Help me out Strange issue when parsing - iphone

I am having a strange problem when using this XML-to-NSDictionary class.really it was working great.
suddenly we found one weired problem using this.Let me explain this...when i have only one item the app is crashing. but when i have more than one item the app is not crashing.
When i have only one item to parse , after parsing if i print the count it shows as 6
But when i have more than one item, after parsing when i print the count it shows correctly
**
crash log:-
-[NSCFString objectAtIndex:]: unrecognized selector sent to instance
0x5c9a040 Terminating app due to
uncaught exception
'NSInvalidArgumentException', reason:
'-[NSCFString objectAtIndex:]:
unrecognized selector sent to instance
0x5c9a040'
**
Please help me out and thanks for your time
Source code
-(void)RequestUpdate
{
NSDictionary *mailDict = [[XMLReader dictionaryForXMLString:responseXML error:nil]
valueForKeyPath:#"response.mails.mail"];
NSLog(#"MAILS>MAIL COUNT %d %#", [mailDict count], mailDict);
}
#import "XMLReader.h"
NSString *const kXMLReaderTextNodeKey = #"text";
#interface XMLReader (Internal)
- (id)initWithError:(NSError **)error;
- (NSDictionary *)objectWithData:(NSData *)data;
#end
#implementation XMLReader
#pragma mark -
#pragma mark Public methods
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)error
{
XMLReader *reader = [[XMLReader alloc] initWithError:error];
NSDictionary *rootDictionary = [reader objectWithData:data];
[reader release];
return rootDictionary;
}
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)error
{
NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
return [XMLReader dictionaryForXMLData:data error:error];
}
#pragma mark -
#pragma mark Parsing
- (id)initWithError:(NSError **)error
{
if ((self = [super init]))
{
errorPointer = error;
}
return self;
}
- (void)dealloc
{
[dictionaryStack release];
[textInProgress release];
[super dealloc];
}
- (NSDictionary *)objectWithData:(NSData *)data
{
// Clear out any old data
[dictionaryStack release];
[textInProgress release];
dictionaryStack = [[NSMutableArray alloc] init];
textInProgress = [[NSMutableString alloc] init];
// Initialize the stack with a fresh dictionary
[dictionaryStack addObject:[NSMutableDictionary dictionary]];
// Parse the XML
NSXMLParser *parser = [[[NSXMLParser alloc] initWithData:data] autorelease];
parser.delegate = self;
BOOL success = [parser parse];
// Return the stack's root dictionary on success
if (success)
{
NSDictionary *resultDict = [dictionaryStack objectAtIndex:0];
return resultDict;
}
return nil;
}
#pragma mark -
#pragma mark NSXMLParserDelegate methods
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
// Get the dictionary for the current level in the stack
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
// Create the child dictionary for the new element, and initilaize it with the attributes
NSMutableDictionary *childDict = [NSMutableDictionary dictionary];
[childDict addEntriesFromDictionary:attributeDict];
// If there's already an item for this key, it means we need to create an array
id existingValue = [parentDict objectForKey:elementName];
if (existingValue)
{
NSMutableArray *array = nil;
if ([existingValue isKindOfClass:[NSMutableArray class]])
{
// The array exists, so use it
array = (NSMutableArray *) existingValue;
}
else
{
// Create an array if it doesn't exist
array = [NSMutableArray array];
[array addObject:existingValue];
// Replace the child dictionary with an array of children dictionaries
[parentDict setObject:array forKey:elementName];
}
// Add the new child dictionary to the array
[array addObject:childDict];
}
else
{
// No existing value, so update the dictionary
[parentDict setObject:childDict forKey:elementName];
}
// Update the stack
[dictionaryStack addObject:childDict];
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
// Update the parent dict with text info
NSMutableDictionary *dictInProgress = [dictionaryStack lastObject];
// Set the text property
if ([textInProgress length] > 0)
{
[dictInProgress setObject:textInProgress forKey:kXMLReaderTextNodeKey];
// Reset the text
[textInProgress release];
textInProgress = [[NSMutableString alloc] init];
}
// Pop the current dict
[dictionaryStack removeLastObject];
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
// Build the text value
[textInProgress appendString:string];
}
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError
{
// Set the error pointer to the parser's error object
*errorPointer = parseError;
}
#end
Sample XML Data
<response>
<mails>
<mail id="4e12a3b04ff5ae0774000082">
<created_on>2011-07-05T05:40:00+00:00</created_on>
<updated_on>2011-07-05T05:40:00+00:00</updated_on>
<creator id="4e0abdff54b53058ff0000a2"><name>Merk Warn</name></creator>
<text>eee</text>
</mail>
<mail id="4e12dcvxva3b04ff5ae0774000082">
<created_on>2011-07-05T05:40:00+00:00</created_on>
<updated_on>2011-07-05T05:40:00+00:00</updated_on>
<creator id="4e0abdff54b53058ff0000a2"><name>Merk Warn</name></creator>
<text>eee</text>
</mail>
</mails>
</response>

That's because the tag is stored directly as an NSDictionary object if there is only one element. The count you are getting is the number of key-value pairs in a dictionary.
