OK, a couple of things need to change in you function definition.
First you need a - at the front not a +. The plus denotes a class method whereas the - is for an instance method. You are using this like an instance method.
Second you need to include MainViewController.h in your SocialClass.h file. Then name the function like...
- (void)facebookForIosSix:(NSString *)url image:(NSString *)img status:(NSString *)text viewCont:(MainViewController *)mainViewController;
Then in mainViewController you can run...
[socialViewController facebookSharingStatusCheckCall:@"url" image:@"hello.png" status:@"Posting from App" viewCont:self];
this should work fine.
EDIT
If you want to run the function fro multiple places then don't import MainViewController.h and define the function like...
- (void)facebookForIosSix:(NSString *)url image:(NSString *)img status:(NSString *)text viewCont:(UIViewController *)viewController;
then run it like...
[socialViewController facebookSharingStatusCheckCall:@"url" image:@"hello.png" status:@"Posting from App" viewCont:(UIViewController*)self];
TBH, I don't think you'll need to cast it at all but just to be safe you can.
EDIT
You haven't balanced your brackets...
- (IBAction)facebookShareBtn:(id)sender {
[socialClass facebookSharingStatusCheckCall:[[DataPassing sharedManager] pageURL ]
image:[[DataPassing sharedManager] pageIMGurl]
status:[[DataPassing sharedManager] pageTEXT]
viewCont:(UIViewController*)self];
}
This will work.