ObjectiveC Tutorials

Objective-C Tutorials Roadmap

What is Objective-C?
- A general-purpose, object-oriented programming language.
- A superset of the C programming language.
- Primarily used for developing applications for Apple's macOS and iOS operating systems.
Why Objective-C?
- Historically the primary language for Apple platforms.
- Provides access to the Cocoa and Cocoa Touch frameworks.
- Understanding Objective-C is crucial for working with older codebases and understanding the evolution of Apple development (leading to Swift).
Setting up Your Development Environment:
- Installing Xcode (Apple's Integrated Development Environment).
- Understanding the Xcode interface.
Your First Objective-C Program:
- Creating a new Xcode project.
- Writing and running a simple "Hello, World!" program.

Review of C Fundamentals:
- Variables, data types, operators.
- Control flow (if, else, switch, loops).
- Functions.
- Pointers.
- Structures and unions.
Objective-C Syntax:
- Understanding the `@` symbol.
- Header files (.h) and implementation files (.m).
- #import vs. #include.
Basic Data Types:
- Primitive types (from C).
- Objective-C data types (e.g., BOOL, id, instancetype).
Memory Management (Introduction):
- Understanding the need for memory management.
- Introduction to Automatic Reference Counting (ARC).

Classes and Objects:
- Defining classes (@interface and @implementation).
- Creating instances of classes (objects).
Instance Variables and Properties:
- Declaring instance variables.
- Understanding and using properties (@property).
- Synthesizing instance variables (@synthesize - less common with modern Xcode).
- Attributes of properties (e.g., nonatomic, atomic, strong, weak, copy, assign).
Methods:
- Defining instance methods (-).
- Defining class methods (+).
- Understanding method signatures and selectors.
- Sending messages to objects (method calls).
Encapsulation, Inheritance, and Polymorphism:
- Implementing OOP principles in Objective-C.
- Subclassing and superclasses.
- Method overriding.

Introduction to Foundation:
- A core framework providing fundamental data types and services.
- Working with common classes.
String Handling:
- NSString and NSMutableString.
- Creating, manipulating, and comparing strings.
Collection Classes:
- NSArray and NSMutableArray.
- NSDictionary and NSMutableDictionary.
- NSSet and NSMutableSet.
- Working with collections (adding, removing, iterating).
Numbers and Values:
- NSNumber.
- NSValue.
Dates and Time:
- NSDate, NSCalendar, NSDateFormatter.
Data and Archiving:
- NSData.
- Serialization and deserialization.

Protocols:
- Defining a set of methods that classes can implement.
- Similar to interfaces in other languages.
- @protocol keyword.
- Adopting protocols.
- Required and optional methods.
Categories:
- Adding methods to existing classes without subclassing.
- Extending framework classes.
- Using the + syntax for category names.
Extensions (Class Extensions):
- Similar to categories but for adding private methods or properties within the same compilation unit.

Automatic Reference Counting (ARC):
- How ARC works.
- Understanding retain cycles and how to avoid them.
- Using strong and weak references.
- Using unowned references (less common in pure Objective-C, more relevant when interacting with Swift).
Manual Reference Counting (MRC) - Historical Context:
- Understanding retain, release, and autorelease (important for understanding older code).

Blocks:
- Anonymous functions in Objective-C.
- Using blocks for callbacks and asynchronous operations.
- Capturing variables in blocks.
- Handling retain cycles with blocks (__weak and __strong).
Concurrency:
- Understanding threads and processes.
- Grand Central Dispatch (GCD):
- NSOperationQueue and NSOperation (higher-level abstraction over GCD).

Using NSError:
- Standard way to handle errors in Cocoa/Cocoa Touch.
- Passing errors by reference.
Exception Handling:
- Using @try, @catch, @finally (less common for typical errors, more for programming errors).

Key-Value Coding (KVC):
- Accessing object properties indirectly using strings.
- valueForKey: and setValue:forKey:.
Key-Value Observing (KVO):
- Mechanism for observing changes to object properties.
- Observer pattern implementation.

Understanding Frameworks:
- Introduction to the Cocoa (macOS) and Cocoa Touch (iOS) frameworks.
Core Concepts:
- Delegation.
- Target-Action pattern.
- Notifications.
User Interface Development (Brief Overview):
- Introduction to UIKit (iOS) or AppKit (macOS).
- Working with views and view controllers.
- Connecting UI elements to code (Outlets and Actions).
- Using Storyboards and XIBs.

Bridging Header:
- How to use Objective-C code in a Swift project.
Objective-C Bridging to Swift:
- How Objective-C classes, methods, and properties are represented in Swift.
Using Swift Code in Objective-C:
- Understanding the generated Swift header file.

Runtime Programming:
- Understanding the Objective-C runtime.
- Dynamic method resolution, swizzling.
Core Data (Data Persistence):
- Introduction to Core Data for managing the model layer.
Networking:
- Using NSURLSession for making network requests.
Unit Testing:
- Writing tests for Objective-C code using XCTest.
Learning Resources:
- Apple's official Objective-C documentation (archived but valuable).
- Books on Objective-C and iOS/macOS development.
- Online courses (Udemy, Coursera, etc.).
- Community forums and websites (Stack Overflow).