Curious about NSButtonCell state

Question

I have a NSTableView with an NSTableColumn with an NSButtonCell (a checkbox) inside it, which generates a new instance of NSButtonCell each time a row is added, which I configured in IB. However, I'm curious why in the following chunk of code the second NSLog returns 0.

NSLog(@"%ld", (long)[[self.tableView preparedCellAtColumn:0 row:0]state]);
[[self.tableView preparedCellAtColumn:0 row:0]setState:1];
NSLog(@"%ld", (long)[[self.tableView preparedCellAtColumn:0 row:0]state]);

The fact that it returns 0 means that I am sending a message to an instance of NSButtonCell, right? So why doesn't setState: change the return value of the second NSLog?

Answer 1

If it was receiving nil it would also print 0, I would suggest trying this

NSLog(@"cell:%@", [self.tableView preparedCellAtColumn:0 row:0])

to ensure you are actually getting a valid cell object from the table view.

Where are you calling that code from? After the table is already being displayed? During initialisation?

If the former then there should be a cell available, if the latter then it may not have been created or reallocated from the pool yet.

Try the NSLog command above to ensure you are actually getting a cell back and not nil from the table view.