Calculator Controls

The main number-and-operation workflow is complete. Now you will make the smaller controls useful.

These controls are good examples of application logic because each one changes state in a different way:

• Clear resets the whole calculator.
• Backspace removes the last entered character.
• Percentage transforms the current value.
• Sign toggle changes the current value between positive and negative.

You will implement each behavior inside Calculator, then connect the prepared controls through the same event pipeline.