How can I sign in using twitter framework or social framework in iOS properly? - objective-c

Question

NSURL *url = [NSURL URLWithString:#"https://api.twitter.com/1.1/users/show.json"];
NSDictionary *params = [NSDictionary dictionaryWithObjectsAndKeys:twittername,#"screen_name",nil];
request = [[TWRequest alloc] initWithURL:url parameters:params requestMethod:TWRequestMethodGET];
ACAccountStore *accountStore = [[ACAccountStore alloc] init];
ACAccountType *twitterAccountType = [accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
NSArray *twitterAccounts = [accountStore accountsWithAccountType:twitterAccountType];
// Runing on iOS 6
if (NSClassFromString(#"SLComposeViewController") && [SLComposeViewController isAvailableForServiceType:SLServiceTypeTwitter])
{
[accountStore requestAccessToAccountsWithType:twitterAccountType options:NULL completion:^(BOOL granted, NSError *error)
{
if (granted)
{
SLRequest *request = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodGET URL:url parameters:parameters];
[request setAccount:[twitterAccounts lastObject]];
dispatch_async(dispatch_get_main_queue(), ^
{
[NSURLConnection sendAsynchronousRequest:request.preparedURLRequest queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response1, NSData *data, NSError *error)
{
dispatch_async(dispatch_get_main_queue(), ^
{
if (data)
{
[self loadData:data];
}
});
}];
});
}
}];
}
else if (NSClassFromString(#"TWTweetComposeViewController") && [TWTweetComposeViewController canSendTweet]) // Runing on iOS 5
{
[accountStore requestAccessToAccountsWithType:twitterAccountType withCompletionHandler:^(BOOL granted, NSError *error)
{
if (granted)
{
TWRequest *request = [[TWRequest alloc] initWithURL:url parameters:parameters requestMethod:TWRequestMethodGET];
[request setAccount:[twitterAccounts lastObject]];
dispatch_async(dispatch_get_main_queue(), ^
{
[NSURLConnection sendAsynchronousRequest:request.signedURLRequest queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response1, NSData *data, NSError *error)
{
dispatch_async(dispatch_get_main_queue(), ^
{
if (data)
{
[self loadData:data];
}
});
}];
});
}
}];
}
}
While implementing this code, Here I am getting few errors,
NSDictionary *params = [NSDictionary dictionaryWithObjectsAndKeys:twittername,#"screen_name",nil];
twittername is undeclared. can any tell what is right parameter here?