I dont understand why i am passing nil through the segue way - ios

Question

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([segue.identifier isEqualToString:#"CatagoryToSetDetail"]){
BYFSetsDetailViewController *controller = (BYFSetsDetailViewController *)segue.destinationViewController;
controller.workOut.catagory = catagory.text;
controller.workOut.excercise = excercize.text;
NSLog(#"passing the values %# \n and %# \n ",controller.workOut.catagory,controller.workOut.excercise);
}
for some reason controller.workOut.category is nil and i dont know how to fix it.
here is how i instantiated it in view did load
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
self.workOut = [[BYFWorkOut alloc]init];
NSLog(#"recieved values %# \n and %# \n ",_workOut.catagory,_workOut.excercise);
}
Thank you any help would be appreciated

Answer 1

prepareForSegue performed before viewDidLoad and yours workOut is nil when you tries assign category and excersize
Solution 1:
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([segue.identifier isEqualToString:#"CatagoryToSetDetail"]){
BYFSetsDetailViewController *controller = (BYFSetsDetailViewController *)segue.destinationViewController;
controller.workOut.catagory = catagory.text;
controller.workOut.excercise = excercize.text;
NSLog(#"passing the values %# \n and %# \n ",controller.workOut.catagory,controller.workOut.excercise);
}
in BYFSetsDetailViewController:
#implementation BYFSetsDetailViewController
#synthesyze workOut = _workOut;
- (id) initWithCoder:(NSCoder*) encoder
{
self = [super initWithCoder:encoder];
if (self)
{
_workOut = [[BYFWorkOut alloc] init];
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
NSLog(#"recieved values %# \n and %# \n ",_workOut.catagory,_workOut.excercise);
}
Solution 2:
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([segue.identifier isEqualToString:#"CatagoryToSetDetail"]){
BYFSetsDetailViewController *controller = (BYFSetsDetailViewController *)segue.destinationViewController;
controller.workOut = [[BYFWorkOut alloc]init];
controller.workOut.catagory = catagory.text;
controller.workOut.excercise = excercize.text;
NSLog(#"passing the values %# \n and %# \n ",controller.workOut.catagory,controller.workOut.excercise);
}
in BYFSetsDetailViewController:
#implementation BYFSetsDetailViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
NSLog(#"recieved values %# \n and %# \n ",_workOut.catagory,_workOut.excercise);
}

Answer 2

Have you checked that category.text and exercise.text are not nil? - as those are the values you're passing to the destinationViewController in this method.
Also, where have you instantiated catagory.text and excercize.text ?
Edit
It looks like your custom object workOut has not been instantiated correctly. Do this in your init or viewDidLoad method of BYFSetsDetailViewController
Edit 2
Okay I got it work like this (Not sure why, maybe someone can explain more)
In your BYFSetsDetailViewController make a public property of NSString (I assume, workOut is an NSString?)
Then in your prepareForSegue method do this:
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([segue.identifier isEqualToString:#"CatagoryToSetDetail"]){
BYFSetsDetailViewController *controller = (BYFSetsDetailViewController *)segue.destinationViewController;
controller.myString = catagory.text;
controller.myString2 = excercize.text;
NSLog(#"passing the values %# \n and %# \n ",controller.workOut.catagory,controller.workOut.excercise);
}
Declare your strings like this: #property (copy, nonatomic) NSString *myString
Then in your viewDidLoad method of BYFSetsDetailViewController
Do this:
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
self.workOut = [[BYFWorkOut alloc]init];
self.workOut.catagory = self.myString;
self.workOut.excercize = self.myString2;
NSLog(#"recieved values %# \n and %# \n ",_workOut.catagory,_workOut.excercise);
}
This should solve your issue.
Edit 3
From Cy-4AH's answer - do this in your prepareForSegue
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([segue.identifier isEqualToString:#"CatagoryToSetDetail"]){
BYFSetsDetailViewController *controller = (BYFSetsDetailViewController *)segue.destinationViewController;
controller.workOut = [[BYFWorkOut alloc]init];
controller.workOut.catagory = catagory.text;
controller.workOut.excercise = excercize.text;
NSLog(#"passing the values %# \n and %# \n ",controller.workOut.catagory,controller.workOut.excercise);
Remember to import BYFWorkOut in this viewController at the top of the file.