This is a comprehensive slide on implementing web service in iOS . There are basic information on Web Service . There are steps of using web service in iOS. The presentation emphasized on XML Parsing .

1. Working with Web Service in iOS

2. Syed Mahboob Nur
iOS Developer
Blog: http://mahboobiosdeveloper.blogspot.com/
Fb Profile:
https://www.facebook.com/mahboob.nur
Meetnar Profile:
http://www.meetnar.com/Home/UserDetails/24

3. Web Service
A Web service is a method of communications
between two electronic devices over the World
Wide Web. It is a software function provided at
a network address over the web with the service
always on as in the concept of utility computing.

5. Several Types of Web Services
WSDL
• WSDL stands for Web Services Description
Language
• WSDL is an XML-based language for describing
Web services.
• WSDL is a W3C recommendation

6. Several Types of Web Services
SOAP
• SOAP stands for Simple Object Access Protocol
• SOAP is an XML based protocol for accessing
Web Services.
• SOAP is based on XML
• SOAP is a W3C recommendation

7. Several Types of Web Services
UDDI
• UDDI stands for Universal Description,
Discovery and Integration
• UDDI is a directory service where companies
can search for Web services.
• UDDI is described in WSDL
• UDDI communicates via SOAP

8. Several Types of Web Services
RDF
• RDF stands for Resource Description
Framework
• RDF is a framework for describing resources
on the web
• RDF is written in XML
• RDF is a W3C Recommendation

10. Advantage of Using Web Service in
Mobile Application
•
•
•
•
Minimize application size
Minimize Code Size
Easy to modify
Reuse Application

11. Disadvantage of Using Web Service in
Mobile Application
• Internet Connection Required
• Server have to be active 24/7

12. Working with Web Service in iOS
(WSDL)
WSDL is an XML format for describing network
services as a set of endpoints operating on
messages containing either document-oriented
or procedure-oriented information. The
operations and messages are described
abstractly, and then bound to a concrete
network protocol and message format to define
an endpoint. Related concrete endpoints are
combined into abstract endpoints (services)

13. WSDL Example
<xml>
<types> <schema targetNamespace="http://example.com/
stockquote.xsd" xmlns="http://www.w3.org/2000/10/
XMLSchema"> <element name="TradePriceRequest">
<complexType>
<all> <element name="tickerSymbol" type="string"/>
</all>
</complexType> </element> <element name="TradePrice">
<complexType>
<all> <element name="price" type="float"/>
</all>
</complexType> </element> </schema>
</types>
</xml>

14. Steps of Implementing XML Service in
IOS
• Create a XML Parser file as NSObject type.
• Write relevant code in the files.
• Call the XML Parser class in a View Controller
Class and load XML by url .
• Parse the data and load in the containers or
view components. Example : Table View,
Picker View, Labels, Text Field etc.

15. Create a XML Parser file as NSObject
type.
#import <Foundation/Foundation.h>
//#import "TeamViewController.h"
#import "TeamInfo.h"
@interface TeamParser : NSObject<NSXMLParserDelegate>
{
NSString *currentNodeImage;
NSString *currentNodeName;
NSXMLParser
*parser;
NSMutableArray *imageArray;
NSMutableArray *nameArray;
TeamInfo*teamInfo;
}
@property (nonatomic, retain) NSMutableArray *imageArray;
@property (nonatomic, retain) NSMutableArray *nameArray;
-(id) loadXMLByURL:(NSString *)urlString;
@end

16. .m file implementation
#import "TeamParser.h"
@implementation TeamParser
@synthesize imageArray;
-(id) loadXMLByURL:(NSString *)urlString
{
imageArray= [[NSMutableArray alloc] init];
nameArray=[[NSMutableArray alloc]init];
NSURL *url = [NSURL URLWithString:urlString];
//parser = [[NSXMLParser alloc] initWithData:aData];
parser= [[NSXMLParser alloc] initWithContentsOfURL:url];
//parser = [[NSXMLParser alloc] initWithData:aData];
parser.delegate=self;
[parser parse];
return self;
}

17. - (void) parser:(NSXMLParser *)parser didStartElement:(NSString
*)elementname namespaceURI:(NSString *)namespaceURI
qualifiedName:(NSString *)qName attributes:(NSDictionary
*)attributeDict
{
if ([elementname isEqualToString:@"team"])
{
currentNodeImage=[[NSString alloc] init] ;
currentNodeName=[[NSString alloc]init];
teamInfo=[[TeamInfo alloc]init];
}
}

18. - (void) parser:(NSXMLParser *)parser didEndElement:(NSString *)elementname
namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
if ([elementname isEqualToString:@"logo"]) {
teamInfo.teamLogo = currentNodeImage;
//NSLog(@"image:%@",currentNodeImage);
}
if ([elementname isEqualToString:@"name"]) {
teamInfo.teamName = currentNodeImage;
//NSLog(@"name:%@",currentNodeImage);
}
if ([elementname isEqualToString:@"team"])
{
[imageArray addObject:teamInfo];
[currentNodeImage release];
[currentNodeName release];
currentNodeImage = nil;
currentNodeName=Nil;
}

19. Call the XML Parser class in a View
Controller Class and load XML by url .
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:YES];
teamImageParser = [[TeamParser alloc]
loadXMLByURL:@"http://www.amarhost.info/sabbir/iOS/AsiaCup/Services/teamlog
o.xml"];
imageNameArray=teamImageParser.imageArray;
teamNameArray=teamImageParser.nameArray;
for(int i=0;i<[imageNameArray count];i++)
{
NSLog(@"%@",[imageNameArray objectAtIndex:i]);
}
for(int i=0;i<[teamNameArray count];i++)
{
NSLog(@"%@",[teamNameArray objectAtIndex:i]);

20. Plot Parsed Data in the TableView
- (NSInteger)numberOfSectionsInTableView:(UITableView
*)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView
numberOfRowsInSection:(NSInteger)section
{
return [[teamImageParser imageArray] count];
}

21. Plot Parsed Data in the TableView
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath
*)indexPath
{
static NSString *CellIdentifier = @"TeamCustomCell";
TeamCustomCell *cell = (TeamCustomCell*)[teamTableView
dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
NSArray *topLabelObject = [[NSBundle mainBundle]
loadNibNamed:@"TeamCustomCell" owner:self options:nil];
for (id currentObject in topLabelObject)
{
if ([currentObject isKindOfClass:[UITableViewCell class]])
{
cell = (TeamCustomCell*) currentObject;
break;

22. TeamInfo *teamInfo;
teamInfo = [[teamImageParser imageArray] objectAtIndex:indexPath.row];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
cell.headerTextLabel.text=teamInfo.teamName;
NSLog(@"teamName: %@",teamInfo.teamName);
imageQueueTeamLogo = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH,
0ul);
dispatch_async(imageQueueTeamLogo, ^
{
UIImage *imageTVGuideLogo = [UIImage imageWithData:[NSData
dataWithContentsOfURL: [NSURL URLWithString:[teamInfo teamLogo]]]];
dispatch_async(dispatch_get_main_queue(), ^
{
cell.titleImageView.image = imageTVGuideLogo;
[cell setNeedsLayout];
});
});
return cell;
}

24. That’s all for today