Programming and Problem Solving with Java

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14.Declare a variable of the JButtonclass, instantiate a JButtonobject and assign its

address to the variable, and add the object to the frame’s content pane using the

addmethod.

17.Classes that implement the ActionListenerinterface must have an actionPerformed

method with an ActionEventparameter.

20.There is a default event handler provided for the window closing.

Chapter 8 Programming Warm-Up Exercises

2. a.ButtonHandler action;
   JButton enter;
   JButton quit;
   b.enter = newJButton("Enter");
   quit = newJButton("Quit");
   action = newButtonHandler();
   c. outPane.add(enter);
   outPane.add(quit);
   d.enter.addActionListener(action);
   quit.addActionListener(action);
   e.String name;
   name = event.getActionCommand();
   f. private classButtonHandler implementsActionListener
   {
   public voidactionPerformed(ActionEvent event)
   {
   String name;
   name = event.getActionCommand();
   if(name.equals("Enter"))
   out.add(newJLabel("Enter was pressed."));
   else if(name.equals("Quit"))
   out.add(newJLabel("Quit was pressed."));
   else
   out.add(newJLabel("An unexpected event occurred.")):
   }
   }


3. a.JFrame exampleFrame;
   JLabel exampleLabel;
   JTextField exampleField;
   staticJButton exampleButton;
   container outPane;