collisionViewController should conform your protocol.
collisionViewController.h
#import "SelectVehicleViewController.h"
@interface ContactViewController : UIViewController <SelectVehicleDelegate>
collisionViewController.m
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqual:@"segueName"]) {
SelectVehicleViewController* VC = segue.destinationViewController;
VC.delegate = self;
//here you should probably send if you will select the vehicule 1 or 2
}
}
- (void)ViewController:(UIViewController *)sender
didUpdateData:(NSString *)value {
//do what you need with new data
//here you should have info if it is for vehicle 1 or 2
}
SelectVehicleViewController.h
@protocol SelectVehicleDelegate;
@interface SelectVehicleViewController : UIViewController
@property (nonatomic, assign) id <SelectVehicleDelegate> delegate;
@end
@protocol SelectVehicleDelegate <NSObject>
- (void)ViewController:(UIViewController *)sender
didUpdateData:(NSString *)value; //adapte according to what you should send back
@end
SelectVehicleViewController.m
//somewhere in a button click or....
[self.delegate ViewController:self didUpdateData:@"new value"];
//in this function you should have info if it is for vehicle 1 or 2