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Class Calculator.ButtonHandler

java.lang.Object
   |
   +----Calculator.ButtonHandler
public class ButtonHandler
extends Object
implements Runnable
This class is the "smarts" for a Calculator. There should be one for each Calculator. Creating it sets up all of the other infrastructure required to handle button presses; it is an interactive control loop and runs asynchronously with the Calculator GUI.

The heart of a ButtonHandler instance is an interactive control loop that operates in an object-oriented polymorphic-dispatch mode: that is, each button pressed is associated with an intelligent ButtonObj(ect), and that button object is asked to handle itself. There's also a single calculator state object that each of the button objects can use.

See Also:
Calculator

Constructor Index

o ButtonHandler(Calculator)
This constructor sets up a button handler control loop and the myriad objects that will actually do the work.

Method Index

o run()
Called by the ButtonHandler's Thread, this is how this object behaves on an ongoing/independent basis.

Constructors

o ButtonHandler 
 public ButtonHandler(Calculator realGUI)
This constructor sets up a button handler control loop and the myriad objects that will actually do the work.

Parameters:
realGUI - The Calculator whose button presses this object is handling.

Methods

o run 
 public void run()
Called by the ButtonHandler's Thread, this is how this object behaves on an ongoing/independent basis. Gets a button, handles it, repeat.

How to handle a button? Ask the associated "smart object" to handle itself! (Typical middle management :o) ).

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