The skeleton code currently displays a Button
in an
applet. This applet should also count the number of times the Button
is pressed and display this value in the applet's area of the browser window.
Prerequisites
Skeleton Code
Tasks
Add the instance variable count
to the applet and define the
method increaseCount()
so that it simply increments count
each time it's invoked.
Add the method getCount()
so that it returns count
each time it's invoked.
The core event handling classes are in the java.awt.event
package. Import the entire contents of this package.
To handle the command button action event, add the applet itself as an ActionListener
target for the button. That is, the applet should implement this interface.
Define the actionPerformed()
method so that it calls increaseCount()
to update the count instance variable and repaint()
to display the
current count in the applet window. (You do not have to define repaint()
.)
Define the paint()
method so that it uses drawString()
,
from the Graphics
object that's
passed as an argument, to
display the current count. Your paint()
method will be called by repaint()
in actionPerformed()
.
Where help exists, the task numbers above are linked to the
step-by-step help page.
Solution Source
Demonstration
This exercise only runs within browsers that support the Java Runtime Environment 1.1
and appletviewer
.
If you are using an appropriate browser, try this
exercise. The output should look similar to the following:
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