DSTViewController.m

Insert the file with some old name here. y

- (void) prepareForSegue:(UIStoryboardSegue *)segue                   sender:(id)sender {     UIViewController *newViewController = segue.destinationViewController;     newViewController.view.backgroundColor = [UIColor greenColor]; }

Change the variable name from greenViewController to newViewController.

New Text

- (void) prepareForSegue:(UIStoryboardSegue *)segue                   sender:(id)sender {     UIViewController *newViewController = segue.destinationViewController;     if ([segue.identifier isEqualToString:@"showGreenScene"]) {         newViewController.view.backgroundColor = [UIColor greenColor];     } }

Only change the background color to green if the segue identifier is showGreenScene.

Similarly, color the target view blue if the identifier is showBlueScene.

- (void) prepareForSegue:(UIStoryboardSegue *)segue                   sender:(id)sender {     UIViewController *newViewController = segue.destinationViewController;     if ([segue.identifier isEqualToString:@"showGreenScene"]) {         newViewController.view.backgroundColor = [UIColor greenColor];     } else if ([segue.identifier isEqualToString:@"showBlueScene"]) {         newViewController.view.backgroundColor = [UIColor blueColor];     } }