Error while importing the framework

My app deals with phone call.So I added coretelephony framework to my proje开发者_Python百科ct.But when I try to import the framework to my appdelegate,I get the error "No such file directory" Can any one find the solution for that.I use xcode 4.0.1

HI after you add core telephony framework then add

#import <CoreTelephony/CoreTelephonyDefines.h> to your appDelegate.h file

It will solve your problem.