Question

I have created two classes, one for StockHoldings, and the other Portfolio (an array). I created the values in main and am trying to add the created stock values into the portfolio, but when I do it I get “incompatible pointer types sending…”

This is what I have in main:

Portfolio *thisPortfolio = [[Portfolio alloc] init];

[thisPortfolio addPortfolioObject:[stockOne valueInDollars]];

Even if I just try and put an integer in place of [stockOne valueInDollars] which is a method of that calculates a stock’s value based off instance variables in stockholding, then I get “Implicit conversion of ‘int’ to ‘Portfolio’…”

This is what I have in the Portfolio.h file:

@interface Portfolio : NSObject
{
    NSMutableArray *myPortfolio;
}

- (void)addPortfolioObject:(Portfolio *)a;

And this is what I have in the Portolfio.m file:

- (void)addPortfolioObject:(Portfolio *)a
{
    // Is assets nil?
    if (!myPortfolio) {

        // Create the array
        myPortfolio = [[NSMutableArray alloc] init];

    }
    [myPortfolio addObject:a];
}

What am I doing wrong?

Answer 1

In the interface of Portfolio, indeed you declare the signature of addPortfolioObject such that a Portfolio object is expected, not an integer. The signature will have to change to (void)addPortfolioObject:(int)a both in the interface and the implemention. The latter will have to wrap a in an NSNumber using numberWithInt because NSArray can only store NSObjects while int instead is a base type.