Question

I am a little confused, and after countless attempts and read several articles I decided to write.
my problem is that if you call a method from a class (xml) and it is aimed at viewcontroller all goes well
but if I might add [self.view add…] it back to the top reloading the viewDidLoad of the viewController class entering into an endless loop.

this is what I do

class (ViewController)
.h

#import <UIKit/UIKit.h>

@class  XMLStuff;

@interface skiSpeedViewController : UIViewController {
}

@property (nonatomic, retain) XMLStuff *xml;

.m

- (void)viewDidLoad
{
    [super viewDidLoad];

    xml.skiSpeedC = self;

    GpsStuff *gps = [GpsStuff alloc];
    [gps init];
}

gps.m

- (id)init
{
    self = [super init];
    if (self) {
        xml = [XMLStuff alloc];
}
}
-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
     [xml lon:newLocation.coordinate.longitude lat:newLocation.coordinate.latitude];

xml.h

#import "skiSpeedViewController.h"

@class skiSpeedViewController;

@interface XMLStuff : NSObject <NSXMLParserDelegate> {
}

@property (retain, nonatomic) skiSpeedViewController *skiSpeedC;

.m

   @synthesize skiSpeedC;

- (void) parserDidEndDocument:(NSXMLParser *)parser {
NSLog(@"--%@", self.skiSpeedC); // Return (null)
[self.skiSpeedC riceviDic:datiMeteo];
}

ViewController.m

    -(void)riceviDic:(NSMutableDictionary *)dictMeteo {
        datiMeteo = [[NSMutableDictionary alloc]initWithDictionary:dictMeteo];
    }
}

Answer 1

- (void) parserDidEndDocument:(NSXMLParser *)parser {
    classViewController *skiSpeedC = [classViewController alloc];
    [skiSpeedC riceviDic:datiMeteo];
}

You are creating a new instance of classViewController every time. Your “xml” class (XMLStuff?) should have a pointer to the view controller and be calling the riceviDic method on that instance.

You’re getting an infinite loop because when you allocate the XML object in viewDidLoad, it too starts parsing the XML, then creates more XML objects, which then create more viewControllers…

So, add a property to XMLStuff of type classViewController, and when you create it in viewDidLoad:

xml.skiSpeedC = self;

Then, in parserDidEndDocument:

- (void) parserDidEndDocument:(NSXMLParser *)parser {
    [self.skiSpeedC riceviDic:datiMeteo];
}

UPDATE

OK, after your edit things look very different – you seem to have introduced a new class – GpsStuff, which has its own instance of XMLStuff (and a dodgy looking init method which I assume you haven’t copied in properly?). Which one is actually parsing your document? XMLStuff in your view controller, or in GPSStufF? I’m guessing the one in GPSStuff, which you haven’t set the skiSpeedC property for. I was previously assuming that you were calling everything from your view controller.

Why not remove the creation of a new XMLStuff object from GPSStuff, and when you create GPSStuff in your view controller, pass the xml object you’ve created into it:

- (void)viewDidLoad
{
    [super viewDidLoad];

    GpsStuff *gps = [[GpsStuff alloc] init];
    XMLStuff *xml = [[XMLStuff alloc] init];
    xml.skiSpeedC = self;
    gps.xml = xml;
    [xml release];
}

Also, the skiSpeedC property should probably not be retain, since it is essentially a delegate assignment and the view controller is not going to be released before you release the xml parser.

As a note, by convention you should be initializing objects like this:

GPSStuff *gps = [[GPSStuff alloc] init];

Not on two lines. You want what is returned from init to be assigned to your variable.