iOS connecting to webservice

[McBgnr]

Hello,

I want to write an application to connect to a webservice for iPhone. I am not sure how to start on this. What are the APIs that I would be needed for this purpose.

I am using SDK 3.0.

Cheers
McBgnr

 

[robbieduncan]

Read the NSURLConnection documentation.

 

[McBgnr]

Thanks for the input. I will check it out. Dont know how to pass the method name though!.

Meanwhile I was looking at the Webservices reference doc at apple documentation. It says to use WSMethodInvocationRef, but when I tried to use this in my project it gives compiler error. (undeclared). The coreservices framework is included in the project. Any other things that I may have missed out?

 

[robbieduncan]

Thanks for the input. I will check it out. Dont know how to pass the method name though!.

Meanwhile I was looking at the Webservices reference doc at apple documentation. It says to use WSMethodInvocationRef, but when I tried to use this in my project it gives compiler error. (undeclared). The coreservices framework is included in the project. Any other things that I may have missed out?

You need to be very careful when reading the documentation: don't read the Mac OSX Core Foundation documents: read the iPhone ones. A search for WSMethodInvocationRef in the iPhone dev center returns nothing...

 

[McBgnr]

Oh ... my mistake... Will be more careful going forward regarding this. Thanks a bunch for correcting me.

 

[mayurnilwant]

expected declaration specifiers or '...' before 'CFXMLTreeRef'

I have included core services and Core Foundationn frameworks but it still doesn't work where in the correct frame work in my directory.... cn ne body gv me the path....

 

[sjames]

Here is some code which use the NSURLConnection to construct a request and process the response.

- (IBAction)fetchBooks:(id)sender
{
	NSLog(@"fetchBooks");
	//show user something is happending
	[progress startAnimation:nil];
	//get the value we are looking for
	NSString *input = [searchField stringValue];
	//escaping
	NSString *searchString = [input stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
	NSLog(@"searchString = %@",searchString);
	//create the URL		
	NSString *urlString =[NSString stringWithFormat:
						  @"http://ecs.amazonaws.com/onca/xml?"
						  @"Service=AWSECommerceService&"
						  @"AWSAccessKeyId=%@&"
						  @"Operation=ItemSearch&"
						  @"SearchIndex=Books&"
						  @"Keywords=%@&"
						  @"Version=2007-07-16",
						  AWS_ID,searchString];
	
	NSLog(@"url - %@",urlString);
	
	NSString *signedURLString = [HMACSHA256 getSignedRequest:urlString withSecret:AWS_SECRET];
	NSLog(@"signed url %@",signedURLString);
	NSURL *url	= [NSURL URLWithString:signedURLString];

	
	
	NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url
												  cachePolicy:NSURLRequestReturnCacheDataElseLoad
												 timeoutInterval:30];
	//fetch the response
	NSData *urlData;
	NSURLResponse *response;
	NSError *error;
	urlData = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&response error:&error];
	//check for errors in repsonse
	if(!urlData){
		NSAlert *alert = [NSAlert alertWithError:error];
		[alert runModal];
		return;
	}
	//parse the response
	[doc release];
	doc = [[NSXMLDocument alloc] initWithData:urlData options:0 error:&error];
	NSLog(@"doc = %@",doc);
	if(!doc){
		NSAlert *alert = [NSAlert alertWithError:error];
		[alert runModal];
		return;
	}
	[itemNodes release];
	itemNodes = [[doc nodesForXPath:@"ItemSearchResponse/Items/Item" error:&error] retain];
	if(!itemNodes){
		NSAlert *alert = [NSAlert alertWithError:error];
		[alert runModal];
		return;
	}
	//update interface
	[tableView reloadData];
	[progress stopAnimation:nil];
}