use of undeclared identifier - objective-c

Question

I am new to Objective-C coding ,please bear with me to ask if this is simple question
My Header file:
#import <Cocoa/Cocoa.h>
#interface AppDelegate : NSObject <NSApplicationDelegate>
#property (assign) IBOutlet NSWindow *window;
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification;
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse*) response;
#end
My Implementation file:
#import "AppDelegate.h"
#implementation AppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
// Insert code here to initialize your application
NSMutableData *receivedData =[NSMutableData dataWithCapacity: 0];
// Create the request
NSURLRequest *theRequest=[NSURLRequest requestWithURL:[NSURL URLWithString:#"http://www.apple.com/"] cachePolicy:NSURLRequestUseProtocolCachePolicy
timeoutInterval:60.0];
// Create the NSMutableData to hold the received data.
// receivedData is an instance variable declared elsewhere.
receivedData = [NSMutableData dataWithCapacity: 0];
// create the connection with the request
// and start loading the data
NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
if (!theConnection) {
// Release the receivedData object.
receivedData = nil;
// Inform the user that the connection failed.
}
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
NSMutableData *receivedData =[NSMutableData dataWithCapacity:0];
// This method is called when the server has determined that it
// has enough information to create the NSURLResponse object.
// It can be called multiple times, for example in the case of a
// redirect, so each time we reset the data.
// receivedData is an instance variable declared elsewhere.
[receivedData setLength:0];
}
#end
when i run the code at implementation appDelegate it gives warning
Method definition for connection:didRecieveResponse :not found
and where
-(void)connection line it gives "use of undelcared identifier connection did u mean Collection".

Answer 1

You do not need to declare the method
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse*) response;
in your header file if you are using the NSURLConnectionDataDelegate Protocol in your code. Just add the protocol in the implementation and use the methods from that protocol.