Calling Performseguewithidentifier Doesn't Call Shouldperformseguewithidentifier

When is shouldPerformSegueWithIdentifier called?

When I run it shouldPerformSegueWithIdentifier is called first and second the IBAction

Only one of them should be called. The fact that they are both called means that your storyboard configuration is incorrect (in both cases).

Using shouldPerformSegueWithIdentifier( ) method in Swift

You may not invoke shouldPerformSegueWithIdentifier() method by yourself. It will be automatically called just before transition to the next view giving a chance to determine wether the transition should take place or. You may conditionally return YES/NO from this method. If your condition does't involve any sever call,a simple logical checking this method will be enough for you.

performSegueWithIdentifier() is used to invoke a segue programmatically. Consider the above case with a network call, you may return NO from shouldPerformSegueWithIdentifier() initially since authentication is going on. After getting the response from server if it success you can call the segue to execute with performSegueWithIdentifier (Here the identifier is the ID you have given in the storyboard). Before make sure you are supposed to return YES from shouldPerformSegueWithIdentifier().

Now a third case if your segue is connecting from the login button(You have to connect it from the controller itself). The checking of shouldPerformSegueWithIdentifier is no more required. You can just call the segue with performSegueWithIdentifier() after getting the success response from server

Perform a segue only if something happens

This answer explains what's happening with your logic.

What you can do instead, check if the textfield is filled inside the button function before performing the segue.

Prevent segue in prepareForSegue method?

It's possible in iOS 6 and later:
You have to implement the method

- (BOOL)shouldPerformSegueWithIdentifier:(NSString *)identifier sender:(id)sender 

In your view controller. You do your validation there, and if it's OK then return YES; if it's not then return NO; and the prepareForSegue is not called.

Note that this method doesn't get called automatically when triggering segues programmatically. If you need to perform the check, then you have to call shouldPerformSegueWithIdentifier to determine whether to perform segue.

performSegueWithIdentifier not firing

Ok I solved my issue. It had to do with saving the currently displayed view controller when the app goes to background and then perform the segue before the app goes active. And thanks for the downvote. Really makes me feel at home!

To stop segue and show alert

If your deployment target is iOS 6.0 or later

You can simply implement the shouldPerformSegueWithIdentifier:sender: method on your source view controller. Make this method return YES if you want to perform the segue, or NO if you don't.

If your deployment target is earlier than iOS 6.0

You will need to change the way your segue is connected in the storyboard and write a little more code.

First, set up the segue from the button's view controller to the destination view controller, instead of directly from the button to the destination. Give the segue an identifier like ValidationSucceeded.

Then, connect the button to an action on its view controller. In the action, perform the validation and either perform the segue or show an alert based on whether the validation succeeded. It will look something like this:

- (IBAction)performSegueIfValid:(id)sender {
    if ([self validationIsSuccessful]) {
        [self performSegueWithIdentifier:@"ValidationSucceeded" sender:self];
    } else {
        [self showAlertForValidationFailure];
    }
}

performSegue throwing SIGABRT

sigabrt error calling segue programatically in swift

Make sure you don't have any orphaned connections from your view controller to your storyboard.

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