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Class Calculator.DotButtonObj

java.lang.Object
   |
   +----Calculator.ButtonObj
           |
           +----Calculator.DotButtonObj
public class DotButtonObj
extends ButtonObj
This class is a smart button object that handles the Calculator's decimal point. Every ButtonHandler should have one.

See Also:
Calculator

Constructor Index

o DotButtonObj(ButtonObj, CalcTextGUI, CalculatorState)
How to make one: Make a ButtonObj (i.e., my superclass) and also remember that zero button.

Method Index

o handleButton()
This method is called by the ButtonHandler whenever the decimal point button is pressed.

Constructors

o DotButtonObj 
 public DotButtonObj(ButtonObj zeroButton,
                     CalcTextGUI gui,
                     CalculatorState stateObj)
How to make one: Make a ButtonObj (i.e., my superclass) and also remember that zero button.

Parameters:
zeroButton - The zero ButtonObj for this calculator.
gui - The CalcTextGUI to keep track of.
stateObj - The CalculatorState to keep track of.

Methods

o handleButton 
 public void handleButton()
This method is called by the ButtonHandler whenever the decimal point button is pressed.

How to handle (my button) being pressed? If we're already reading a number, add the decimal point to the text and have the state remember. If we're not reading a number (e.g., we just saw an operation), pretend that the 0 was pressed first.

Overrides:
handleButton in class ButtonObj
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