Save several ints to array and show total value in a label - iphone

Question

What I like to do:
User enters 10 in UITextField and tap on UIButton.
UILabel shows 10 and UITextField goes blank.
User enters 5 in UITextField and tap on UIButton.
UILable shows 15 and UITextField goes blank again.
With following code I get the entered number saved and shown in the label but how can I tell the array to add and show me total and not just the very first number I entered?
h
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController
#property (nonatomic, strong) IBOutlet UILabel *label;
#property (nonatomic, strong) IBOutlet UITextField *field;
#property (nonatomic, strong) NSString *dataFilePath;
#property (nonatomic, strong) NSString *docsDir;
#property (nonatomic, strong) NSArray *dirPaths;
#property (nonatomic, strong) NSFileManager *fileMgr;
#property (nonatomic, strong) NSMutableArray *array;
- (IBAction)saveNumber:(id)sender;
#end
m
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
#synthesize label, field, dataFilePath, docsDir, fileMgr, dirPaths, array;
- (void)viewDidLoad
{
[super viewDidLoad];
fileMgr = [NSFileManager defaultManager];
dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
docsDir = [dirPaths objectAtIndex:0];
dataFilePath = [[NSString alloc]initWithString:[docsDir stringByAppendingPathComponent:#"data.archive"]];
if ([fileMgr fileExistsAtPath:dataFilePath])
{
array = [NSKeyedUnarchiver unarchiveObjectWithFile:dataFilePath];
self.label.text = [array objectAtIndex:0];
}
else
{
array = [[NSMutableArray alloc] init];
}
}
- (IBAction)saveNumber:(id)sender
{
[array addObject:self.field.text];
[NSKeyedArchiver archiveRootObject:array toFile:dataFilePath];
[field setText:#""];
[label setText:[array objectAtIndex:0]];
}

Answer 1

You need to iterate through all the values and add them to a running total. Have a look at this:-
- (IBAction)saveNumber:(id)sender
{
[array addObject:self.field.text];
[NSKeyedArchiver archiveRootObject:array toFile:dataFilePath];
[field setText:#""];
// Create an enumerator from the array to easily iterate
NSEnumerator *e = [array objectEnumerator];
// Create a running total and temp string
int total = 0;
NSString stringNumber;
// Enumerate through all elements of the array
while (stringNumber = [e nextObject]) {
// Add current number to the running total
total += [stringNumber intValue];
}
// Now set the label to the total of all numbers
[label setText:[NSString stringWithFormat:#"%d",total];
}
I've commented the code for readability.

Answer 2

Iterate over the array, get all values as numbers using [string intValue] and sum them up in another variable. Then add the calculated value to the label using a formatted string like [NSString stringWithFormat: #"%d"].