You can handle this differently,
-(void)update
{
id value = [[XMLReader dictionaryForXMLString:responseXML error:nil] valueForKeyPath:#"response.mails.mail"];
NSArray * mails;
if ( [value isKindOfClass:[NSDictionary class]] ) {
mails = [NSArray arrayWithObject:value];
}
else {
mails = (NSArray *)value;
}
/* `mails` is an array of <mail> based dictionaries */
}
You will have to retain it appropriately.

Related

how read all the child elements of xml using Xcode?

I need to read all child nodes dynamically from node 'book' with id 1 (if you add a child node in xml file but not have to change anything in the code) and put the values ​​of the child nodes into a tableView.
As I can I do?
<Book id="1">
<name>Vishal</name>
<address>Mumbai</address>
<country>India</country>
<editorial>Trillas</editorial>
<edicion>Segunda</edicion>
</Book>
<Book id="2">
<name>Vinod</name>
<address>Delhi</address>
<autor>Julianne MacLean</autor>
</Book>
<Book id="3">
<name>Sachin</name>
<address>pune</address>
<country>India</country>
<editorial>Porrua</editorial>
</Book>
<Book id="4">
<name>Nilesh</name>
<address>Nasik</address>
<country>India</country>
</Book>
<Book id="5">
<name>Video</name>
<address>Nasik</address>
<country>India</country>
</Book>
You Can yoe XMLReader (parser)
XMLReader.h
#import <Foundation/Foundation.h>
#interface XMLReader : NSObject<NSXMLParserDelegate>
{
NSMutableArray *dictionaryStack;
NSMutableString *textInProgress;
NSError __strong **_errorPointer;
}
+ (id)parseXML:(NSString *)file_name;
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)errorPointer;
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)errorPointer;
#end
XMLReader.m
#import "XMLReader.h"
NSString *const kXMLReaderTextNodeKey = #"element_text";
#interface XMLReader (Internal)
- (id)initWithError:(NSError **)error;
- (NSDictionary *)objectWithData:(NSData *)data;
#end
#implementation XMLReader
#pragma mark -
#pragma mark Public methods
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)error
{
XMLReader *reader = [[XMLReader alloc] initWithError:error];
NSDictionary *rootDictionary = [reader objectWithData:data];
[reader release];
return rootDictionary;
}
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)error
{
NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
return [XMLReader dictionaryForXMLData:data error:error];
}
#pragma mark -
#pragma mark Parsing
- (id)initWithError:(NSError **)error
{
if (self = [super init])
{
_errorPointer = error;
}
return self;
}
- (void)dealloc
{
[dictionaryStack release];
[textInProgress release];
[super dealloc];
}
- (NSDictionary *)objectWithData:(NSData *)data
{
// Clear out any old data
[dictionaryStack release];
[textInProgress release];
dictionaryStack = [[NSMutableArray alloc] init];
textInProgress = [[NSMutableString alloc] init];
// Initialize the stack with a fresh dictionary
[dictionaryStack addObject:[NSMutableDictionary dictionary]];
// Parse the XML
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:data];
parser.delegate = self;
BOOL success = [parser parse];
// Return the stack's root dictionary on success
if (success)
{
NSDictionary *resultDict = [dictionaryStack objectAtIndex:0];
return resultDict;
}
return nil;
}
#pragma mark -
#pragma mark NSXMLParserDelegate methods
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
// Get the dictionary for the current level in the stack
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
// Create the child dictionary for the new element, and initilaize it with the attributes
NSMutableDictionary *childDict = [NSMutableDictionary dictionary];
[childDict addEntriesFromDictionary:attributeDict];
// If there's already an item for this key, it means we need to create an array
id existingValue = [parentDict objectForKey:elementName];
if (existingValue)
{
NSMutableArray *array = nil;
if ([existingValue isKindOfClass:[NSMutableArray class]])
{
// The array exists, so use it
array = (NSMutableArray *) existingValue;
}
else
{
// Create an array if it doesn't exist
array = [NSMutableArray array];
[array addObject:existingValue];
// Replace the child dictionary with an array of children dictionaries
[parentDict setObject:array forKey:elementName];
}
