Objective C: Returns an array of objects from a class method

Question

I did an honest search and did not find the answer to my question, so I was hoping that someone could point me in the right direction

I am new to Objective-C, and I have a little problem when I do something that I imagine is pretty simple; returns an NSArray of objects from a class method

I have the following class with an associated class method

@implementation Sale @synthesize title = _title; @synthesize description = _description; @synthesize date = _date; +(NSArray*)liveSales { NSArray *liveSales = [[NSArray alloc] init]; for(int i = 0; i < 100; i++) { Sale *s = [[Sale alloc] init]; [s setTitle:[NSString stringWithFormat:@"Sale %d", i+1]]; [s setDescription:[NSString stringWithFormat:@"Sale %d descriptive text", i+1]]; [liveSales addObject:s]; [s release]; s = nil; } return [liveSales autorelease]; } @end 

And I have a ViewController with the following code (cropped for readability):

 @implementation RootViewController @synthesize saleList = _saleList; - (void)viewDidLoad { [super viewDidLoad]; // Uncomment the following line to display an Edit button in the navigation bar for this view controller. // self.navigationItem.rightBarButtonItem = self.editButtonItem; [[self saleList] setArray:[Sale liveSales]]; } 

The problem I ran into is that the count of saleList is always zero, so it seems that the array is not set. If I debug the code and am in the method of the liveSales class, that is, the correct number of objects in the array at the return point

Can someone point me in the right direction?

Thanks:)

Dave

Answer 1

Perhaps because saleList is nil . Sending a nil message in Objective-C (in most cases) does nothing.

Try this instead:

 self.saleList = [Sale liveSales]; 

(assuming the property is declared as persistence).

Answer 2

First of all, you should highlight NSMutableArray :

 NSMutableArray *liveSales = [[NSMutableArray alloc] init]; 

A simple NSArray by definition, immutable.