Using GDataXMLDocument in iPad app

I'm trying to use GDataXML library in my ipad application. I followed by instructions:

Download the gdata-objective-c client library.
Unzip the file, navigate to Source\XMLSupport, and drag the two files GDataXMLNode.h and GDataXMLNode.m into your project
In XCode, click Project\Edit Project Settings and make sure “All Configurations” are checked.
Find the Search Paths\Header Search Paths setting and add /usr/include/libxml2 to the list.
Finally, find the Linking\Other Linker Flags section and add -lxml2 to the list.

If in code i add #import "GDataXMLNode.h", all is fine. But when i try to use GDataXMLDocument class in my app

GDataXMLDocument *doc = [[GDataXMLDocument alloc] initWithData:xmlData options:0 error:nil];

I received the following message:

Ld build/Debug-iphonesimulator/DemoApp.app/DemoApp normal i386
cd /Users/svp/Projects/DemoApp
setenv MACOSX_DEPLOYMENT_TARGET 10.6
setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.2 -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.2.sdk -L/Users/svp/Projects/DemoApp/build/Debug-iphonesimulator -F/Users/svp/Projects/DemoApp/build/Debug-iphonesimulator -filelist /Users/svp/Projects/DemoApp/build/DemoApp.build/Debug-iphonesimulator/DemoApp.build/Objects-normal/i386/DemoApp.LinkFileList -mmacosx-version-min=10.6 -Xlinker -objc_abi_version -Xlinker 2 -framework Foundation -framework UIKit -framework CoreGraphics -framework MapKit -framework QuartzCore -lxml2.2 -o /Users/svp/Projects/DemoApp/build/Debug-iphonesimulator/DemoApp.app/DemoApp

Undefined symbols:
  "_OBJC_CLASS_$_GDataXMLDocument", referenced from:
      objc-class-ref-to-GDataXMLDocument in TwitterService.o
ld: symbol(s) not found
collect2: ld returned 1 exit status

Any thoughts?

Solution

Best thing is to leave the source code untouched and tell your project not to apply the ARC mechanism to this file. To do so: 1- Select the build phases of your projet 2- Select the GDataXMLNode.m file 3- Add the switch: -fno-objc-arc to this file alone (by double clicking on it)

Bingo!

Hope it helps.