Graphics Programs Reference
In-Depth Information
Click on
main.m
to open it in the editor area, and you'll see that some code has been
written for you - most notably, a
main
function that is the entry point of any C or
Objective-C application.
Time to put your knowledge of Objective-C basics to the test. Delete the line of code that
NSLog
s “Hello, World!” and replace it with lines that create and destroy an instance of
the Objective-C class
NSMutableArray
.
#import <Foundation/Foundation.h>
int main (int argc, const char * argv[])
{
@autoreleasepool {
// insert code here...
NSLog(@"Hello, World!");
// Create a mutable array object, store its address in items variable
NSMutableArray *items = [[NSMutableArray alloc] init];
// Destroy the array pointed to by items
items = nil;
}
return 0;
}
Once you have an instance of
NSMutableArray
, you can send it messages, like
ad-
dObject:
and
insertObject:atIndex:
. In this code, the receiver is the
items
variable that points at the newly instantiated
NSMutableArray
. Add a few strings to
the array instance.
int main (int argc, const char * argv[])
{
@autoreleasepool {
// Create a mutable array object, store its address in items variable
NSMutableArray *items = [[NSMutableArray alloc] init];
