Chapter 9: Objects and Classes

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2 What is a JavaBean? JavaBean Java JavaBean Java JavaBean

3 JComponent tooltiptext font background foreground doublebuffered border preferredsize minimumsize maximumsize

4 JButton. Swing JButton JButton() JButton(String text) JButton(String text, Icon icon) JButton(Icon icon) Example 9.1: Using Buttons ButtonDemo

5 JLabel. : JLabel() JLabel(String text, int horizontalalignment) JLabel(String text) JLabel(Icon icon) JLabel(Icon icon, int horizontalalignment) Example 9.2: Using Labels LabelDemo

6 JTextField Example 9.3: Using Text Fields add TextFieldDemo

7 JTextArea. JTextArea(int rows, int columns) JTextArea(String s, int rows, int columns)

8 Example 9.4 Using Text Areas. JPanel JFrame DescriptionPanel 1 1 TextAreaDemo -jlblimage -jlbltitle -jtatextdescription +setimageicon +settitle +settextdescription +getminimumsize TextAreaDemo

9 JComboBox. JComboBox() Example 9.5: Using Combo Boxes ComboBoxDemo

10 JList. Example 9.6: Using Lists ListDemo

11 JCheckBox. Example 9.7: Using Check Boxes CheckBoxDemo

12 JRadioButton. Example 9.8: Using Radio Buttons RadioButtonDemo

13 Borders Swing JComponent. Example 9.9: Using Borders BorderDemo

14 Message Dialogs. Example 9.10: Using Message Dialogs DialogDemo

15 Menus Java JMenuBar, JMenu, JMenuItem, JCheckBoxMenuItem, and JRadioButtonMenuItem. Java

16 Example 9.11: Using Menus Objective: Create a user interface that performs arithmetic. The interface contains labels and text fields for Number 1, Number 2, and Result. The Result box displays the result of the arithmetic operation between Number 1 and Number 2. MenuDemo

17 Creating Multiple Windows The following slides show step-by-step how to create an additional window from an application or applet.

18 Creating Additional Windows, Step 1 Step 1: Create a subclass of JFrame (called a SubFrame) that tells the new window what to do. For example, all the GUI application programs extend JFrame and are subclasses of JFrame.

19 Creating Additional Windows, Step 2 Step 2: Create an instance of SubFrame in the application or applet. Example: SubFrame subframe = new SubFrame("SubFrame Title");

20 Creating Additional Windows, Step 3 Step 3: Create a JButton for activating the subframe. add(new JButton("Activate SubFrame"));

21 Creating Additional Windows, Step 4 Step 4: Override the actionperformed() method as follows: public actionperformed(actionevent e) { String actioncommand = e.getactioncommand(); if (e.target instanceof Button) { if ("Activate SubFrame".equals(actionCommand)) { subframe.setvisible(true); } } }

22 Example 9.12 Creating Multiple Windows This example creates a main window with a text area in the scroll pane, and a button named "Show Histogram." When the user clicks the button, a new window appears that displays a histogram to show the occurrence of the letters in the text MultipleWindowsDemo area. Histogram

23 JScrollBar A scroll bar is a control that enables the user to select from a range of values. The scrollbar appears in two styles: horizontal and vertical. Example 9.13: Using Scrollbars ScrollBarDemo

24 Scroll Bar Properties Minimal value Block decrement Block increment Maximal value Bubble Unit decrement Unit increment

25 JScrollPane A scroll pane is a component that supports automatically scrolling without coding. Example 9.14: Using Scroll Panes ScrollPaneDemo

26 Scroll Pane Structures Corner Component Column header Corner Component JViewport Row header Scrollable Component Vertical scroll bars Corner Component Corner Component Horizontal scroll bars

27 JTabbedPane A tabbed pane provides a set of mutually exclusive tabs for accessing multiple components. Example 9.15: Using Tabbed Panes TabbedPaneDemo

(CIP) Web /,. :,2005. 1 ISBN 7 81058 782 X.W............T P393.4 CIP (2004) 118797 Web ( 99 200436) ( http:/ / www.shangdapress.com 66135110) : * 787

Web (CIP) Web /,. :,2005. 1 ISBN 7 81058 782 X.W............T P393.4 CIP (2004) 118797 Web ( 99 200436) ( http:/ / www.shangdapress.com 66135110) : * 787 1092 1/ 16 30.75 748 2005 1 1 2005 1 1 : 1 3 100