Second calc

Ok, so I changed some stuff around. I added a new float to the calc and renamed result. There are now 2 floats, one called inactiveNumber and another called activeNumber. The active one is the one that will be currently displayed on the calculator/will be the one that is modified when a number button is pressed.

I also added (or tried) the functionality for the buttons but I am unsure how to pass a specific operand with them. I changed the calculate function in calculator to account for the new structure (when the operand changes, the active float is saved to inactive, active is cleared to 0 and the UILabel updates; when the "=" button is hit, the calc uses the previously input operand gotten from the button that was pushed then the UILabel should update accordingly)

Basically I need to make sure that the correct operand is being passed through the selector on the buttons, but I am not sure how to do that. I can only put "changeOperand:" as the selector but can't put in more info?

Also I am not entirely sure that my delegate methods are working in the view controller. I added a new one for "operandDidChange" to let the UILabel know what to do.
Sadly target action is not super convenient for passing around info like that. I would make a methane on the view controller and target that one. Maybe something like

- (void)setOperationAction:(id)sender
{
     UIButton *button = (UIButton *)sender;
     if ([button.title isEqualToString:@"+"]) {
         [self.calculator setOperation:DEVCalculatorOperationAdd];
      }
....
}