Objectice-C method, message, and Selector

Add a class method to the first Car method:

+ (NSString *) motto
{
return(@"Ford Prefects are Mostly Harmless");
}

 

# Import <UIKit/UIKit. h>
# Import "Car. h"

// Define the color and button style
# Define COOKBOOK_PURPLE_COLOR [UIColor colorWithRed: 0.20392f green: 0.19607f blue: 0.61176f alpha: 1.0f]
# Define BARBUTTON (TITLE, SELECTOR) [[[UIBarButtonItem alloc] initWithTitle: TITLE style: UIBarButtonItemStylePlain target: self action: SELECTOR] autorelease]

// Define the TestBedViewController
@ Interface TestBedViewController: UIViewController
@ End

// Implement the Controller
@ Implementation TestBedViewController
// Define a function
-(Void) action: (id) sender
{
// Calling a class method
NSLog (@ "% @", [Car motto]); // call a class function
}

-(Void) viewDidLoad
{
Self. navigationController. navigationBar. tintColor = COOKBOOK_PURPLE_COLOR;
Self. navigationItem. rightBarButtonItem = BARBUTTON (@ "Action", @ selector (action :)); // set the title and event of the button in the right navigation bar
// Here @ selector indicates the selector
}
@ End