Manually triggering key-value binding goes like this:
- (void)symbolSelected: (id)sender
{
NSTextField *field;
switch ([sender tag]) {
case 0:
field = stockField1;
break;
case 1:
field = stockField2;
break;
case 2:
field = stockField3;
break;
}
field.stringValue = [sender representedObject];
NSDictionary *bindingInfo = [field infoForBinding: NSValueBinding];
[[bindingInfo valueForKey: NSObservedObjectKey] setValue: field.stringValue
forKeyPath: [bindingInfo valueForKey: NSObservedKeyPathKey]];
}