property problems

[sumosumo84]

hi, i am new to properties and never knew their capabilities untill now.

Unfortunatly i cannot harness their capabilities as i am having an error.

Here is my code:

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
    [super viewDidLoad];
    ball = [Ball alloc];
    ball.position = CGPointMake(100.0, 100.0);
    ball.velocity = CGPointMake(4.0, 3.0);
    
}

(object ball was made in the .h)
(the errors are happening on ball.position, and ball.velocity.)

Ball.h:

@interface Ball : NSObject {
    CGPoint *position;
    CGPoint *velocity;
    CGFloat *radius;
    CGColorRef *color;
    
}

@property(nonatomic) CGPoint *position;
@property(nonatomic) CGPoint *velocity;
@property(nonatomic) CGFloat *radius;
@property(nonatomic) CGColorRef *color;

no errors here, but there is probably a problem causing the error.

The error is:

Assigning to 'CGPoint *' (aka 'struct CGPoint *') from incompatible type 'CGPoint' (aka 'struct CGPoint')

Looking at the error message, i am guessing it has something to do with having one CGPoint be a pointer, and the other not being a pointer. I am not for sure and don't want to screw anything up.

Thanks for your help!

-SumoSumo Apps

[Speed]

Try remove the asterisk from CGPoint *point; (ie. make it CGPoint point;

[sumosumo84]

Originally Posted by Speed

Try remove the asterisk from CGPoint *point; (ie. make it CGPoint point;

k ill try

[BrianSlick]

See the properties link in my signature for guidance.

Additionally:

ball = [Ball alloc];

1. This doesn't use the property
2. You can pretty much assume that alloc should always be followed by init

@interface Ball : NSObject {
    CGPoint *position;
    CGPoint *velocity;
    CGFloat *radius;
    CGColorRef *color;
}

@property(nonatomic) CGPoint *position;
@property(nonatomic) CGPoint *velocity;
@property(nonatomic) CGFloat *radius;
@property(nonatomic) CGColorRef *color;

There will be exceptions, but for the most part you can assume that * is used on objects, and is not used on non-objects (ints, floats, etc). None of these items are objects, so no *.

[sumosumo84]

it works, wow i feel stupid.
Thanks!