Help is available for each task, or you can go straight to
the solution source code.
Task 1
Import the Swing border package.
import javax.swing.border.*;
Task 2
Get a reference to the internal contents area of the JFrame.
Container content = getContentPane();
Task 3
Create a 2 row by 3 column grid to layout the buttons in. Leave a 5
pixel horizontal and vertical gap, to better show where the various
buttons begin and end.
Add the following method call to the constructor.
content.setLayout (new GridLayout (2, 3, 5, 5));
Task 4
For the first button, create a JButton and set its border to
a gray LineBorder. Have the button's label be "One,"
and add it to the display.
You can either pass the LineBorder constructor the color gray
or use the createGrayLineBorder() method.
b = new JButton("One");
b.setBorder (LineBorder.createGrayLineBorder());
content.add (b);
Task 5
For the second button, create a JButton and set its border to
be a EtchedBorder. Have the button's label be "Two,"
and add it to the display.
b = new JButton("Two");
b.setBorder(new EtchedBorder());
content.add (b);
Task 6
For the third button, create a JButton and set its border to
be empty, with two pixels of space all around. EmptyBorder is
the empty border. Have the button's label be "Three," and add
it to the display.
b = new JButton("Three");
b.setBorder(new EmptyBorder(2,2,2,2));
content.add (b);
Task 7
For button four, use a TitledBorder to display a title of
"Press Me" in a blue, 10-point italic Serif font, centered
on the top of a black LineBorder. Have the button's label be
"Four," and add it to the display next.
b = new JButton("Four");
b.setBorder(new TitledBorder(
LineBorder.createBlackLineBorder(),
"Press Me",
TitledBorder.CENTER,
TitledBorder.TOP,
new Font ("Serif", Font.ITALIC, 10),
Color.blue));
content.add (b);
Task 8
Before creating the fifth button, create a subclass of JButton
that will show a different border when the button is selected (pressed-in).
Call the class DoubleBorderedButton and have its constructor
accept two Border objects as parameters. Add a MouseListener
and have it toggle between the borders when the mouse button is pressed or
not.
class DoubleBorderedButton extends JButton {
public DoubleBorderedButton (final Border normal,
final Border selected) {
setBorder (normal);
addMouseListener (new MouseAdapter() {
public void mousePressed (MouseEvent e) {
setBorder (selected);
}
public void mouseReleased (MouseEvent e) {
setBorder (normal);
}
});
}
}
Task 9
Now, for the fifth button, create a DoubleBorderedButton. Have
one of the borders be a raised BevelBorder with a blue highlight
color and a yellow shadow. For the other, have the border be a lowered
BevelBorder with the same colors. Have the button's label be
"Five," and add it to the display.
b = new DoubleBorderedButton(
new BevelBorder(BevelBorder.RAISED,
Color.blue, Color.yellow),
new BevelBorder(BevelBorder.LOWERED,
Color.blue, Color.yellow));
b.setText ("Five");
content.add (b);
Task 10
The final button uses a new border, DashedBorder that shows a
dashed border line, instead of the solid one used with LineBorder.
Before you can use it though, you need to complete the definition. The
Border interface has three methods, paintBorder(),
isBorderOpaque(), and getBorderInsets(). The
paintBorder() and isBorderOpaque() methods are already
defined. Define the getBorderInsets() method to return an
Insets object that is THICKNESS wide/high all around.
THICKNESS is a constant defined within the DashedBorder
class.
public Insets getBorderInsets(Component c) {
return new Insets (THICKNESS, THICKNESS,
THICKNESS, THICKNESS);
}
Task 11
Since the code to add the sixth button is already present, you only need
to save everything and compile the program. Then run it to see the results.
Be sure to select the fifth and sixth buttons to show the selected border.
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 Borders.java
java Borders
If you are using Swing with JDK 1.1.+, make sure your CLASSPATH
environment variable has the swingall.jar file in it.
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MageLang Institute.
All Rights Reserved.
