Graphics Programs Reference
In-Depth Information
// item will be given a pointer to its container
[i setContainer:self];
}
- (BNRItem *)containedItem
{
return containedItem;
}
- (void)setContainer:(BNRItem *)i
{
container = i;
}
- (BNRItem *)container
{
return container;
}
In
main.m
, remove the code that populated the array with random items. Then create two
new items, add them to the array, and make them point at each other.
#import <Foundation/Foundation.h>
#import "BNRItem.h"
int main (int argc, const char * argv[])
{
@autoreleasepool {
NSMutableArray *items = [[NSMutableArray alloc] init];
for (int i = 0; i < 10; i++) {
BNRItem *p = [BNRItem randomItem];
[items addObject:p];
}
for (BNRItem *item in items)
NSLog(@"%@", item);
BNRItem *backpack = [[BNRItem alloc] init];
[backpack setItemName:@"Backpack"];
[items addObject:backpack];
BNRItem *calculator = [[BNRItem alloc] init];
[calculator setItemName:@"Calculator"];
[items addObject:calculator];
[backpack setContainedItem:calculator];
NSLog(@"Setting items to nil...");
items = nil;
}
return 0;
}
Here's what the application looks like now:
Figure 3.7 RandomPossessions with retain cycle
