Java How to Program Fourth Edition - DCC

904 Files and Streams Chapter 16
defined at lines 34–75. Methods getFieldValues (lines 116–124), setField-
Values (lines 104–113) and clearFields (lines 96–100) manipulate the text of the
JTextFields. Methods getFields (lines 90–93), getDoTask1Button (lines 78–
81) and getDoTask2Button (lines 84–87) return individual GUI components, so that a
client program can add ActionListeners (for example).
1 // Fig. 16.4: BankUI.java
2 // A reusable GUI for the examples in this chapter.
3 package com.deitel.jhtp4.ch16;
4
5 // Java core packages
6 import java.awt.*;
7
8 // Java extension packages
9 import javax.swing.*;
10
11 public class BankUI extends JPanel {
12
13 // label text for GUI
14 protected final static String names[] = { "Account number",
15 "First name", "Last name", "Balance",
16 "Transaction Amount" };
17
18 // GUI components; protected for future subclass access
19 protected JLabel labels[];
20 protected JTextField fields[];
21 protected JButton doTask1, doTask2;
22 protected JPanel innerPanelCenter, innerPanelSouth;
23
24 // number of text fields in GUI
25 protected int size;
26
27 // constants representing text fields in GUI
28 public static final int ACCOUNT = 0, FIRSTNAME = 1,
29 LASTNAME = 2, BALANCE = 3, TRANSACTION = 4;
30
31 // Set up GUI. Constructor argument of 4 creates four rows
32 // of GUI components. Constructor argument of 5 (used in a
33 // later program) creates five rows of GUI components.
34 public BankUI( int mySize )
35 {
36 size = mySize;
37 labels = new JLabel[ size ];
38 fields = new JTextField[ size ];
39
40 // create labels
41 for ( int count = 0; count < labels.length; count++ )
42 labels[ count ] = new JLabel( names[ count ] );
43
44 // create text fields
45 for ( int count = 0; count < fields.length; count++ )
46 fields[ count ] = new JTextField();
Fig. Fig. 16.4 16.4 BankUI contains a reusable GUI for several programs (part 1 of 3).