Objective-c – Storyboard and custom init

objective cstoryboarduiviewcontroller

I recently tried working with the MainStoryboard.storyboard within Xcode and so far It's going pretty good and I'm wondering why I've never used it before. While playing with some code I bumped into an obstacle and I don't know how to resolve this.

When I alloc and init a new ViewController (with a custom init I declared in the ViewControllers class) I would do something like this:

ViewController *myViewController = [[ViewController alloc] initWithMyCustomData:myCustomData];

Then after that I could do something like:

[self presentViewController:myViewController animated:YES completion:nil];

When I'm working with a storyboard I'm learnt that switching to a standalone ViewController requires an Identifier.

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
ViewController *myViewController = [storyboard instantiateViewControllerWithIdentifier:@"MyViewControllerIdentifier"];
[self presentViewController:myViewController animated:YES completion:nil];

How can I still use my custom initialization for myViewController while making use of a storyboard?

Is it ok to just do something like this:

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
ViewController *myViewController = [storyboard instantiateViewControllerWithIdentifier:@"MyViewControllerIdentifier"];
myViewController.customData = myCustomData;
[self presentViewController:myViewController animated:YES completion:nil];




//MyViewController.m
- (id) initWithMyCustomData:(NSString *) data {
if (self = [super init]) {
    iVarData = data;
}
return self;
}

Best Answer

I would just create a method which does the custom data loading.

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
MyViewController *myViewController = [storyboard instantiateViewControllerWithIdentifier:@"MyViewControllerIdentifier"];
[myViewController loadCustomData:myCustomData];
[self presentViewController:myViewController animated:YES completion:nil];

If all your initWithCustomData method does is set one instance variable, you should just set it manually (no custom inits or extra methods required):

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
MyViewController *myViewController = [storyboard instantiateViewControllerWithIdentifier:@"MyViewControllerIdentifier"];
myViewController.iVarData = myCustomData;
[self presentViewController:myViewController animated:YES completion:nil];

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