Java Programming: Advanced Topics 1 Components and Facilities for Rich Graphical User Interfaces Chapter 7

Java Programming: Advanced Topics 2 Objectives Become familiar with the extensive library of GUI components offered by the Swing API Write code that uses the methods of the javax.swing.JComponent class Learn to add windows, dialog boxes, and panels to a GUI application Learn to add labels, buttons, and check boxes to a GUI application Learn to add menus, toolbars, and actions to a GUI application Learn to add sliders, spinners, progress bars, and scrollbars to a GUI application

Java Programming: Advanced Topics 3 Objectives (Cont.) Learn to add lists and combo boxes to a GUI application Learn to add text-entry components to a GUI application Learn to add file and color choosers to a GUI application Learn to add tables and trees to a GUI application Add printing support to a GUI application using the 2D API Learn how to discover what print facilities are available to an application using the Java Print Service API

Java Programming: Advanced Topics 4 Programming with the JFC To create applets or application that have graphical user interfaces (GUIs), use the Java Foundation Classes (JFC) of the Java platform Support for the development of GUIs for the Java platform is provided by a combination of the AWT and Swing APIs

Java Programming: Advanced Topics 5 Packages of the AWT

Java Programming: Advanced Topics 6 Packages of the AWT (Cont.)

Java Programming: Advanced Topics 7 The Swing Packages

Java Programming: Advanced Topics 8 The Swing Packages (Cont.)

Java Programming: Advanced Topics 9 Swing API Components Windows Dialog boxes Panels Labels Buttons Check Boxes Menus Toolbars Sliders Spinners Progress bars Scrollbars Lists Combo boxes Text-entry components Tables Trees File and color choosers

Java Programming: Advanced Topics 10 JComponent Class The JComponent class is the abstract superclass for all Swing components Methods: –void addxxxListener(xxxListener object ) –void repaint( ) –void repaint ( long msec) –void repaint (int x, int y, int height, int width) –void repaint ( long msec, int x, int y, int height, int width) –void setVisible( boolean b ) –void update( Graphics context )

Java Programming: Advanced Topics 11 Windows, Dialog Boxes, and Panels Containers: components that hold other components Swing provides several top-level container components: –JApplet –JDialog –JFrame –JWindow To add a component to a JApplet, JDialog, JFrame, or JWindow object, call the method getContentPane

Java Programming: Advanced Topics 12 Windows, Dialog Boxes, and Panels (Cont.) An application runs in a JFrame object An applet runs in a JApplet object You build a GUI adding containers and components to the JFrame object of an application or the panel of an applet JDesktopPane, JInternalFrame, JOptionPane, and JPanel are lightweight components that extend JComponent

Java Programming: Advanced Topics 13 Methods of the Container Class The Container class provides several methods for adding and removing components or working with layouts: –void add( Component comp ) –void add( Component comp, Object constraint ) –Component[ ] getComponents() –LayoutManager getLayout() –void remove( Component comp ) –void setLayout( LayoutManager mgr )

Java Programming: Advanced Topics 14 Labels, Buttons, and Check Boxes Labels add text that typically explains the purpose of the other elements of a user interface Buttons and check boxes provide the opportunity to make selections and trigger actions

Java Programming: Advanced Topics 15 AbstractButton and Its Subclasses

Java Programming: Advanced Topics 16 Menus, Toolbars, and Actions To add menus to your GUI, use the classes: –JMenuBar –JMenuItem –Jmenu –JPopupMenu –JRadioButtonMenuItem –JCheckBoxMenuItem Swing provides support for toolbars through the JToolBar class

Java Programming: Advanced Topics 17 Menus, Toolbars, and Actions (Cont.) Swing provides a mechanism, the Action interface, for defining objects that can be put into toolbars and menus Actions that are common to both menus and toolbars can be created as subclasses of AbstractAction to provide a single point of control

Java Programming: Advanced Topics 18 Menus, Toolbars, and Actions (Cont.) To create a main menu for an application, use a JMenuBar object Use the add method to add menus to the menu bar and the setJMenuBar method to add the menu bar to its window For a menu that is associated with a component and pops up when the user clicks a component, create a JPopupMenu object

Java Programming: Advanced Topics 19 Menus, Toolbars, and Actions (Cont.) For every item in a menu, use an instance of JMenuItem or a subclass of JMenuItem To nest menus, use JMenu objects. A JMenu object is a JMenuItem object that is itself a menu For a menu item that is also a check box, use a JCheckBoxMenuItem object For a menu item that is also a radio button, use a JRadioButtonMenuItem object.