// Add the new child dictionary to the array
[array addObject:childDict];
}
else
{
// No existing value, so update the dictionary
[parentDict setObject:childDict forKey:elementName];
}
// Update the stack
[dictionaryStack addObject:childDict];
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
// Update the parent dict with text info
NSMutableDictionary *dictInProgress = [dictionaryStack lastObject];
// Set the text property
if ([textInProgress length] > 0)
{
[dictInProgress setObject:textInProgress forKey:kXMLReaderTextNodeKey];
// Reset the text
[textInProgress release];
textInProgress = [[NSMutableString alloc] init];
}
// Pop the current dict
[dictionaryStack removeLastObject];
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
string = [string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
// Build the text value
[textInProgress appendString:string];
}
+ (id)parseXML:(NSString *)file_name{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *documentFolderPath = [paths objectAtIndex: 0];
NSString *filePath = [documentFolderPath stringByAppendingPathComponent:appDelegate.path];
if ([file_name isEqualToString:#"yourXMLfilename.xml"])
filePath = [filePath stringByDeletingLastPathComponent];
filePath = [filePath stringByAppendingPathComponent:file_name];
NSString* theContents = [[NSString alloc] initWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:nil];
NSDictionary* dict = [self dictionaryForXMLString:theContents error:nil];
//This dictionary contains your tags of one record.
// you can get yor tag value by
NSString *val = #"";
if ([[dict allKeys] containsObject:#"name"]) {
val = [dict objectForKey:#"name"];
}
}
#end

Memory Leak & App Crash when going back to Album List

I'm using three20 to create image viewer. First i'm creating list of albums from the sql db and when user selects any album, its url string is passed to the this code that creates thums of available pics on network using XML Parser. everything works fine but when user goes back to the album list and selects another album. app crashes with 'Thread 1: Program received singal: "EXC+BAD_ACCESS" in main.m. plus XCode Product Analyze gives potential memory leak where i'm creating photoSource in the viewDidLoad. Here is the code
#import "AlbumController.h"
#import "PhotoSource.h"
#import "Photo.h"
#import "AlbumInfo.h"
#import "AlbumDatabase.h"
#implementation AlbumController
#synthesize albumName;
#synthesize urlAddress;
#synthesize images;
- (void)viewDidLoad
{
[super viewDidLoad];
// NSLog(#"%#", self.urlAddress);
[self createPhotos]; // method to set up the photos array
self.photoSource = [[PhotoSource alloc]
initWithType:PhotoSourceNormal
title:self.albumName
photos:images
photos2:nil];
self.navigationController.navigationBar.tintColor = [UIColor blackColor];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// release and set to nil
}
-(void)createPhotos
{
if ([stories count] == 0)
{
NSString *path = self.urlAddress;
[self parseXMLFileAtURL:path];
}
images = [NSMutableArray arrayWithCapacity:[stories count]]; // needs to be mutable
for (int i = 0; i < [stories count]; i++)
{
NSString *img = [[stories objectAtIndex:i] objectForKey:#"image"];
img = [img stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];
//NSString * caption = [[stories objectAtIndex:i] objectForKey:#"caption"];
//caption = [caption stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];
[images addObject:[[[Photo alloc] initWithURL:img smallURL:img size:CGSizeMake(320, 212)] autorelease]];
}
}
#pragma mark -
#pragma mark XML Parser Implementation
- (void)parserDidStartDocument:(NSXMLParser *)parser{
//NSLog(#"found file and started parsing");
}
- (void)parseXMLFileAtURL:(NSString *)URL
{
stories = [[NSMutableArray alloc] init];
//you must then convert the path to a proper NSURL or it won't work
NSURL *xmlURL = [NSURL URLWithString:URL];
// here, for some reason you have to use NSClassFromString when trying to alloc NSXMLParser, otherwise you will get an object not found error
// this may be necessary only for the toolchain
rssParser = [[NSXMLParser alloc] initWithContentsOfURL:xmlURL];
// Set self as the delegate of the parser so that it will receive the parser delegate methods callbacks.
