In this magercise you will install the Swing package and take a tour
of the SwingSet demonstration. Swing is a new set of user interface
components based on the JavaTM
1.1.2+ Abstract Window Toolkit (AWT). The new components are written
entirely using the Java® 2 platform and are part of the JavaTM
Foundation Classes (JFC). After you have installed Swing, the magercise
will introduce and demonstrate the various Swing components.
If you are using the Java® 2 platform, you do not need to download the
Swing classes as they are part of the JavaTM
Development Kit (JDK). You can skip the first couple steps of the exercise.
Magercise 1 Prerequisites
None.
Tasks:
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Download the latest version of the Swing early access release from
Sun.
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Installation requires you to uncompress/untar or unzip the file acquired.
Do not extract the class files from the
*.jar files that are
within the Swing download.
Before running the demonstration, take a look at the online Swing
documentation, and bookmark it. Along with information about Swing,
the online JavaDoc API material is here. You need to open and bookmark
the file:
SwingInstallationDirectory/doc/api/packages.html .
After bookmarking the page, you can browse through the documentation of
the API material.
To run the demonstration, from a command shell with JDK 1.1.x, you need
to setup some environment variables:
For Solaris:
setenv JDKHOME JDKInsallationDirectory
cd SwingInstallationDirectory
cd examples
cd SwingSet
runnit
For Windows 95/NT:
This assumes the JDK is installed in c:\jdk1.1.7
and Swing is located in c:\swing-1.1.
set JDKHOME=C:\jdk1.1.7
set CLASSPATH=%JDKHOME%\lib\classes.zip
set PATH=%JDKHOME%\bin;%PATH%
set SWINGHOME=C:\swing-1.1
cd C:\swing-1.1
cd examples
cd SwingSet
runnit
For Java 2 users:
The SwingSet demo comes with the Java® 2 platform. As long as you are
set up to run the runtime environment, you just need to start the demo.
cd JDKInsallationDirectory
cd demo
cd jfc
cd SwingSet
java SwingSet
This brings up the initial SwingSet demonstration screen.
This magercise does not create a program, but executes Swing's
SwingSet demo. When first started, it will look something like:
Note: Clicking on the image will bring-up a larger
version of the image.
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To demonstrate some of the familiar, select the Buttons tab. This shows
three of the button types supported by Swing: Text Buttons, Image Buttons,
and Rollover Image Buttons.
Notice that the text buttons have an accelerator key. If you select
ALT-accelerator key, the button becomes activated. This is part of
the added keyboard control support in Swing.
For the image buttons: They exist in Swing. If you select the
different image buttons, you'll notice that the second and third buttons
show a green arrow image when depressed, while the first doesn't. This
demonstrates some of the different behavior you can provide. Also, if
you select the Enabled toggled on the right, so that it is unchecked,
this demonstrates the different disabled features you can use.
For the rollover image buttons: When you move the mouse over each button
the image changes. Also, if you change the Text Position by moving the
ball around on the upper right, you can move the text relative to the
image location. The Content Alignment tells the image/text where to go
when additional space is available, so select the 10 toggle, and then
relocate the content. (This is more discernable with components other
than buttons).
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For the RadioButtons, and Checkboxes tabs: The key differences between AWT
and Swing is there is no
CheckboxGroup object. The components
are separate objects. There is however a ButtonGroup object
to group radio buttons together. Another difference between AWT and Swing
is that you can use an image as the toggle object, instead of a checkbox.
As the screens show, this can create some interesting interfaces. The
ToggleButtons tab shows a third kind of toggle control.
For the Labels tab: The only things new there are that a label can have
an image on it and a keyboard accelerator for a label can move the input
focus to an associated component.
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Some of the new components introduced by Swing can be found under the
Borders, ComboBox, TableView, BorderedPane, SplitPane and ToolTips tabs.
The cow shown under the ToolTips tab acts like an image map, where certain
areas of the cow show different tool tips. Rest your mouse and see the
different ones. Be sure to find the area that has "Got Milk?"
as its tool tip.
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Selecting the Internal Frame tab shows off Swing's Dialog-like object. Here,
when you drag the window around, you'll quickly notice it will not go outside
the demo's area. Also, you can create other frames by selecting the Make
button. If you change the Layer input you'll also notice the support for
z-ordering, or layering of objects.
Before leaving this tab, select another Look & Feel from the Options
menu. Notice how this changes the appearance of the different components.
This is Swing's Pluggable Look & Feel capabilities. Basically, at
run-time, you can permit users to change the appearance of the interface
from the default Metal-style interface to a Windows-95 interface, to
a Motif interface, or any custom interface. Or, you can just enable a
different Look & Feel all the time.
The ListBox tab shows off some new capabilities of lists. The most obvious
addition here is the ability to have images in the list. Selecting an item
also demonstrates that you can change what is shown when an item becomes
selected.
Find out how much a cola, cake, fruit pop, watermelon, and a radish cost,
combined.
Under the Menus & ToolBars tab you'll find the new ToolBar component,
and notice that menus can now have images along with text for menu items,
even on the menu bar. While looking at the menus, find the names of three
cats. While toolbars are draggable by default, this one isn't.
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The last three tabs we'll look at are TreeView, ProgressBar, and HTML Text.
TreeView demonstrates an hierarchical viewer that is now a standard component.
For the Progress Bar, if you select the Start Loading Text button, you'll
notice its behavior, as it loads in a file from disk. With the HTML Text
object, it supports HTML 3.2 display like images, text, and hot links.
At your leisure, stop by the other tabs. You'll get to create the components
in the remaining magercises. So, just get a feel for what's out there now.
When you're done, select File then Exit to close the demonstration.
Where help exists, the task numbers above are linked to the
step-by-step
help page.
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MageLang Institute.
All Rights Reserved.
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