Calling method to view controller delegate, won't dismiss modal view

Question

I have the following simple view controller class set up

@protocol ThermoFluidsSelectorViewControllerDelegate;

@interface ThermoFluidsSelectorViewController : UIViewController <UITextFieldDelegate>
@property (weak, nonatomic) id <ThermoFluidsSelectorViewControllerDelegate> delegate;
// user hits done button
- (IBAction)done:(id)sender;
@end

@protocol ThermoFluidsSelectorViewControllerDelegate <NSObject>
-(void) didFinishSelection:(ThermoFluidsSelectorViewController *)controller fluidID:    (NSString *)fluidID;
@end

the 'didFinishSeletion: fluidID:' method is defined in the master view controller and should dismiss the selector view controller when called. When the done button is pressed the following method is called:

- (IBAction)done:(id)sender
{
    [[self delegate] didFinishSelection:self fluidID:nil];
}

the 'done:' method gets called (checked with an alert) but 'didFinishSelection...' is not getting called so the view will not revert back to the main screen. Any ideas?

Answer 1

It sounds like you have not assigned your delegate in your master view controller.

You should have something like this in your master view controller which sets up the delegate:

    ThermoFluidsSelectorViewController *view = [[ThermoFluidsSelectorViewController alloc] init];
    view.delegate = self;

here you can see I create the view, then set the delegate of the view back to myself.

If you are not creating the Thermo... view controller programatically, but have used a storyboard, then you can set the delegate in the prepareForSegue: method of your master view controller:

// Do some customisation of our new view when a table item has been selected
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Make sure we're referring to the correct segue
    if ([[segue identifier] isEqualToString:@"MySegueID"]) {

    // Get reference to the destination view controller
    ThermoFluidsSelectorViewController *cont = [segue destinationViewController];

    // set the delegate
    cont.delegate = self;

Hope this helps.