[rssParser setDelegate:self];
// Depending on the XML document you're parsing, you may want to enable these features of NSXMLParser.
[rssParser setShouldProcessNamespaces:NO];
[rssParser setShouldReportNamespacePrefixes:NO];
[rssParser setShouldResolveExternalEntities:NO];
[rssParser parse];
}
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError {
NSString * errorString = [NSString stringWithFormat:#"Unfortunately it is not possible to load Pictures. Please check Internet Connection. (Error code %i )", [parseError code]];
//NSLog(#"error parsing XML: %#", errorString);
UIAlertView * errorAlert = [[UIAlertView alloc] initWithTitle:#"Failed to load the feed." message:errorString delegate:self cancelButtonTitle:#"OK" otherButtonTitles:nil];
[errorAlert show];
[errorAlert release];
}
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
//NSLog(#"found this element: %#", elementName);
currentElement = [elementName copy];
if ([elementName isEqualToString:#"item"]) {
// clear out our story item caches...
item = [[NSMutableDictionary alloc] init];
currentCaption = [[NSMutableString alloc] init];
//currentThumbnail = [[NSMutableString alloc] init];
currentImage = [[NSMutableString alloc] init];
}
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName{
//NSLog(#"ended element: %#", elementName);
if ([elementName isEqualToString:#"item"]) {
// save values to an item, then store that item into the array...
//[item setObject:currentThumbnail forKey:#"thumbnail"];
//[item setObject:currentCaption forKey:#"caption"];
[item setObject:currentImage forKey:#"image"];
[stories addObject:[[item copy] autorelease]];
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string{
// save the characters for the current item...
if ([currentElement isEqualToString:#"thumbnail"]) {
//[currentThumbnail appendString:string];
}// else if ([currentElement isEqualToString:#"caption"]) {
//[currentCaption appendString:string];
//}
else if ([currentElement isEqualToString:#"image"]) {
[currentImage appendString:string];
}
}
- (void)parserDidEndDocument:(NSXMLParser *)parser {
NSLog(#"all done!");
NSLog(#"stories array has %d items", [stories count]);
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
{
if (toInterfaceOrientation == UIInterfaceOrientationPortrait ||
toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft ||
toInterfaceOrientation == UIInterfaceOrientationLandscapeRight)
{
return YES;
}
else
{
return NO;
}
}
#pragma mark -
#pragma mark Memory Management
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning]; // Releases the view if it doesn't have a superview
// Release anything that's not essential, such as cached data
}
- (void)dealloc {
[currentElement release];
[rssParser release];
[stories release];
[item release];
[currentCaption release];
//[currentThumbnail release];
[currentImage release];
[images release];
[stories release];
[super dealloc];
}
#end
and here is the didSelectRowAtIndexPath thats pushing this view
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
AlbumInfo *info = [_albumInfos objectAtIndex:indexPath.row];
AlbumController *albumController = [[AlbumController alloc] init];
albumController.urlAddress = info.address;
albumController.albumName = info.name;
[self.navigationController pushViewController:albumController animated:YES];
[albumController release];
}
Here is the code for AlbumController.h
#import <Foundation/Foundation.h>
#import "Three20/Three20.h"
#interface AlbumController : TTThumbsViewController <NSXMLParserDelegate>
{
NSString *albumName;
NSString *urlAddress;
// images
NSMutableArray *images;
// parser
NSXMLParser * rssParser;
NSMutableArray * stories;
NSMutableDictionary * item;
NSString * currentElement;
NSMutableString * currentImage;
NSMutableString * currentCaption;
}
#property (nonatomic, strong) NSString *albumName;
#property (nonatomic, strong) NSString *urlAddress;
#property (nonatomic, retain) NSMutableArray *images;
- (void)createPhotos;
- (void)parseXMLFileAtURL:(NSString *)URL;
#end
used this tutorial http://www.raywenderlich.com/1430/how-to-use-the-three20-photo-viewer
Need help solving this memory leak and need to know why its crashing.
Thanks
Simple. In Xcode 4.0+, Just click-hold on the Run icon, and press Profile. It'll open up Instruments, and you'll want Zombies. Then navigate your app to where the crash happened before, and this time, it'll show up in Instruments with the caller, and all the information about it.
The memory leak in viewDidLoad is caused by the following line:
self.photoSource = [[PhotoSource alloc]
initWithType:PhotoSourceNormal
title:self.albumName
photos:images
photos2:nil];
[PhotoSource alloc] returns an object you own (with a retain count of +1).
initWithType:title:photos:photos2: does not change the retain count.
