for(UIViewController *controller in self.navigationController.viewControllers) {
NSString *className = NSStringFromClass([controller class]);
NSLog(@"--className--%@",className);
if([controller isKindOfClass:[CategoriesViewController class]]){
CategoriesViewController *viewCon = (CategoriesViewController *)controller;
[self.navigationController popToViewController:viewCon animated:YES];
}
}