pass NSString variable to other class with NSNotification

Question

I want to pass a NSString from one class to another class and add that NSString to an NSMutableArray in my second class. I'm believe i can use NSNotification for this, but i don't know how to pass an variable over notification. My code would something like this: //class1.h ``` #import @interface ViewController : UIViewController @property(strong,nonatomic)NSString *variableString; @end ``` //class1.m ``` #import "ViewController.h" @interface ViewController () @end @implementation ViewController @synthesize variableString = _variableString; - (void)viewDidLoad { [super viewDidLoad]; [self setVariableString:@"test"]; [[NSNotificationCenter defaultCenter] postNotificationName: @"pasteString" object: _variableString]; // Do any additional setup after loading the view, typically from a nib. } - (void)viewDidUnload { [super viewDidUnload]; // Release any retained subviews of the main view. } @end ``` //class2.h ``` #import @interface ViewController2 : UIViewC…

Accepted Answer

In sender class you can post a notification with an object with something like this:

```
[[NSNotificationCenter defaultCenter] postNotificationName: NOTIFICATION_NAME object: myString];
```

The listener or receiver class has to register for the notification:

```
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(incomingNotification:) name:NOTIFICATION_NAME object:nil];
```

The method incomingNotification is:

```
- (void) incomingNotification:(NSNotification *)notification{
   NSString *theString = [notification object];
   ...
}
```

EDIT

When you post the notification from "ViewController", is "ViewController2" loaded?

pass NSString variable to other class with NSNotification

Solution

Problem