So viewDidLoad is left with an object it owns, but no pointer to it. To balance the alloc you should send an autorelease message:
self.photoSource = [[[PhotoSource alloc]
initWithType:PhotoSourceNormal
title:self.albumName
photos:images
photos2:nil] autorelease];

nsxml parser issue

I am quite fine with iPhone and have done this before but can't figure it out right now.
I am using the XMLParser and getting a response as shown below:
username = {
text = akhildas;
type = string;
};
Instead what I expect is
username = akhildas
What I have already done is:
- (NSDictionary *)objectWithData:(NSData *)data
{
// Clear out any old data
[dictionaryStack release];
[textInProgress release];
dictionaryStack = [[NSMutableArray alloc] init];
textInProgress = [[NSMutableString alloc] init];
// Initialize the stack with a fresh dictionary
[dictionaryStack addObject:[NSMutableDictionary dictionary]];
// Parse the XML
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:data];
parser.delegate = self;
BOOL success = [parser parse];
// Return the stack's root dictionary on success
if (success)
{
NSDictionary *resultDict = [dictionaryStack objectAtIndex:0];
return resultDict;
}
return nil;
}
#pragma mark -
#pragma mark NSXMLParserDelegate methods
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
// Get the dictionary for the current level in the stack
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
// Create the child dictionary for the new element, and initilaize it with the attributes
NSMutableDictionary *childDict = [NSMutableDictionary dictionary];
[childDict addEntriesFromDictionary:attributeDict];
// If there's already an item for this key, it means we need to create an array
id existingValue = [parentDict objectForKey:elementName];
if (existingValue)
{
NSMutableArray *array = nil;
if ([existingValue isKindOfClass:[NSMutableArray class]])
{
// The array exists, so use it
array = (NSMutableArray *) existingValue;
}
else
{
// Create an array if it doesn't exist
array = [NSMutableArray array];
[array addObject:existingValue];
// Replace the child dictionary with an array of children dictionaries
[parentDict setObject:array forKey:elementName];
}
// Add the new child dictionary to the array
[array addObject:childDict];
}
else
{
// No existing value, so update the dictionary
[parentDict setObject:childDict forKey:elementName];
}
// Update the stack
[dictionaryStack addObject:childDict];
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
// Update the parent dict with text info
NSMutableDictionary *dictInProgress = [dictionaryStack lastObject];
// Set the text property
if ([textInProgress length] > 0)
{
[dictInProgress setObject:textInProgress forKey:kXMLReaderTextNodeKey];
// Reset the text
[textInProgress release];
textInProgress = [[NSMutableString alloc] init];
}
// Pop the current dict
[dictionaryStack removeLastObject];
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
// Build the text value
[textInProgress appendString:string];
}
Any one had same problem and solved it well?
I always try to avoid callback based (SAX) NSXMLParser in favor of DOM parsers which creates DOM tree model for you. I find DOM parsers so much easier to cope with.
My favorite is GDataXML parser (developed by Google). It is very reliable and easy to use. It consists of 2 files only (and libxml2 library) but is very powerful.
It saves you from looking up your delegates methods and wondering if you followed your XML structure correctly and extracted your object in proper way.
Mapping XML document to the Objective-C objects tree can be done as short as below:
NSData *xmlData = [[NSMutableData alloc] initWithContentsOfFile:filePath];
NSError *error;
GDataXMLDocument *doc = [[GDataXMLDocument alloc] initWithData:xmlData
options:0 error:&error];
if (doc != nil)NSLog(#"%#", doc.rootElement);
See this very popular tutorial on XML parsing for iPhone where GDataXML is explained:
http://www.raywenderlich.com/725/how-to-read-and-write-xml-documents-with-gdataxml
Hope it will make your life easier with tracking and parsing XML data.

XML Parsing in iPhone

I am new in xml parsing.I am totaly cofused how many methods we should have to require for xml parsing and what does use of that method.I want to send input to the webservied and by use of xml parsing i want to display result in my text field.
