in open maccommandlineapp. You will see the output in the Terminal window.

So – I am doing this post not to impart any great secrets from behind the iOS curtain. I’m curious about what YOU as a reader curious about iOS app development are looking for.  Take a second to think about it and just respond to this post with a question.  I’ll do my best to answer it or link you to a resource that will answer better than I can.

Ok, so What Do You Want To Know About iPhone, iPad & iOS Development?