calling functions and passing information between views

Question

Thanks in advance for your help!

In the main ViewController.m of my project I am adding a customized tableView like so:

messageController = [[MyMessagesController alloc] initWithStyle:UITableViewStylePlain];
[self addChildViewController:messageController];
[self.view addSubview:messageController.view];

Then, in the MyMessagesController.m section tableView didSelectRowAtIndexPath: I'd like to write code that would take effect in the ViewController.m where it was created and added as a childViewController.

How can I access the functions of the ViewController.m from MyMessagesController.m?

Can I make it a delegate somehow so I could call [delegate functionName];? Could I pass information back to the ViewController.m? About which of the rows in table was selected by sending through an NSString or NSArray or anything?

score 1 · Answer 1 · answered Jan 29 '13 at 18:53

1

Yes, use a delegate, if you are unsure how best to accomplish this, here is a good reference from Apple about delegate programming

answered Jan 29 '13 at 18:53

Dan F

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Yes - that is what I am looking for... how do I create this view to be a delegate for the original view so that I can interact with it? – RanLearns Jan 29 '13 at 19:03
You declare a delegate protocol that has the methods you need, parameters and all, declare your child VC to have a delegate that adheres to that protocol, and make sure your parent VC implements that protocol, and then set the delegate like you would for any other object that has a delegate. All of this is laid out in the link I provided in the answer – Dan F Jan 29 '13 at 19:14

score 0 · Accepted Answer · answered Jan 29 '13 at 19:30

Got it figured out, here's how you turn one viewController into a delegate for another:

In the .h of the parent controller -

@interface ViewController : UIViewController <NameOfDelegate> {

In the .m of the parent controller, once you create the new view -

newViewController.delegate = self;

and also:

- (void)functionToCall:(id)sender {
    NSLog(@"Function Called!!!");
}

In the .h of the newViewController you're adding -

@protocol NameOfDelegate;

@interface newViewController : UIViewController/OR/TableViewController {
    id <NameOfDelegate> delegate;
}

@property (nonatomic, strong) id <NameOfDelegate> delegate;

@end

@protocol NameOfDelegate
- (void)functionToCall:(id)sender;
@end

in the .m of the newViewController -

@implementation newViewController

@synthesize delegate;

and when you're ready to call the function in your delegate -

[delegate functionToCall:self];

calling functions and passing information between views

2 Answers2