See this questions for resources on how to pick an XML parser for your iOS application:
Choosing the right IOS XML parser
I choose TouchXML for my projects. It is a DOM parser and has XPath support:
https://github.com/TouchCode/TouchXML
You should use the following methods:
- (void)parseXMLFileAtURL:(NSString *)URL { //own method from me, URL could be local file or internet website
itemsOfFeed = [[NSMutableArray alloc] init];
NSURL *xmlURL = [NSURL URLWithString:URL];
feedParser = [[NSXMLParser alloc] initWithContentsOfURL:xmlURL];
[feedParser setDelegate:self];
[feedParser setShouldProcessNamespaces:NO];
[feedParser setShouldReportNamespacePrefixes:NO];
[feedParser setShouldResolveExternalEntities:NO];
[feedParser parse];
}
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError {
//in case of an error
}
- (void)parserDidStartDocument:(NSXMLParser *)parser {
// start to parse xml
}
-(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict {
feedElement = [elementName copy];
if([elementName isEqualToString:#"item"]) { //main xml tag
item = [[NSMutableDictionary alloc] init];
feedTitle = [[NSMutableString alloc] init];
feedDate = [[NSMutableString alloc] init];
feedText = [[NSMutableString alloc] init];
feedLink = [[NSMutableString alloc] init];
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
if([feedElement isEqualToString:#"title"]) {
[feedTitle appendString:string];
} else if([feedElement isEqualToString:#"link"]) { // some examples of tags
[feedLink appendString:string];
} else if([feedElement isEqualToString:#"content:encoded"]) {
[feedText appendString:string];
} else if([feedElement isEqualToString:#"pubDate"]) {
[feedDate appendString:string];
}
}
- (void) parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
if([elementName isEqualToString:#"item"]) {
[item setObject:feedTitle forKey:#"title"];
[item setObject:feedDate forKey:#"date"];
[item setObject:feedText forKey:#"text"];
[item setObject:feedLink forKey:#"link"];
[itemsOfFeed addObject:item];
}
}
- (void)parserDidEndDocument:(NSXMLParser *)parser {
[self.myTableView reloadData]; // for example reload table view
[self writeArrayToFile]; //or write to a local property list
}
in your header file:
NSMutableArray *itemsOfFeed;
NSXMLParser *feedParser;
NSMutableDictionary *item;
NSMutableString *feedElement;
NSMutableString *feedTitle, feedDate, feedText, feedLink; //strings of your tags
Then you have:
NSArray
NSDictionary
object a
object b
object c
Just access 'object a' and put it in your text field
hopefully this code example helps you
Here is the very helpful tutorial.
http://www.edumobile.org/iphone/iphone-programming-tutorials/parsing-an-xml-file/
Hi I would personally prefer to use NSXMLParser.
Write your own code which uses NSXMLParserDelegate methods implementation.
But still there are some third party libraries available. Here is a nice example to compare how all those parser differs from each other and also having nice explanation. Code is also available over there.
Hope this will be helpful to you.
-Mrunal
i have a demo app for parsing static XML to UITableView, I think this one will surely will help you.
Availiable third party libraries available below, depend on developer choice this, which is best?
NSXMLParser
libxml2
TBXMLParser
TouchXMLParser
KissXMLParser
TinyXMLParser
GDataXMLParser
And you can also get more information from this great tutorial link
http://www.raywenderlich.com/553/how-to-chose-the-best-xml-parser-for-your-iphone-project
Try this:
XMLReader.h
//
// XMLReader.h
//
//
#import <Foundation/Foundation.h>
#interface XMLReader : NSObject <NSXMLParserDelegate>
{
NSMutableArray *dictionaryStack;
NSMutableString *textInProgress;
NSError *errorPointer;
}
+ (NSDictionary *)dictionaryForPath:(NSString *)path error:(NSError **)errorPointer;
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)errorPointer;
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)errorPointer;
#end
XMLReader.m
//
// XMLReader.m
//
#import "XMLReader.h"
//NSString *const kXMLReaderTextNodeKey = #"text";
#interface XMLReader (Internal)
- (id)initWithError:(NSError **)error;
- (NSDictionary *)objectWithData:(NSData *)data;
#end
#implementation XMLReader
#pragma mark -
#pragma mark Public methods
+ (NSDictionary *)dictionaryForPath:(NSString *)path error:(NSError **)errorPointer
{
NSString *fullpath = [[NSBundle bundleForClass:self] pathForResource:path ofType:#"xml"];
NSData *data = [[NSFileManager defaultManager] contentsAtPath:fullpath];
NSDictionary *rootDictionary = [XMLReader dictionaryForXMLData:data error:errorPointer];
return rootDictionary;
}
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)error
{
