CODEWITHSUNDEEP
objective-ccocoa
Axwack
Axwack

Reputation: 569

Property and Synthesize in Cocoa

I am trying to learn Cocoa and wanted to develop a very simple game that I had played in my youth. It was originally created in MS Basic. Please note I'm very new to Cocoa and objective c

I have create and object called Defaults. It stores three integer variables, planets, fighters and players.

On the front end, I have three drop down boxes with various defaulted values.

I wanted to understand KVC as well as how to set values but I get the following warning...

"Incompatible integer to pointer sending 'int' to parameter of type 'int *'

[NEW CODE]

DEFAULTS.H

#import #import 

@interface Defaults : NSObject {

int fighters;
int planets;
int players;

}

@property (assign) int fighters;
@property (assign) int planets;
@property (assign) int players;

@end

Here is an excerpt of the implementation in my controller:

#import "DefaultsController.h"
#import "Defaults.h"

@implementation DefaultsController

- (id)init
{
self = [super init];
if (self) {
    // Initialization code here
 Defaults *theDefaults = [[Defaults alloc] init];
    NSLog(@"Planets: %@",[theDefaults valueForKey:(@"planets")]);
}
return self;

}

-(void)dealloc
{ 
[super dealloc];
[Defaults release]; 
}

-(void) awakeFromNib{

}

-(IBAction) addPlanets:(id)sender{

[theDefaults setValue:[planetsButton titleOfSelectedItem] forKey:@"planets"];
[theDefaults setPlanets:[[planetsButton titleOfSelectedItem] intValue]];
theDefaults.planets = [[planetsButton titleOfSelectedItem] intValue];
NSLog(@"Planets: %i", theDefaults.planets);
NSLog(@"%@", [planetsButton titleOfSelectedItem]);
NSLog(@"%i", [[planetsButton titleOfSelectedItem] intValue]);

}

What am I doing wrong?

Upvotes: 0

Views: 615

Answers (1)

Seamus Campbell
Seamus Campbell

Reputation: 17916

You've declared your properties to be integer pointers, but then you're attempting to set them to integer values, not integer pointer values. Remove the asterisks in "int *fighters", etc, to change them to integers.

Pointers are one of the most fundamental and challenging concepts of C-based languages (including Objective-C), and if you aren't clear on the distinction I drew above I suggest you look for some careful explanations of how they work.

Update:

Another issue I see here, which may relate to your question below, is that you're doing some funny things with your logging statements. When you put %@ in a formatting string, you're telling NSLog that you want it to replace that with an Objective-C object. But an int is not an object; it's just a basic C type. Then, you're using key-value coding to retrieve your property value, which is further confusing the issue, because key-value coding is also intended to work with Objective-C objects. Replace that line with the following:

NSLog(@"Planets: %i", theDefaults.planets);

and I think you'll get something more in line with what you're expecting. %i tells NSLog that you have an integer value to print, and theDefaults.planets (or the equivalent [theDefaults planets]) will return the value of the planets property, whether it's an object or not.

Upvotes: 5

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