Java Programming: Advanced Topics 20 Menu Classes in javax.swing

Java Programming: Advanced Topics 21 Sliders, Spinners, Progress Bars, and Scrollbars JProgressBar, JScrollBar, JSlider, and JSpinner allow users to select or display a value within a bounded range Programs use JProgressBar objects to indicate the progress of a long-running operation Use a JScrollBar object to control the visible contents of a component

Java Programming: Advanced Topics 22 Sliders, Spinners, Progress Bars, and Scrollbars (Cont.) Use a JScrollPane object to display a component with contents that are likely to exceed the available visible area The JScrollPane class adds scrollbars automatically to control scrolling operations Use a JSlider object to allow selection of a value within a bounded range Use a JSpinner object to allow selection of a value within a bounded range from a predetermined list of legal values

Java Programming: Advanced Topics 23 Output of the FontSliderSpinner Class

Java Programming: Advanced Topics 24 Lists and Combo Boxes The JComboBox component is a drop-down list that is useful for lists with a small number of items A JList object displays a list of choices from which it is possible to select one or multiple items JList objects can be contained within JScrollPane and scrolled to view the entire list

Java Programming: Advanced Topics 25 Text-Entry Components A JEditorPane object is a region that is designed to parse and edit specific types of structured text content A JFormattedTextField object is an entry field in which the data that the user enters must meet the specified formatting rules A JPasswordField field can display a single line of text and lets the user enter or edit the text

Java Programming: Advanced Topics 26 Text-Entry Components (Cont.) JTextArea is a region that can contain several lines of text JTextField can display a single line of text and lets the user enter or edit the text A JTextPane object is a region that can contain several lines of text

Java Programming: Advanced Topics 27 TextComponent and Its Subclasses

Java Programming: Advanced Topics 28 Color and File Choosers Swing includes the standard classes JFileChooser and JColorChooser that implement panels and that can be embedded in dialogs or internal frames JColorChooser is a panel that allows users to browse a palette of available colors and select one JFileChooser is a panel that allows users to browse the contents of the file system and select a file to open or a file to save

Java Programming: Advanced Topics 29 Tables and Trees Swing provides two sophisticated controls for structured information: –JTable –JTree The JTable class is best suited for tabular information The JTree class is ideal for hierarchical information

Java Programming: Advanced Topics 30 Output of the JTree Example Class

Java Programming: Advanced Topics 31 The JTable Constructors Table() Table(int rows, int columns ) Table( Object[][] rowData, Object[] columnNames ) Table( Vector rowData, Vector columnNames ) Table( TableModel model ) Table( TableModel model, TableColumnModel tcModel ) Table( TableModel model, TableColumnModel tcModel, ListSelectionModel lsModel )

Java Programming: Advanced Topics 32 The Output of the JTable Class

Java Programming: Advanced Topics 33 Printing with the 2D API The Java 2D API introduced the java.awt.print package to provide printing support on the Java platform The java.awt.print.PrinterJob class provides the control point for displaying print-related dialog boxes, indicating what will print, and actually starting the print job The PageFormat class provides information about the size, orientation, and area available for printing for a page of printed output

Java Programming: Advanced Topics 34 java.awt.print.PrinterJob Methods of the class java.awt.print.PrinterJob: –PageFormat defaultPage( ) –PrintService getPrintService() –PageFormat pageDialog( PageFormat format ) –PageFormat pageDialog( PrintRequestAttributeSet attrs ) –void print() –void print( PrintRequestAttributeSet attrs ) –boolean printDialog() –boolean printDialog( PrintRequestAttributeSet attrs ) –void setPrintable( Printable painter )

Java Programming: Advanced Topics 35 The Page Setup Dialog Box

Java Programming: Advanced Topics 36 Java Print Service API The Java Print Service API can be used for printing text and graphics that are displayed within an application The Java Print Service API is used to handle many flavors of documents, to search and discover print services for handling these document flavors

Java Programming: Advanced Topics 37 Java Print Service API (Cont.) The Doc interface encapsulates the interface for an object that supplies a piece of print data for a print job The DocFlavor class encapsulates the format in which data will be supplied to a DocPrintJob object The javax.print.DocPrintJob interface represents a print job that can print a specified document with a set of job attributes

Java Programming: Advanced Topics 38 Summary The AWT API provides the infrastructure for layout managers, events, event listeners, and basic 2D graphics support The Swing API provides a comprehensive set of GUI components to produce professional applications JComponent is the superclass of all Swing components, and JApplet, JDialog, JFrame, and JWindow are the top-level containers An application runs in a JFrame object, and an applet runs in a JApplet object

Java Programming: Advanced Topics 39 Summary (Cont.) Swing provides classes to support buttons, check boxes, menus, toolbars, sliders, spinners, progress bars, scrollbars, lists, combo boxes, text-entry components Swing includes the standard classes JFileChooser and JColorChooser that implement panels JTable is used for tabular information, and JTree for hierarchical information Print capability can be added to an application by using either the Printing API from the 2D API or by using the Java Print Service API