guis for applets [email protected] introduction applets and swing/jfc alternatives to swing...
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GUIs for Applets
IntroductionApplets and Swing/JFC
Alternatives to Swing
Look-and-Feel issues
Example applet graphical user interfaces
How do I build a GUI?
Conclusion
GUIs for Applets
Applets and Swing/JFC
Swing is a kit of GUI “widgets” - it provides a simple way to create, position and interact with standard interface components
It is a major part of the Java Foundation Classes (c.f. MFC, Microsoft Foundation Classes)
It is a “lightweight” component library, uses the MVC (model-view-controller) architecture design pattern
Applets may use most Swing componentsFor security reasons some are restricted (which ones?)
GUIs for Applets
Alternatives to Swing
The original GUI system for Java was called the “Abstract Windowing Toolkit” or AWT
NB Swing is based on many of the AWT components, either through compatible methods or through inheritance
AWT is a “heavyweight” component library, uses the widgets built into the underlying OS architecture
It has some OS-specific behaviour and thus some portability problems
GUIs for Applets
Alternatives to Swing
SWT is the Standard Widget Toolkit originally developed by IBM as part of the Eclipse project (see http://www.developer.com/java/other/article.php/2179061)
It is seen a “thin wrapper” over the native GUI of the host OS – it is a “heavyweight” library
It is not OS-specific but was originally designed to run in MS Windows
SWT attempts to use the strengths of the Swing and AWT approaches while staying simple and quick
GUIs for Applets
Examples
Simple visual applet with mouse-sensitive image-based components
Note that the title bar is not settable
This is a Swing-based Japplet running in Win XP
GUIs for Applets
Swing Example
Quite a lot of components in this simple applet
JLabel, JCheckBox, JTextArea, JComboBox, JButton, JRadioButton
This applet will look very similar in any graphical OS
GUIs for Applets
Swing Example
This example shows most of the simple Swing components
The GUI is X-Windows
http://commons.wikimedia.org/ wiki/Image:Gui-widgets.png
GUIs for Applets
SWT platform-specific examples
The Standard Widget Toolkit (SWT) library uses heavyweight components
Tied to the look-and-feel of the host OS
GUIs for Applets
SWT – a familiar example
Eclipse has one of the best-known examples of SWT in action
Looks good and works well
GUIs for Applets
Building a GUI
Choose AWT, Swing (recommended) or SWT
Learn about component types, event handlers and layout options – documentation and examples
Design a user interface and critically evaluate it
Revise and repeat!
For background on development in AWT, with reference to Swing, see “Graphical User Interface (GUI) Fundamentals” (old article)[http://www.wirelessdevnet.com/channels/java/training/javagui.html]
GUIs for Applets
ConclusionThere are varied ways to build GUI applications in
Java AppletsDifferent approaches have different strengths and
weaknessesSwing is often a good choice (widely supported,
flexible, elegant but quite complex)Predefined widgets/components are available for
most tasksDesigning a good interface is hard
GUIs for Applets
Optional Further Reading
Swing article on Wikipedia [http://en.wikipedia.org/wiki/Java_Swing]
Applet article on Wikipedia[http://en.wikipedia.org/wiki/Java_applet]
Standard Widget Toolkit article on Wikipedia[http://en.wikipedia.org/wiki/Standard_Widget_Toolkit]
Swing documentation (Sun)[http://java.sun.com/javase/6/docs/api/index.html]
How to make Applets (Sun)[http://java.sun.com/docs/books/tutorial/uiswing/components/applet.html]