Chapter 10 GUI1 例 : LunarPhases, 月亮盈亏 (JB demo) 如何使用 Compound Bounder 如何使用 Combo Boxes 如何使用 Loading Multiple Images

Chapter 10 GUI2 使用多屏 (Panel) 来分组图形组件 // Create the phase selection and display panels. selectPanel = new JPanel(); displayPanel = new JPanel(); // Add various widgets to the subpanels. addWidgets();

Chapter 10 GUI3 // Create the main panel to contain the two subpanels. mainPanel = new JPanel(); mainPanel.setLayout(new GridLayout(2,1,5,5)); // (rows, cols, hgap, vgap) mainPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5)); // Add the select and display panels to the main panel. mainPanel.add(selectPanel); mainPanel.add(displayPanel); Compound Boarder

Chapter 10 GUI4 // Add border around the select panel selectPanel.setBorder(BorderFactory.createCompoundBorder( BorderFactory.createTitledBorder("Select Phase"), BorderFactory.createEmptyBorder(5,5,5,5))); Combo Boxes

Chapter 10 GUI5 JComboBox phaseChoices = null;... // Create combo box with lunar phase choices String[ ] phases = { "New", "Waxing Crescent", "First Quarter", "Waxing Gibbous", "Full", "Waning Gibbous", "Third Quarter", "Waning Crescent" }; phaseChoices = new JComboBox(phases); phaseChoices.setSelectedIndex(START_INDEX); Handling Events on a Combo Box phaseChoices.addActionListener(this);...

Chapter 10 GUI6 public void actionPerformed(ActionEvent event) { if ("comboBoxChanged".equals(event.getActionCommand())) { // update the icon to display the new phase phaseIconLabel.setIcon( images[phaseChoices.getSelectedIndex()]); } Multiple Images final static int NUM_IMAGES = 8; final static int START_INDEX = 3; ImageIcon[ ] images = new ImageIcon[NUM_IMAGES];...

Chapter 10 GUI7 // Create the widgets to select and display the phases of the moon. private void addWidgets() { // Get the images and put them into an array of ImageIcon. for (int i = 0; i < NUM_IMAGES; i++) { String imageName = "images/image" + i + ".jpg"; URL iconURL = ClassLoader.getSystemResource(imageName); ImageIcon icon = new ImageIcon(iconURL); images[i] = icon; } 注 : getSystemResource 会搜索 classpath 中的路径去获取指定图象 例 : VoteDialog 怎样使用 Radio Buttons 怎样使用 Dialogs

Chapter 10 GUI8 怎样使用 Radio Buttons 怎样使用 Dialogs

Chapter 10 GUI9 Radio Buttons final int numButtons = 4; JRadioButton[] radioButtons = new JRadioButton[numButtons]; final ButtonGroup group = new ButtonGroup();... final String defaultMessageCommand = "default"; final String yesNoCommand = "yesno"; final String yeahNahCommand = "yeahnah";

Chapter 10 GUI10 final String yncCommand = "ync“; radioButtons[0] = new JRadioButton(" Candidate 1: Sparky the Dog "); radioButtons[0].setActionCommand(defaultMessageCommand); radioButtons[1] = new JRadioButton(" Candidate 2: Shady Sadie "); radioButtons[1].setActionCommand(yesNoCommand);

Chapter 10 GUI11 radioButtons[2] = new JRadioButton(" Candidate 3: R.I.P. McDaniels "); radioButtons[2].setActionCommand(yeahNahCommand); radioButtons[3] = new JRadioButton(" Candidate 4: Duke the Java TM Platform Mascot "); radioButtons[3].setActionCommand(yncCommand); for (int i = 0; i < numButtons; i++) { group.add(radioButtons[i]); } // Select the first button by default. radioButtons[0].setSelected(true);

Chapter 10 GUI12 Dialogs 1.showMessageDialog –Component parentComponent –Object message

Chapter 10 GUI13 2.showOptionDialog –Component parentComponent –Object message –String title: title of the dialog –int optionType –int messageType –Icon icon: custom icon –Object[] options –Object initialValue

