How to navigate with popViewController - ios

Question

I'm new to iOS development and I'm using parse.com as my backend.
I want to navigate from [View Controller 2] to [view Controller 3]
but is not working right.
Here is the code
http://i.stack.imgur.com/t6zZg.jpg
NSString *username = [self.usernameField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
NSString *password = [self.passwordField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
NSString *email = [self.emailField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
if ([username length] == 0 || [password length] == 0 || [email length] == 0){
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:#"Oops!" message:#"Make sure you enter a username, password , and email address!" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alertView show]; // This help to show your message successfully!
}
else {
PFUser *newUser = [PFUser user]; // This is a method to create new users
newUser.username = username;
newUser.password = password;
newUser.email = email;
[newUser signUpInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
if (error) {
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:#"Sorry!" message:[error.userInfo objectForKey:#"error"] delegate:nil cancelButtonTitle:#"OK" otherButtonTitles: nil];
[alertView show];
}
else {
[self.navigationController popToViewController:_profilePhotoViewController animated:YES];
}
}];
}
}

Answer 1

According to the image you posted, VC3 is not displayed nor pushed to the controller before displaying VC2
This method popToViewController:animated: require that the controller is displayed before and in the controller stack in order to pop the stack back to it
You can achieve what you want by pop to root and then push your view
[self.navigationController popToRootViewControllerAnimated:NO];
[self.navigationController pushViewController:_profilePhotoViewController animated:YES];
Besure that _profilePhotoViewController is allocated before pushing it
.
.
UPDATE
In your storyboard set an identifier to your VC3 to be for example "VC3Identifier"
You can do this as you can see in the below image
Choose your controller
Show the utilities
show the identity inspector
Put 'VC3Identifier' in StoryBoard ID field
Then You will need to allocate a new instance of this controller and add it to the navigation controller
YourController *vc3 = [self.storyboard instantiateViewControllerWithIdentifier:#"VC3Identifier"];
[self.navigationController setViewControllers:#[vc3] animated:YES];

Answer 2

OK, well, I am not totally sure how your code works and what will trigger the change of View, but in your code where you call this:
[self.navigationController popToViewController:_profilePhotoViewController animated:YES];
Is what you need to handle (assuming profilePhotoViewController is VC3).
Go to your Storyboard and ctrl+click+drag from the presenting view (the VC that you are starting from) and end up at VC 3. VC 3 should light up blue. Let go and you will see a drop down menu. Select "Push". This will create a segue for you to transition. Next you need to give it an identifier, so click on the segue that was just made and go to the Attributes Inspector and in the "Identifier" field type in "ProfilePictureSegue" and then press enter (or return).
Then go to the file that contains the code you posted and replace
[self.navigationController popToViewController:_profilePhotoViewController animated:YES];
With:
[self performSegueWithIdentifier:#"ProfilePictureSegue"];
And bob is your uncle. Run it.
EDIT
I looked at your picture again and it looks like your VC3 is in the wrong place. Create a segue from VC2 to VC 3, not from the Navigation Controller to VC3. Call the segue, as I explained above, in the VC2 .m file, and it will transition between.
If you need more explanations.