How to parse XML to iPhone correctly - iphone

Question

I have an XML file, but do not know what I have done wrong as the app crashed, I do not know how to solve it. Can anyone help giving me some comments.
<list>
<section name="Texts">
<item>
<postID>26</postID>
<title>A sample quiz</title>
<url>http://yahoo.com</url>
<score>20</score>
</item>
<item>
<postID>230</postID>
<title>A sample quiz</title>
<url>http://www.yahoo.com</url>
<score>20</score>
</item>
</section>
<section name="Images">
<item>
<postID>27</postID>
<title>A sample image quiz</title>
<url>www.google.com</url>
<score>10</score>
</item>
<item>
<postID>27</postID>
<title>A sample image quiz</title>
<url>www.google.com</url>
<score>10</score>
</item>
</section>
</list>
Code I have used:
-(allChallengeParser *)initXMLParser
{
self = [super init];
appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
appDelegate.allChallengeArray = [[NSMutableArray alloc]init];
xmlChallengeRoot =[[NSMutableArray alloc]init];
return self;
}
-(void)parser:(NSXMLParser *)parser
didStartElement:(NSString *)elementName
namespaceURI:(NSString *)namespaceURI
qualifiedName:(NSString *)qName
attributes:(NSDictionary *)attributeDict {
//Implement method called NSXMLParser when it hits the start of an element:
if([elementName isEqualToString:#"list"])
{
NSLog(#"list root element found – create a new instance of challenge OBj...");
allChallengeObj = [[allChallenge alloc] init];
//We do not have any attributes in the user elements, but if
// if have can extract them here:
// user.att = [[attributeDict objectForKey:#"<att name>"] ...];
}
else if([elementName isEqualToString:#"section"])
{
allChallengeObj = [[allChallenge alloc] init];
allChallengeObj.section = [attributeDict valueForKey:#"name"];
NSLog(#"allChallengeObj.section %#", allChallengeObj.section);
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
if(!currentElementValue)
// init the ad hoc string with the value
currentElementValue = [[NSMutableString alloc] initWithString:string];
else
// append value to the ad hoc string
[currentElementValue appendString:string];
NSLog(#"Processing Value for: %#", currentElementValue);
}
- (void)parser:(NSXMLParser *)parser
didEndElement:(NSString *)elementName
namespaceURI:(NSString *)namespaceURI
qualifiedName:(NSString *)qName {
if ([elementName isEqualToString:#"list"]) {
return;
}
if ([elementName isEqualToString:#"section"]) {
// We are done with user entry – add the parsed user
// object to our user array
[xmlChallengeRoot addObject:allChallengeObj];
// release user object
allChallengeObj = nil;
}
else
{
// The parser hit one of the element values.
// This syntax is possible because User object
// property names match the XML user element names
NSLog(#"elementName %#",elementName);
NSLog(#"current Element Value %#",currentElementValue);
[allChallengeObj setValue:currentElementValue forKey:elementName];
}
currentElementValue = nil;
}

Answer 1

Could you give us error message?
For parsing on iPhone you can use external libraries. Here are some test related to them http://www.raywenderlich.com/553/how-to-chose-the-best-xml-parser-for-your-iphone-project NSXMLParser is really simple event parser.