Chapter 10 GUI14 Getting User Input from a Dialog // yes/no dialog } else if (command == yesNoCommand) { int n = JOptionPane.showConfirmDialog( frame, "This candidate is a convicted felon.\n Do you still want to vote for her?", "A Follow-up Question", JOptionPane.YES_NO_OPTION); if (n == JOptionPane.YES_OPTION) { setLabel("OK. Keep an eye on your wallet."); } else if (n == JOptionPane.NO_OPTION) { setLabel("Whew! Good choice."); } else { setLabel("It is your civic duty to cast your vote."); }

Chapter 10 GUI15 图形组件的布局管理 – 五种不同布局管理选项的效果

Chapter 10 GUI16 1.BorderLayout –A BorderLayout has five areas available to hold components: north, south, east, west, and center. All extra space is placed in the center area 例 : Panel p = new Panel(); p.setLayout(new BorderLayout()); p.add(new Button("Okay"), BorderLayout.SOUTH); 2.BoxLayout –The BoxLayout class puts components in a single row or column. This class respects the components' requested maximum sizes and also lets you align components. 例 : // Lay out the label and scroll pane from top to bottom. JPanel listPane = new JPanel(); listPane.setLayout(new BoxLayout(listPane, BoxLayout.Y_AXIS));

Chapter 10 GUI17 3. FlowLayout –FlowLayout is the default layout manager for every JPanel. This layout manager simply lays out components from left to right, starting new rows, if necessary 4.GridLayout –GridLayout simply makes a bunch of components equal in size and displays them in the requested number of rows and columns 例 : public class ButtonGrid extends Applet { public void init() { setLayout(new GridLayout(3,2)); add(new Button("1")); add(new Button("2")); add(new Button("3")); add(new Button("4")); add(new Button("5")); add(new Button("6")); }

Chapter 10 GUI18 5.GridBagLayout –GridBagLayout is the most sophisticated, flexible layout manager the Java platform provides. This layout manager aligns components by placing them within a grid of cells, allowing some components to span more than one cell. The rows in the grid aren't necessarily all the same height; similarly, grid columns can have different widths 关于使用菜单的有关问题 菜单以节省空间的方式给用户提供多种选择 ( MenuLookDemo.java )

Chapter 10 GUI19 菜单图形组件类的层次结构

Chapter 10 GUI20 创建一个菜单 // in the constructor for a JFrame subclass: JMenuBar menuBar; JMenu menu, submenu; JMenuItem menuItem; JCheckBoxMenuItem cbMenuItem; JRadioButtonMenuItem rbMenuItem;... //Create the menu bar. menuBar = new JMenuBar(); setJMenuBar(menuBar); //Build the first menu. menu = new JMenu("A Menu"); menu.setMnemonic(KeyEvent.VK_A); menuBar.add(menu);

Chapter 10 GUI21 // a group of JMenuItems menuItem = new JMenuItem("A text-only menu item", KeyEvent.VK_T); menuItem.setAccelerator( KeyStroke.getKeyStroke( KeyEvent.VK_1,ActionEvent.ALT_MASK)); menu.add(menuItem); menuItem = new JMenuItem( "Both text and icon", new ImageIcon("images/middle.gif")); menuItem.setMnemonic(KeyEvent.VK_B); menu.add(menuItem); menuItem = new JMenuItem(new ImageIcon("images/middle.gif")); menuItem.setMnemonic(KeyEvent.VK_D); menu.add(menuItem);

Chapter 10 GUI22 //a group of radio button menu items menu.addSeparator(); ButtonGroup group = new ButtonGroup(); rbMenuItem = new JRadioButtonMenuItem( "A radio button menu item"); rbMenuItem.setSelected(true); rbMenuItem.setMnemonic(KeyEvent.VK_R); group.add(rbMenuItem); menu.add(rbMenuItem); rbMenuItem = new JRadioButtonMenuItem("Another one"); rbMenuItem.setMnemonic(KeyEvent.VK_O); group.add(rbMenuItem); menu.add(rbMenuItem);

