Question

I have 3 classes in my project : HeliController, FlightView and ConnectionView.
HeliController stores some connection data which is to be used by both FlightView and ConnectionView.

In both ConnectionView and HeliController I have

// Interface
#import "HeliController.h"
@property (retain) HeliController *heliController;

// Implementation
@synthesize HeliController = _HeliController

The ConnectionView takes care of all connection methods, so this class receives the peripheral I am communication with. From here, I send the peripheral data to be stored in the HeliController (which also is the delegate for the peripheral class):

// ConnectionView.m
self.heliController = [[HeliController alloc] initWithDelegateAndPeripheral:self peripheral:peripheral]; 
// Self will receive callbacks from HeliController and the connected peripheral is stored in the HeliController

// HeliController.m:
- (id)initWithDelegateAndPeripheral:(id<HeliControllerDelegate>)delegate peripheral:(CBPeripheral *)peripheral{

if([super init]){
    self.peripheral = peripheral;
    self.peripheral.delegate = self;
}
return self;

}

Now I can reach the peripheral from ConnectionView with

self.heliController.peripheral

and see that both have addresses on stack:

_heliController HeliController *    0x0017f9e0
_peripheral CBPeripheral *  0x0017e570

From FlightView I also want to reach the peripheral data. I do

self.heliController = [[HeliController alloc] init];

and see in the debugger that self.heliController gets an address on stack

_heliController HeliController *    0x0018ac60

but the peripheral is nil

_peripheral CBPeripheral *  0x00000000

why is this? What am I forgetting? This problem occured when I had to restructure my application, and I can’t figure out what I have done wrong.

Answer 1

My sollution was to send the heliController object to the FlightView when I changed between the views like this:

- (IBAction)changeViewToFlight:(id)sender {

FlightView *vc = [self.storyboard instantiateViewControllerWithIdentifier:@"FlightViewIdentifier"];

// Make sure the heliController object is passed on to the FlightView
vc.heliController = self.heliController;

[self.navigationController pushViewController:vc animated:YES];
}