objective-c - Passing a dictionary between two viewcontrollers?

Question

I have an application in which I have a webservice call that returns data as a dictionary. I want to access this dictionary in another view controller for loading the values into a table.

Can anybody demonstrate how to pass this response dictionary from one view controller to another?

Answer 1

You could define an NSDictionary property in your AnotherViewController and set it from the previous controller. I'll give a brief example below.

//.h
@interface AnotherViewController {

  NSDictionary *data;
}
@property(nonatomic,retain) NSDictionary *data;
@end

//.m
@implementation AnotherViewController
@synthesize data;

Now from the current controller, after initializing AnotherViewController you set the dictionary before presenting it.

AnotherViewController *controller = [[AnotherViewController alloc] init];
controller.data = myCurrentDictionary;

Now AnotherViewController has a data property with the value of the previous controller.

Hope this helps.

Answer 2

I am assuming that the webservice is called because something happened (button clicked, viewDidLoad/viewDidAppear). If this is the case, passing a reference of the UIViewController to the webservice class is a perfect valid option. Keep in mind that for this relationship you should create a protocol, so on your webservice class you have something like this:

id<ViewControllerResponseProtocol> referenceToViewController;

This ViewControllerResponseProtocolwould define a method like this:

-(void)responseFromWebservice:(NSDictionary*)myDictionary;

So when the webservice class has build the NSDictionary you can the above method from the referenceToViewController:

[referenceToViewController responseFromWebservice:myDictionary];

If there isn't any kind of relationship between both, you use could NSNotificationCenter for it.

P.S: The solution of skram is perfectly valid if you already have the NSDictionary from the webservice on the initial UIViewController and now you want to pass it to a new UIViewController. Although I don't think that's what you want.