Chapter13~26:OC Basic -

#include vs. #import
A message send

class methods vs. instance methods
A message with an argument
a message send with three arguments

alloc and init

sending message to nil
id
memory management

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how to declare instance variable and instance methods
#import <> vs. #import ""
using custom classes
setter and getter
setter and getter naming conventions

using properties replace instance variables

#import <Foundation/Foundation.h>
#import "BNRPerson.h"

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // create an intance of BNRPerson
        BNRPerson *mikey = [[BNRPerson alloc]init];
        // give the instance variables interesting values using setters
        [mikey setHeightInMeters:1.8];
        [mikey setWeightInKilos:96];
        
        // log the instance variables using the getters
        float mikeyHeight = [mikey heightInMeters];
        int mikeyWeight = [mikey weightInKilos];
        NSLog(@"mikey is %.2f meters tall and weighs %d kilograms", mikeyHeight, mikeyWeight);
        

        // log some values using custom methods;
        float mikeyBMI = [mikey bodyMassIndex];
        NSLog(@"mikey has a BMI of %f", mikeyBMI);

        
    }
    return 0;
}

dot notation

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Another attribute that you will see shortly is copy. Practically speaking, whenever you declare a property that points to an NSString or an NSArray, you should include the copy attribute

override and super
inheritance hierarchy

hierarchy of BMI

description and %@
@class vs. import
class extensions
isEqual vs. identical


immutable objects
sort

define