Populate and bind an NSTableView to multiple array controllers - objective-c

Question

I have an API provided NSArray with a bunch of content objects – we'll call this acquiredFruit – and an empty NSMutableArray called likedFruit.
I've created NSArrayControllers for both arrays and bound my TableView to acquiredFruit.arrangedObjects. The first column of the tableView is bound to arrangedObjects.name and correctly shows all the delicious fruit.
I've created a second column with a checkbox – when the user fills the box I'd like to add the fruit to my likedFruit array. Unchecking the box should remove the fruit object from the likedFruit array.
Essentially I'd like my NSTableView to join between two array controllers. I have a feeling I should be making a single separate controller for this, but I'm unsure how to approach the problem.
I should also mention that I'm aware I could iterate through my array and construct another object with the fields I need, but my goal is to do this by using bindings, if possible.
Thoughts?

Answer 1

I think you should use one array controller.
You can have an attribute on Fruit called liked. Now your "liked" checkbox column is connected to arrangedObjects.liked. Later, when you want to determine the set of all liked fruits, you can query your fruits array:
NSArray * likedFruits = [ allFruitsArray filteredArrayUsingPredicate:[ NSPredicate predicateWithFormat:#"liked = YES"] ] ;
If in another part of your UI you are displaying only liked fruit, you can set your array controller's filterPredicate to the predicate above to get just those fruits.
EDIT: Let's say NSFruit is provided via someone else's API. Let's use the "General Technique for Adding Properties to Someone Else's Class":
#interface NSFruit (Liking)
#property ( nonatomic ) BOOL liked ;
#end
#implementation NSFruit (Liking)
-(BOOL)liked
{
return [ objc_getAssociatedObject( self, "_abliked" ) boolValue ] ;
}
-(void)setLiked:(BOOL)b
{
objc_setAssociatedObject( self, "_abliked", [ NSNumber numberWithBool:b ], OBJC_ASSOCIATION_RETAIN_NONATOMIC ) ;
}
#end
(I've written this same code for like 100 posts recently!)

Answer 2

I'm not at my Xcode computer right now, so i can't test this, but it seems like you don't really need another array controller, but just another array to hold the likedFruits. I think you need to create an array of dictionaries from your acquiredFruits array that would have one key for the fruit name and another key with a bool value for whether the check box is checked --this bool would be bound to your second column. I'm not sure about the next step on how to tell the likedFruit array that it need to add a new fruit -- I think the check box could have an action method that you could use to have the likedFruit array add the object in the row where the check box was clicked.
After Edit:
Here is an example of how to do what I suggested. I take an array of fruits and turn it into an array of dictionaries (called theData) that include a key for the value of your check box (In IB the content array of the array controller is bound to theData, and the columns are bound to Array Controller.arrangedObjects.fruitName and Array Controller.arrangedObjects.isLiked). checkChanged is an IBAction connected to the check box (but note the sender is actually the table view), and I use the value of the check box to determine whether to add a fruit to likedFruits or delete one. I put one more method, connected to a button just to check the values in likedFruits.
#implementation AppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
self.theData = [NSMutableArray array];
self.likedFruit =[NSMutableArray array];
NSArray *acquiredFruits = #[#"Apple",#"Orange",#"Pear",#"Peach"];
for (NSString *aFruit in acquiredFruits) {
NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:aFruit,#"fruitName",[NSNumber numberWithBool:NO],#"isLiked", nil];
[self.theData addObject:[dict mutableCopy]];
}
self.theData = _theData;
// NSLog(#"%#",self.theData);
}
-(IBAction)checkChanged:(NSTableView *)sender { //connected to the button cell in the table view (but sender is the table view)
NSString *theFruit = [[self.controller.arrangedObjects objectAtIndex:sender.clickedRow ] valueForKey:#"fruitName"];
BOOL doWeLikeIt = [[[self.controller.arrangedObjects objectAtIndex:sender.clickedRow] valueForKey:#"isLiked"] boolValue];
if (doWeLikeIt) {
[self.likedFruit addObject:theFruit];
}else{
[self.likedFruit removeObject:theFruit];
}
}
-(IBAction)logLikedFruits:(id)sender {
NSLog(#"%#",self.likedFruit);
}