Editing And Updating Stored Data in NSUserdefaults

//second view controller

-(void)edit:(id)sender{

    

    UIButton *tappedButton = (UIButton*)sender;

    q=tappedButton.tag;

    NSString *index=[NSString stringWithFormat:@"%d",q];

    [currentDefaults setObject:index forKey:@"edit"];

    [self.navigationController popViewControllerAnimated:YES];

    

}

// main ViewController

- (void)viewWillAppear:(BOOL)animated {

    

    [super viewWillAppear:animated];

    

    NSData *dataRepresentingSavedArray0 = [currentDefaults objectForKey:@"name"];

    NSMutableArray *oldSavedArray0 = [NSKeyedUnarchiver unarchiveObjectWithData:dataRepresentingSavedArray0];

    nameArray = [[NSMutableArray alloc] initWithArray:oldSavedArray0];

    

    NSData *dataRepresentingSavedArray1 = [currentDefaults objectForKey:@"place"];

    NSMutableArray *oldSavedArray1 = [NSKeyedUnarchiver unarchiveObjectWithData:dataRepresentingSavedArray1];

    placeArray = [[NSMutableArray alloc] initWithArray:oldSavedArray1];

    

    //if Editing Needs to be done on Stored Data

    

    if([currentDefaults objectForKey:@"edit"]){

        NSString *index=[currentDefaults valueForKey:@"edit"];

        p=[index intValue];

        

        myTextField1.text=[nameArray objectAtIndex:p];

        myTextField2.text=[placeArray objectAtIndex:p];

        

    }

}

- (IBAction)savedata:(id)sender{

    

    if([currentDefaults objectForKey:@"edit"]){

       

        [nameArray replaceObjectAtIndex:p withObject:myTextField1.text];

        [placeArray replaceObjectAtIndex:p withObject:myTextField2.text];

    }else{

    

    [nameArray addObject:myTextField1.text];

    [placeArray addObject:myTextField2.text];

    }

    

    [currentDefaults setObject:[NSKeyedArchiver archivedDataWithRootObject:nameArray] forKey:@"name"];

    [currentDefaults setObject:[NSKeyedArchiver archivedDataWithRootObject:placeArray] forKey:@"place"];

    myTextField1.text=@"";

    myTextField2.text=@"";

}

- (IBAction)listData:(id)sender{

    listView *anotherViewController = [[listView alloc] initWithNibName:@"listView" bundle:nil];

    

    [self.navigationController pushViewController:anotherViewController animated:YES];

    [[NSUserDefaults standardUserDefaults]removeObjectForKey:@"edit"];

    myTextField1.text=@"";

    myTextField2.text=@"";

}