Chapter 10 GUI23 //a group of check box menu items menu.addSeparator(); cbMenuItem = new JCheckBoxMenuItem("A check box menu item"); cbMenuItem.setMnemonic(KeyEvent.VK_C); menu.add(cbMenuItem); cbMenuItem = new JCheckBoxMenuItem("Another one"); cbMenuItem.setMnemonic(KeyEvent.VK_H); menu.add(cbMenuItem); //a submenu menu.addSeparator(); submenu = new JMenu("A submenu"); submenu.setMnemonic(KeyEvent.VK_S); menuItem = new JMenuItem("An item in the submenu"); menuItem.setAccelerator(KeyStroke.getKeyStroke( KeyEvent.VK_2, ActionEvent.ALT_MASK)); submenu.add(menuItem);

Chapter 10 GUI24 menuItem = new JMenuItem("Another item"); submenu.add(menuItem); menu.add(submenu); //Build second menu in the menu bar. menu = new JMenu("Another Menu"); menu.setMnemonic(KeyEvent.VK_N); menuBar.add(menu); 处理来自菜单的事件 (MenuDemo.java) – 向 JMenuItem 对象注册以获取它的 Action 事件 – 向 JRadioButtonMenuItem 对象注册以获取它的 Action 或 Item 事 件 – 向 CheckBoxMenuItem 对象注册以获取它的 Item 事件

Chapter 10 GUI25 // JB demo public class MenuDemo extends JFrame implements ActionListener, ItemListener { public MenuDemo() { //...for each JMenuItem instance: menuItem.addActionListener(this);... //for each JRadioButtonMenuItem: rbMenuItem.addActionListener(this);... //for each JCheckBoxMenuItem: cbMenuItem.addItemListener(this);... }

Chapter 10 GUI26 public void actionPerformed(ActionEvent e) { JMenuItem source = (JMenuItem)(e.getSource()); String s = "Action event detected." + newline + " Event source: " + source.getText() + " (an instance of " + getClassName(source) + ")"; output.append(s + newline); } public void itemStateChanged(ItemEvent e) { //...Get information from the item event... //...Display it in the text area... }

Chapter 10 GUI27 文本图形部件的使用 1.Text Controls – 单行文本输入和编辑 2.Plain Text Controls – 任意行文本输入和编辑, 单字体 3.Styled Text Controls – 任意行文本输入和编辑, 多字体, 图形, 声音

Chapter 10 GUI28

Chapter 10 GUI29 1.An Example of Using a Text Field JTextField textField = new JTextField(10); textField.setActionCommand(textFieldString); textField.addActionListener(this); … public void actionPerformed(ActionEvent e) { String prefix = "You typed \""; if (e.getActionCommand().equals(textFieldString)) { JTextField source = (JTextField)e.getSource(); actionLabel.setText(prefix + source.getText() + "\""); } else { JPasswordField source = (JPasswordField)e.getSource(); actionLabel.setText(prefix + new String(source.getPassword()) + "\""); }

Chapter 10 GUI30 2.An Example of Using a Password Field JPasswordField passwordField = new JPasswordField(10); passwordField.setActionCommand(passwordFieldString); passwordField.addActionListener(this); … 3.An Example of Using a Text Area JTextArea textArea = new JTextArea( "This is an editable JTextArea " + "that has been initialized with the setText method. " + "A text area is a \"plain\" text component, " + "which means that although it can display text " + "in any font, all of the text is in the same font." ); textArea.setFont(new Font("Serif", Font.ITALIC, 16)); textArea.setLineWrap(true); textArea.setWrapStyleWord(true);

Chapter 10 GUI31 给 JTextArea 增加上下滚动功能 (JScrollPane) JScrollPane areaScrollPane = new JScrollPane(textArea); areaScrollPane.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_ALWAYS); areaScrollPane.setPreferredSize(new Dimension(250, 250)); areaScrollPane.setBorder(...create border...); 完整的程序清单 : TextSamplerDemo.java (JB demo)