How to pass values between 2 NSWindowController - objective-c

Question

I am stuck trying to pass data from one NSWindowController to other one.
I have 2 NSWindowController that has already been instanced and their respective NIB been loaded in screen, in fact firstWindowController load first, get some input from user and do some calculation and save them in several variables and IBOutlets. Upon user action (NSButton) in firstWindowController the secondWindowController load the second Nib window.
Let say:
firstWindowController.h
#class secondWindowController;
#interface firstWindowController : NSWindowController
{
secondWindowController *_secondWindowController;
}
#property long double onedata;
#property (strong) IBOutlet NSTextField *rZab;
#property (strong) IBOutlet NSTextField *xZab;
#end
In firstWindowController.m is the code that instance _secondWindowController, do synthesize in all #property's variables and objects and load the associated nib screen. In the same way, onedata variables and both IBOulets get some values assigned. Omitted for simplicity.
secondWindowController.h
#interface secondeWindowController: NSWindowController
long double newdata;
-(void)getDataFromFirstWC;
#end
secondWindowController.m
#import "firstWindowController.h"
#import "secondWindowController.h"
#import "myAppDelegate.h"
#implementation secondWindowController
-(void)getDataFromFirstWC
{
newdata = 0.0;
newdata = (_firstWindowController.onedata);
// Compilation fails here...
}
#end
This do not compile. The instance of _firstWindowController is not recognized ??.
Use of undeclared identifier '_firstWindowController'
The instance of _firstWindowController has been created in my application delegate already and it is responsible to load the first window nib.
Any help to get this done?. Other answers to more o less similar questions have not help me.

Answer 1

You need to have an instance of your firstWindowController in the secondWindowController. Try this:
in your seconWindowController.h:
#class firstWindowController //<-- add this
#interface secondeWindowController: NSWindowController
{
firstWindowController *fwc; //<-- and this
}
long double newdata;
-(void)getDataFromFirstWC;
#end
in your seconWindowController.m:
#import "firstWindowController.h"
#import "secondWindowController.h"
#import "myAppDelegate.h"
#implementation secondWindowController
-(void)getDataFromFirstWC {
newdata = 0.0;
newdata = (fwc.onedata); //<-- add this and it should work
NSLog(#"newdata is: %f", newdata);
}
#end
As long as I understood your code so far you don't need to create an instance of the secondWindowController in your firstWindowController. Good luck!