A Frame object represents a window in a Java GUI application.
To create a window you must extend the Frame class. The following
code shows an example:
import java.awt.*; // import java gui classes
import java.awt.event.*;
public class TestFrame extends Frame
{
// Constructor for frame. This method does the following:
// 1) Initializes the frame by calling it's ancestors constructor
// 2) Sets the window to be 640 x 480 pixels wide
// 3) Creates a window listener and adds it to the frame.
public TestFrame()
{
super("This is the Windows Title");
setBounds(0,0,640,480);
addWindowListener( new FrameWindowListener() );
}
// This inner class handles window events.
// It provides code for the window closing event which
// ends the execution of the application.
class FrameWindowListener extends WindowAdapter
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
}
// void main method of the application.
// It creates an instance of the frame and then shows it.
public static void main(String[] args)
{
TestFrame mainWindow = new TestFrame();
mainWindow.show();
}
}
In the code above not the use of an inner class to provide the code
for handling the closing of the window. The default behavior for the closing
of a window is to simply hide the window. By providing a WindowListener
we can force the termination of the application when the window is closed.
