Question

i’m having some troubles trying to parse an XML file and display the results grouped by an object property on a UITableView.
This is the XML file, I can change the structure if it’s necessary:

<Anuncios>
   <Anuncio id="1">
      <localeName>name1</localeName>
      <address>address1</address>
      <type>A</type>
   </Anuncio>
   <Anuncio id="2">
      <localeName>name2</localeName>
      <address>address2</address>
      <type>B</type>
   </Anuncio>
   <Anuncio id="3">
      <localeName>name3</localeName>
      <address>address3</address>
      <type>A</type>
   </Anuncio>
</Anuncios>

At this moment I have a NSMutableArray called servs containing objects (Anuncio).

This is the structure:

@interface Anuncio : NSObject

NSInteger iden;
NSString *localeName;
NSString *address;
NSString *type;

So, I would like to sort the UITableView by anuncio.type with the correct titleForHeaderInSection.

I downloaded the TableViewSuite from the Apple documentation, and the second example, SimpleSectionedTableView seems to do what I want, but instead of getting the data from an XML file, it gets the data calling [NSTimeZone knownTimeZoneNames], so the structure is quite different, I tried to adapt the sample code to my project, but i’m starting to realize that seems to be not the best way to do it. So I’m a bit stuck.

I was thinking on having arrays inside the main array containing the objects editing the XML, like that:

servs: {
         arrayA : { anuncio1, anuncio3 }
         arrayB : { anuncio2 }
}

but then I don’t know how to complete the tableView methods.

Here it is the XMLParse code:

- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName 
  namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName 
    attributes:(NSDictionary *)attributeDict {

    if([elementName isEqualToString:@"Anuncios"]) {
        //Initialize the array.
        appDelegate.servs = [[NSMutableArray alloc] init];
    }
    else if([elementName isEqualToString:@"Anuncio"]) {

        //Initialize the anuncio.
        serv = [[Anuncio alloc] init];

        //Extract the attribute here.
        serv.iden = [[attributeDict objectForKey:@"id"] integerValue];

        NSLog(@"Reading id value: %i", serv.iden);
    }
    NSLog(@"Processing Element: %@", elementName);
}

- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string { 

    if(!currentElementValue) 
        currentElementValue = [[NSMutableString alloc] initWithString:string];
    else
        [currentElementValue appendString:string];

    NSLog(@"Processing Value: %@", currentElementValue);

}

- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName 
  namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {

    if([elementName isEqualToString:@"Anuncios"])
        return;

    if([elementName isEqualToString:@"Anuncio"]) {
        [appDelegate.servs addObject:serv];

        [serv release];
        serv = nil;
    }
    else 
        [serv setValue:currentElementValue forKey:elementName];

    [currentElementValue release];
    currentElementValue = nil;
}

Part of my current UITableViewController:

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return [appDelegate.servs count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return 1;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
    anuncios = (NSMutableArray *)[appDelegate.servs sortedArrayUsingSelector:@selector(compare:)];
    Anuncio *anuncio = [anuncios objectAtIndex:section];
    return [anuncio type];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }
    anuncios = (NSMutableArray *)[appDelegate.servs sortedArrayUsingSelector:@selector(compare:)];
    Anuncio *anuncio = [anuncios objectAtIndex:indexPath.section];

    cell.textLabel.text = anuncio.localeName;
    cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;

    return cell;
}

At the moment I get:

A
--------
name1
--------
A
--------
name3
--------
B
--------
name2

and I would like to get:

A
--------
name1
name3
--------
B
--------
name2

I don’t know if the model that I’m proposing is the right one or i’m missing something. I thought it was something very common but I didn’t find anything about this.
Thanks for helping

Answer 1

In your Anuncio class, add a compare: method like this:

- (NSComparisonResult) compare:(Anuncio *)otherObject {
    return [self.type compare:otherObject.type];
}

Then sort your NSMutableArray with this:

anuncios = (NSMutableArray *)[anuncios sortedArrayUsingSelector:@selector(compare:)];