NSArray losing data in objective-c, Could someone explain why? - iphone

Question

I have an nsarray that when I NSLog it from one of my methods (inside WorkOutList.m) I can see its contents, but when I try to look inside it from a different method inside WorkOutList.m it seems to be empty. I am aware that my memory management needs some work, could anyone help explain whats happening here?
I am using popViewControllerAnimated:YES to return the view from a tableView back to a view controller, but just before I do that I set my array in a method inside WorkOutList. When I NSLog that array from that same method I am returned results, however when i NSLog it from else where it is returned empty.
I have been told that it might be the viewDidLoad method where the array is init, but that the other array in that method customWorkouts still retains its data. So i dunno, any explanation would be really helpful. I want this to work, but I also really want to understand it so I can get on with coding correctly.
Thanks so much!
WorkOutList.h
#import <UIKit/UIKit.h>
#interface WorkOutList : UIViewController {
NSManagedObjectContext *managedObjectContext;
NSMutableArray *customWorkouts;
NSArray *passedWorkout;
}
#property(nonatomic, retain)NSManagedObjectContext *managedObjectContext;
#property(nonatomic, retain)NSMutableArray *customWorkouts;
#property(nonatomic, retain)NSArray *passedWorkout;
-(IBAction)customWorkouts:(id)sender;
-(void)passWorkoutBack:(NSArray *)workout;
#end
WorkOutList.m
#implementation WorkOutList
#synthesize managedObjectContext, customWorkouts, passedWorkout;
- (void)viewDidLoad {
[self setupContext];
NSLog(#"View Did Load");
customWorkouts = [[NSMutableArray alloc] init];
passedWorkout = [[NSArray alloc] init];
[super viewDidLoad];
}
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[self fetchWorkoutList];
NSLog(#"View will Appear");
NSLog(#"Array from View Will Appear : %#", passedWorkout);
}
-(IBAction)customWorkouts:(id)sender{
CoCoachAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
SelectedWorkout *selectedWorkout = [[SelectedWorkout alloc] initWithStyle:UITableViewStyleGrouped];
[selectedWorkout recieveNeededData:customWorkouts];
[appDelegate.practiceNavController pushViewController:selectedWorkout animated:YES];
[selectedWorkout release];
}
-(void)passWorkoutBack:(NSArray *)workout{
passedWorkout = workout;
[passedWorkout retain];
}
- (void)dealloc {
[super dealloc];
}
SelectedWorkout.h
#import <UIKit/UIKit.h>
#interface SelectedWorkout : UITableViewController {
NSMutableArray *workoutListForTable;
}
#property(nonatomic,retain)NSMutableArray *workoutListForTable;
-(void)recieveNeededData:(NSMutableArray *)workoutList;
#end
SelectedWorkout.m(aside from all the stuff to set up the tableView)
#implementation SelectedWorkout
#synthesize workoutListForTable;
-(void)recieveNeededData:(NSMutableArray *)workoutList{
if (workoutListForTable != workoutList) {
workoutListForTable = workoutList;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:YES];
CoCoachAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
WorkOutList *workoutListView = [[WorkOutList alloc]init];
[workoutListView passWorkoutBack:[workoutListForTable objectAtIndex:indexPath.row]];
[appDelegate.practiceNavController popViewControllerAnimated:YES];
}
- (void)dealloc {
[workoutListForTable release];
[super dealloc];
}
NSLog(#"other table : %#", workoutListForTable);
[workoutListForTable retain];
}

Answer 1

In this line:
passedWorkout = [[NSArray alloc] init];
You're creating an immutable array with nothing in it. What do you want it to contain?

Answer 2

It looks to me that although you are initializing your array with or so I assume, since on the other line you are only allocating an empty array.
[self fetchWorkoutList]
You are resetting it here every time:
[workoutListView passWorkoutBack:[workoutListForTable objectAtIndex:indexPath.row]];
As a note here:
-(void)passWorkoutBack:(NSArray *)workout{
passedWorkout = workout;
[passedWorkout retain];
}
You have the property passedWorkout as retain already, however you need to call it on self
-(void)passWorkoutBack:(NSArray *)workout{
self.passedWorkout = workout;
}