Help is available for each task, or you can go straight to
the solution
source code.
Task 1
If you are using JavaTM Development
Kit 1.1.x, you need to add the swingall.jar file to your
class path to compile your Swing programs. In the
Installation
magercise, you installed Swing and set the SWINGHOME
environment variable to the installation directory. Now, you need
to add the archives to the CLASSPATH.
Place command all on one line.
For Solaris:
setenv CLASSPATH ${JDKHOME}/lib/classes.zip:
${SWINGHOME}/swingall.jar.
For Windows 95/NT:
set CLASSPATH=%JDKHOME%\lib\classes.zip;
%SWINGHOME%\swingall.jar;.
For JDKTM 2, you do not need to do
anything special.
Task 2
Starting with the
skeleton code, import the swing package.
import javax.swing.*;
Task 3
To have the components appear one on top of each other, modify the
skeleton's constructor so that it sets the layout to GridLayout
with 3 rows and 1 column.
Add the following method call to the constructor.
setLayout(new GridLayout(3,1));
Task 4
Create top and bottom JButtons with action
event listeners that print "top" and "bottom" to
standard output.
Create the top button and event processing via:
JButton top = new JButton("Top");
top.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("top");
}
});
Create the bottom button and event processing via:
JButton bottom = new JButton("Bottom");
bottom.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("bottom");
}
});
Task 5
Create a JLabel with text "Swing Components are like
AWT 1.1". Add it to the first row of the grid.
Add the following code after the button creation code.
add(new JLabel(
"Swing Components are like AWT 1.1"));
Task 6
Add the top and bottom button to the grid.
add(top);
add(bottom);
Task 7
Save everything and compile the program. Then run it to see the results.
Clicking a button displays a message to the screen.
As a precaution, the Save command appends a "1"
to the end of the filename you want to save. This can help
prevent you from accidently overwriting your source code.
javac FirstAppl.java
java FirstAppl
If you are using a 1.1 version of the JDKTM,
make sure your CLASSPATH environment variable has the
swingall.jar file in it.
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MageLang Institute.
All Rights Reserved.