XMLReader *reader = [[XMLReader alloc] initWithError:error];
NSDictionary *rootDictionary = [reader objectWithData:data];
[reader release];
return rootDictionary;
}
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)error
{
NSArray* lines = [string componentsSeparatedByString:#"\n"];
NSMutableString* strData = [NSMutableString stringWithString:#""];
for (int i = 0; i < [lines count]; i++)
{
[strData appendString:[[lines objectAtIndex:i] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]];
}
NSData *data = [strData dataUsingEncoding:NSUTF8StringEncoding];
return [XMLReader dictionaryForXMLData:data error:error];
}
#pragma mark -
#pragma mark Parsing
- (id)initWithError:(NSError **)error
{
if ((self = [super init]))
{
errorPointer = *error;
}
return self;
}
- (void)dealloc
{
[dictionaryStack release];
[textInProgress release];
[super dealloc];
}
- (NSDictionary *)objectWithData:(NSData *)data
{
// Clear out any old data
[dictionaryStack release];
[textInProgress release];
dictionaryStack = [[NSMutableArray alloc] init];
textInProgress = [[NSMutableString alloc] init];
// Initialize the stack with a fresh dictionary
[dictionaryStack addObject:[NSMutableDictionary dictionary]];
// Parse the XML
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:data];
parser.delegate = self;
BOOL success = [parser parse];
[parser release];
// Return the stack's root dictionary on success
if (success){
NSDictionary *resultDict = [dictionaryStack objectAtIndex:0];
return resultDict;
}
return nil;
}
# pragma mark
# pragma mark - NSXMLParserDelegate methods
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
// Get the dictionary for the current level in the stack
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
// Create the child dictionary for the new element
NSMutableDictionary *childDict = [NSMutableDictionary dictionary];
// Initialize child dictionary with the attributes, prefixed with '#'
for (NSString *key in attributeDict) {
[childDict setValue:[attributeDict objectForKey:key]
forKey:key];
}
// If there's already an item for this key, it means we need to create an array
id existingValue = [parentDict objectForKey:elementName];
if (existingValue){
NSMutableArray *array = nil;
if ([existingValue isKindOfClass:[NSMutableArray class]]){
// The array exists, so use it
array = (NSMutableArray *) existingValue;
}
else{
// Create an array if it doesn't exist
array = [NSMutableArray array];
[array addObject:existingValue];
// Replace the child dictionary with an array of children dictionaries
[parentDict setObject:array forKey:elementName];
}
// Add the new child dictionary to the array
[array addObject:childDict];
}
else{
// No existing value, so update the dictionary
[parentDict setObject:childDict forKey:elementName];
}
// Update the stack
[dictionaryStack addObject:childDict];
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
// Update the parent dict with text info
NSMutableDictionary *dictInProgress = [dictionaryStack lastObject];
// Pop the current dict
[dictionaryStack removeLastObject];
// Set the text property
if ([textInProgress length] > 0){
if ([dictInProgress count] > 0){
[dictInProgress setObject:textInProgress forKey:kXMLReaderTextNodeKey];
}
else{
// Given that there will only ever be a single value in this dictionary, let's replace the dictionary with a simple string.
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
id parentObject = [parentDict objectForKey:elementName];
// Parent is an Array
if ([parentObject isKindOfClass:[NSArray class]]){
[parentObject removeLastObject];
[parentObject addObject:textInProgress];
}
// Parent is a Dictionary
else{
[parentDict removeObjectForKey:elementName];
[parentDict setObject:textInProgress forKey:elementName];
}
}
// Reset the text
[textInProgress release];
textInProgress = [[NSMutableString alloc] init];
}
// If there was no value for the tag, and no attribute, then remove it from the dictionary.
else if ([dictInProgress count] == 0){
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
[parentDict removeObjectForKey:elementName];
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
// Build the text value
[textInProgress appendString:[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]];
}
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError
{
// Set the error pointer to the parser's error object
if (errorPointer)
errorPointer = parseError;
}
#end
Use it:
NSMutableDictionary *yourDic= (NSMutableDictionary *)[XMLReader dictionaryForXMLData:yourData error:&error];

XML parser SDK for IOS

I need to be able to parse XML for a project I'm working on.
How can I parse XML from a web page to the iPhone then read its contents?
