import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.border.*; /** DemoButtons - program to demonstrate the thee basic types of * buttons: push buttons, checkboxes, and radio buttons.

* * Each button is configured to support keyboard accessibility using * the setMnemonic method. The argument to the * setMnemonic method is a char -- the character * used to 'press' the button using the keyboard, typically by * pressing ALT-char. The character should be one of the characters in the * button's label (e.g., 'B' for the Bold button). It will * appear underlined in the button.

* * To ensure platform independence and compatibility with future releases * of Java, express the character argument to setMnemonic * as VK_?, where '?' is the desired character. See the * KeyEvent API specfication for a complete list of VK (virtual * key) assignments.

* * Screen snap:
*

* * @see source code * @author Scott MacKenzie, 2003 */ public class DemoButtons { public static void main(String[] args) { // use look and feel for my system (Win32) try { UIManager.setLookAndFeel( UIManager.getSystemLookAndFeelClassName()); } catch (Exception e) {} DemoButtonsFrame frame = new DemoButtonsFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setTitle("DemoButtons"); frame.pack(); frame.show(); } } class DemoButtonsFrame extends JFrame implements ActionListener, ItemListener { private JTextField message; private JButton exitButton; private JButton restoreButton; private JCheckBox italicCheckBox; private JCheckBox boldCheckBox; private JRadioButton smallButton; private JRadioButton mediumButton; private JRadioButton largeButton; private JToggleButton showHideButton; final Color FOREGROUND = Color.blue; final Color BACKGROUND = Color.pink; final int SMALL = 12; final int MEDIUM = 24; final int LARGE = 48; final Font DEFAULT_FONT = new Font("Serif", Font.PLAIN, MEDIUM); private int fontSize; private int fontStyle; public DemoButtonsFrame() { fontStyle = Font.PLAIN; fontSize = MEDIUM; // ---------------------------------- // construct and configure components // ---------------------------------- message = new JTextField("Hello Java World"); message.setFont(DEFAULT_FONT); message.setEditable(false); message.setBackground(BACKGROUND); message.setForeground(FOREGROUND); message.setHorizontalAlignment(SwingConstants.CENTER); message.setPreferredSize(new Dimension(400, 150)); restoreButton = new JButton("Restore"); exitButton = new JButton("Exit"); italicCheckBox = new JCheckBox("Italic"); boldCheckBox = new JCheckBox("Bold"); smallButton = new JRadioButton("Small"); mediumButton = new JRadioButton("Medium"); largeButton = new JRadioButton("Large"); mediumButton.setSelected(true); showHideButton = new JToggleButton("Hide"); // set up mnemonics for keyboard accessibility restoreButton.setMnemonic(KeyEvent.VK_R); exitButton.setMnemonic(KeyEvent.VK_E); italicCheckBox.setMnemonic(KeyEvent.VK_I); boldCheckBox.setMnemonic(KeyEvent.VK_B); smallButton.setMnemonic(KeyEvent.VK_S); mediumButton.setMnemonic(KeyEvent.VK_M); largeButton.setMnemonic(KeyEvent.VK_L); showHideButton.setMnemonic(KeyEvent.VK_H); // add radio buttons to button group ButtonGroup sizeGroup = new ButtonGroup(); sizeGroup.add(smallButton); sizeGroup.add(mediumButton); sizeGroup.add(largeButton); // ------------- // add listeners // ------------- restoreButton.addActionListener(this); exitButton.addActionListener(this); italicCheckBox.addItemListener(this); boldCheckBox.addItemListener(this); smallButton.addActionListener(this); mediumButton.addActionListener(this); largeButton.addActionListener(this); showHideButton.addActionListener(this); // ----------------- // layout components // ----------------- // add components to panels JPanel commandPanel = new JPanel(); commandPanel.setLayout(new GridLayout(2, 1)); commandPanel.add(restoreButton); commandPanel.add(exitButton); commandPanel.setBorder(new TitledBorder(new EtchedBorder(), "Commands")); JPanel sizeGroupPanel = new JPanel(); sizeGroupPanel.setLayout(new GridLayout(3, 1)); sizeGroupPanel.add(smallButton); sizeGroupPanel.add(mediumButton); sizeGroupPanel.add(largeButton); sizeGroupPanel.setBorder(new TitledBorder(new EtchedBorder(), "Size")); JPanel styleGroupPanel = new JPanel(); styleGroupPanel.setLayout(new GridLayout(2, 1)); styleGroupPanel.add(italicCheckBox); styleGroupPanel.add(boldCheckBox); styleGroupPanel.setBorder(new TitledBorder(new EtchedBorder(), "Style")); JPanel showHidePanel = new JPanel(); showHidePanel.setLayout(new GridLayout(2, 1)); showHidePanel.add(showHideButton); showHidePanel.setBorder(new TitledBorder(new EtchedBorder(), "View")); // arrange panels JPanel southPanel = new JPanel(); southPanel.setLayout(new GridLayout(1, 4)); southPanel.add(commandPanel); southPanel.add(sizeGroupPanel); southPanel.add(styleGroupPanel); southPanel.add(showHidePanel); JPanel contentPane = new JPanel(); contentPane.setLayout(new BorderLayout()); contentPane.add(message, "Center"); contentPane.add(southPanel, "South"); contentPane.setBorder(BorderFactory.createEmptyBorder(30, 30, 30, 30)); // make panel this JFrame's content pane this.setContentPane(contentPane); } // ------------------------------- // implement ActionListener method // ------------------------------- public void actionPerformed(ActionEvent ae) { // for in-class demo... //System.out.println(ae.paramString()); Object source = ae.getSource(); // 'Command' - check if a command button was pressed if (source == restoreButton) { fontSize = MEDIUM; fontStyle = Font.PLAIN; mediumButton.setSelected(true); italicCheckBox.setSelected(false); boldCheckBox.setSelected(false); showHideButton.setText("Hide"); showHideButton.setSelected(false); message.setForeground(FOREGROUND); } else if (source == exitButton) System.exit(0); // 'Size' - check if a size radio button was pressed else if (source == smallButton) fontSize = SMALL; else if (source == mediumButton) fontSize = MEDIUM; else if (source == largeButton) fontSize = LARGE; // 'Show/Hide' - check if show/hide button was pressed else if (source == showHideButton) { if (ae.getActionCommand().equals("Show")) { message.setForeground(FOREGROUND); showHideButton.setText("Hide"); } else if (ae.getActionCommand().equals("Hide")) { message.setForeground(BACKGROUND); showHideButton.setText("Show"); } } // update message size and style message.setFont(new Font("Serif", fontStyle, fontSize)); } // ----------------------------- // implement ItemListener method // ----------------------------- public void itemStateChanged(ItemEvent ie) { Object source = ie.getSource(); // 'Style' - check if the font style was change via a checkbox if (source == italicCheckBox) if (italicCheckBox.isSelected()) fontStyle = fontStyle | Font.ITALIC; // turn italic on else fontStyle = fontStyle & ~Font.ITALIC; // turn italic off else if (source == boldCheckBox) if (boldCheckBox.isSelected()) fontStyle = fontStyle | Font.BOLD; // turn bold on else fontStyle = fontStyle & ~Font.BOLD; // turn bold off // update message size and style message.setFont(new Font("Serif", fontStyle, fontSize)); } }