How to associate a combobox value with an AppDelegate with a ViewController?

Question

I am trying to get an array from AppDelegate in my ViewController, every time I try to connect to Xcode, it only allows me to access ViewController values, not AppDelegate.

in the following code, I can use two different methods, I show both of them.

• I can just bind combobox to serialpPortManager.availablePorts array
• I can grab the array and insert it into another array so the ViewController sees the array from AppDelegate and then binds the array to combobox

I would like to do this in the first way, but cannot connect it to Xcode.

Appdelegate.h

@interface AppDelegate : NSObject{}

@property (nonatomic, strong) ORSSerialPortManager *serialPortManager;
@property(nonatomic, retain) NSArray *availPorts;

AppDelegate.m

self.serialPortManager = [ORSSerialPortManager sharedSerialPortManager];

ORSSerialPortManager *portManager = [ORSSerialPortManager sharedSerialPortManager];
availPorts = portManager.availablePorts;

ViewController.m

AppDelegate *appDelegate = (AppDelegate*)[[NSApplication sharedApplication]delegate];
NSString * result = [appDelegate.availPorts description];

combobox appDelegate, , ViewController? Xcode, appDelegate?