Using custom method to add objects to NSMutableArray Objective C - objective-c

Question

I am new to Objective C, I'm trying to add objects to NSMutableArray that I can use multiple times on my project. I have a Model class as
History.h
import
#interface History : NSObject
#property (nonatomic) NSString *itemName;
#property (nonatomic) int quantity;
#property (nonatomic) double total;
#property (nonatomic) NSDate *purchaseDate;
- (instancetype)initWithName: (NSString*)itemName withQuantity:(int)quantity withTotal:(double) total withPurchaseDate:(NSDate*) purchaseDate;
#end
History.m
#import "History.h"
#implementation History
-(instancetype)initWithName: (NSString*)iName withQuantity:(int)iQuantity withTotal:(double) iTotal withPurchaseDate:(NSDate*) iPdate {
self = [super init];
if(self) {
self.itemName = iName;
self.quantity = iQuantity;
self.quantity = iQuantity;
self.purchaseDate = iPdate;
}
return self;
}
#end
Repository.h
#import <Foundation/Foundation.h>
#interface Repository : NSObject
#property (nonatomic) NSMutableArray *itemHistory;
-(void) pushToArray:(NSString *)name withQuantity:(int)qty withTotal:(double) total withPurchaseDate:(NSDate*) pDate;
#end
Repository.m
#import "Repository.h"
#import "History.h"
#interface Repository()
//#property (nonatomic) NSMutableArray *itemHistory;
#end
#implementation Repository
-(NSMutableArray *) itemHistory {
if(_itemHistory == nil) {
_itemHistory = [[NSMutableArray alloc] init];
}
return _itemHistory;
}
This is my method that I want to use to add objects to the MutableArray.
-(void) pushToArray:(NSString *)name withQuantity:(int)qty withTotal:(double) total withPurchaseDate:(NSDate*) pDate {
self.itemHistory = [[NSMutableArray alloc] init];
History *obj = [[History alloc] init];
obj.itemName = name;
obj.quantity = qty;
obj.total = total;
obj.purchaseDate = pDate;
[self.itemHistory addObject:obj];
}
#end
Thank you for your help in advance.

Answer 1

Every time you call pushToArray:... you are replacing the existing itemHistory with a new, empty, mutable array. You'll only ever see the last item to be pushed in that array.
However, you also don't need to lazily initialize _itemHistory. Just create an instance in your init method and be done with it. Saves confusion and refactoring hell.
In your Repository class, simply implement the designated initializer:
- (instancetype) init
{
if (self=[super init]) {
_itemHistory = [[NSMutableArray alloc] init];
}
return self;
}
Uncomment the property:
#interface Repository()
#property (nonatomic) NSMutableArray *itemHistory;
#end
And remove this from the -pushToArry:... method:
//self.itemHistory = [[NSMutableArray alloc] init];
If it still doesn't work, you need to show how you are logging the failure.