Follow this , how to parse XML in Objective c using ASIHTTPRequest and handle all this methods
-(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict
-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
See this link too
NSString *url=#"http://www.lancers.jp/work";
NSData *data=[NSData dataWithContentsOfURL:[NSURL URLWithString:url]];
NSDictionary *dict=[XMLParser dictionaryForXMLData:data error:nil];
NSLog(#"%#",[dict description]);
and use below file::::::
XMLParser.h
//
// XMLReader.h
//
// Created by Troy on 9/18/10.
// Copyright 2010 Troy Brant. All rights reserved.
//
#import <Foundation/Foundation.h>
#interface XMLParser : NSObject<NSXMLParserDelegate>
{
NSMutableArray *dictionaryStack;
NSMutableString *textInProgress;
NSError **errorPointer;
}
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)errorPointer;
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)errorPointer;
#end
XMLParser.m
//
// XMLReader.m
//
// Created by Troy on 9/18/10.
// Copyright 2010 Troy Brant. All rights reserved.
//
#import "XMLParser.h"
NSString *const kXMLReaderTextNodeKey = #"text";
#interface XMLParser (Internal)
- (id)initWithError:(NSError **)error;
- (NSDictionary *)objectWithData:(NSData *)data;
#end
//NSString *url=[NSString stringWithFormat:#"%#",NSLocalizedString(#"locationname", nil)];
//url=[NSString stringWithFormat:url,app.latnear,app.lngnear];
//NSData *data=[NSData dataWithContentsOfURL:[NSURL URLWithString:url]];
//NSDictionary *dict=[XMLReader dictionaryForXMLData:data error:nil];
#implementation XMLParser
#pragma mark -
#pragma mark Public methods
+ (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)error
{
XMLParser *reader = [[XMLParser alloc] initWithError:error];
NSDictionary *rootDictionary = [reader objectWithData:data];
[reader release];
return rootDictionary;
}
+ (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)error
{
NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
return [XMLParser dictionaryForXMLData:data error:error];
}
#pragma mark -
#pragma mark Parsing
- (id)initWithError:(NSError **)error
{
if (self = [super init])
{
errorPointer = error;
}
return self;
}
- (void)dealloc
{
[dictionaryStack release];
[textInProgress release];
[super dealloc];
}
- (NSDictionary *)objectWithData:(NSData *)data
{
// Clear out any old data
[dictionaryStack release];
[textInProgress release];
dictionaryStack = [[NSMutableArray alloc] init];
textInProgress = [[NSMutableString alloc] init];
// Initialize the stack with a fresh dictionary
[dictionaryStack addObject:[NSMutableDictionary dictionary]];
// Parse the XML
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:data];
parser.delegate = self;
BOOL success = [parser parse];
// Return the stack's root dictionary on success
if (success)
{
NSDictionary *resultDict = [dictionaryStack objectAtIndex:0];
return resultDict;
}
return nil;
}
#pragma mark -
#pragma mark NSXMLParserDelegate methods
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
// Get the dictionary for the current level in the stack
NSMutableDictionary *parentDict = [dictionaryStack lastObject];
// Create the child dictionary for the new element, and initilaize it with the attributes
NSMutableDictionary *childDict = [NSMutableDictionary dictionary];
[childDict addEntriesFromDictionary:attributeDict];
// If there's already an item for this key, it means we need to create an array
id existingValue = [parentDict objectForKey:elementName];
if (existingValue)
{
NSMutableArray *array = nil;
if ([existingValue isKindOfClass:[NSMutableArray class]])
{
// The array exists, so use it
array = (NSMutableArray *) existingValue;
}
else
{
// Create an array if it doesn't exist
array = [NSMutableArray array];
[array addObject:existingValue];
// Replace the child dictionary with an array of children dictionaries
[parentDict setObject:array forKey:elementName];
}
// Add the new child dictionary to the array
[array addObject:childDict];
}
else
{
// No existing value, so update the dictionary
[parentDict setObject:childDict forKey:elementName];
}
// Update the stack
[dictionaryStack addObject:childDict];
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
// Update the parent dict with text info
NSMutableDictionary *dictInProgress = [dictionaryStack lastObject];
// Set the text property
if ([textInProgress length] > 0)
{
[dictInProgress setObject:textInProgress forKey:kXMLReaderTextNodeKey];
// Reset the text
[textInProgress release];
textInProgress = [[NSMutableString alloc] init];
}
// Pop the current dict
[dictionaryStack removeLastObject];
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
// Build the text value
[textInProgress appendString:string];
}
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError
{
// Set the error pointer to the parser's error object
*errorPointer = parseError;
}
#end