Programmatically segue..works ever - ios

Question

I'm trying to create a manual segue, which happens only if there is a certain conidition (a successful login).
The steps I have followed are these:
1) I've created a button in source viewcontroller, and i connected the button with a drag with the destination viewcontroller.
2) I set the identifier for the segue, calling it login_ok
3) I've created a -(IBAction)buttonPressed:(id)sender
Now, I tried to make an example, to see if the work or not. I wrote:
- (IBAction)buttonPressed:(id)sender
{
BOOL test = false;
if(test == true)
{
[self performSegueWithIdentifier:#"login_ok" sender:self];
}
Theoretically, the segue should not work, because i set test=false, and i said the segue should work only if test=true.
But the segue works and makes me go to the destination viewcontroller.
Why?

Answer 1

If you connected the button with a drag to the destination controller, it should segue anyway.
You need to connect the segue between screens and not from the button to the screen. Then, you can control your segue from the code.

Answer 2

You should define your segue between controllers not from button to the controller. Defining segue between view controllers is more useful than defining segue from any component to a view controller, because when you want to use a condition for any action, you can use these two methods effectively
[self performSegueWithIdentifier:#"segueID" sender:self];
and
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
For example:
- (IBAction)buttonPressed:(id)sender
{
BOOL test = YES;
if(test == YES)
[self performSegueWithIdentifier:#"login_ok" sender:self];
}
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"login_ok"])
{
YourNextController *controller = [segue destinationViewController];
controller.welcomeText = #"Hi! Test is true congratulations";
}
}
Especially passing data from controller to another one, this way is always useful.