Question

I want to get the updates from a website based on the titles and links which is in xml format.

I have tried with the code below but it’s not working. In console it is showing the message:

2011-11-03 14:45:05.987 tabbar[673:e903] * Terminating app due to
uncaught exception ‘NSInvalidArgumentException’, reason: ‘-[NSCFString
isEqualtostring:]: unrecognized selector sent to instance 0x5746830’

If I run again, the table view is loading but there is no data in the table cells.

It is showing this message at the line if ([elementName isEqualtostring:@"item"]):

program received signal SIGABRT

-(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
    classelement = elementName;
    if ([elementName isEqualtostring:@"item"])
    {
        itemselected = YES;
        multitle = [[NSMutableString alloc]init];
        mullink = [[NSMutableString alloc]init];
    }
}

-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedname:(NSString *)qName
{
    if ([elementName isEqualToString:@"item"])
    {
        itemselected = NO;
        [titlearray addObject:multitle];
        [linkarray addObject:mullink];
        [multitle release];
        [mullink release];

        [self.tbl reloadData];
    }
}

-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
    if (itemselected)
    {
        if ([classelement isEqualToString:@"title"]) 
        {
            NSLog(@"%@",string);
            [multitle appendString:multitle];
        }
        else if([classelement isEqualToString:@"link"])
        {
            [multitle appendString:string];
        }
    }
}

Answer 1

Finally I got it. What I did is I have taken two NSMutableArrays and two NSMutableStrings and I appended the items to the strings, and later those strings I appended to the two arrays.

(void)viewDidLoad
{

    titlearray = [[NSMutableArray alloc]init];
    linkarray = [[NSMutableArray alloc]init];

    NSString *rssaddress =@"http://www.greenday.com/rss";
    NSURL *url = [NSURL URLWithString:rssaddress];
    xmlparser = [[NSXMLParser alloc]initWithContentsOfURL:url];
    [xmlparser setDelegate:self];
    [xmlparser parse];


    [super viewDidLoad];
}

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

    classelement = elementName;



    if([elementName isEqualToString:@"item" ])
    {
        itemselected = YES;
        titlestrng = [[NSMutableString alloc]init];
        linkstrng = [[NSMutableString alloc]init];

    }

}

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

    if([elementName isEqualToString:@"item" ])
    {
        itemselected = NO;
        [titlearray addObject:titlestrng];
        [linkarray addObject:linkstrng];


        [titlestrng release];
        [linkstrng release];


        [self.tb reloadData];
    }
}


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

    if(itemselected)
    {
        if([classelement isEqualToString:@"title"])
        {
            [titlestrng appendString: string];
                    NSLog(@"%@",titlestrng);
        }

        else if ([classelement isEqualToString:@"link"])
        {
            [linkstrng appendString:string];
            NSLog(@"%@",linkstrng);

        }
    }
}