SWING OVERVIEW
- The basic GUI components are as follows
- JLabel – An area where uneditable text or icons can be displayed.
- JTextField – An area in which the use inputs data from the key board.
- JButton – An area that triggers an event when clicked
- JCheckBox – A GUI component that is either selected or not selected
- JComboBox – A drop-down list of items from which the user can make a selection by clicking an item in the list or possibly by typing into the box
- JList An area where a list of items is displayed from which the user can make a selection by clicking once on any element in the list. Double clicking an element in the list generates an action event. Multiple elements can be selected
- JPanel - A container in which components can be placed
· The classes that create the GUI components above are part of the SWING API which is contained in the package javax.swing. Most swing components are manipulated and diplayed entirely in Java so they are purely Java components as opposed to AWT components which rely on the system that they are running on.
· Swing components are considered lightweight components because they are not tied to the operating system on which they are running as opposed to AWT components which are considered heavyweight components.
· Much of each GUI components’s functionality is derived from the classes
java.lang.Object
java.awt.Component
java.awt.Container
javax.swing.Jcomponent
- Class Component defines the common attributes and behaviors of all subclasses of Component. Most GUI components extend class Component directly or indirectly. It is important to understand the class Component because much of the functionality of subclasses is inherited from Component.
- Class JComponent is the superclass to most Swing components. This class defines the common attributes and behaviors of all subclasses of JComponent.
Swing components of the subclass JComponent have many features including:
1. A pluggable look and feel than can be used to customize the look and feel when the program executes on different platforms.
2. Shortcut keys for direct access to GUI components through the keyboard
3. Common event-handling capabilities for cases where several GUI components initiate the same actions in a program.
4. Brief descriptions of a GUI component’s purpose(TOOL TIPS) that are displayed when the mouse cursor is positioned over the component for a short time.
5. Support for assistive technologies such as Braille screen readers for blind people
6. Support for user interface localization
