Help is available for each task, or you can go straight to the solution source code.

Task 1

Import the swing package.

import javax.swing.*;

Define two Icon instance variables in class FirstSwing called bee and dog. Then, load the bee.gif and dog.gif image files.

public Icon bee = new ImageIcon("bee.gif");
public Icon dog = new ImageIcon("dog.gif");

Create buttons top and bottom with icons bee and dog.

The following code defines the top button.

JButton top = new JButton("A bee", bee);
top.addActionListener(new ActionListener() {
  public void actionPerformed(ActionEvent e) {
    System.out.println("bee");
  }
});

The following code defines the bottom button.

JButton bottom = new JButton("and a dog", dog);
bottom.addActionListener(new ActionListener() {
  public void actionPerformed(ActionEvent e) {
    System.out.println("dog");
  }
});

Add an accelerator for each button.

Use the setMnemonic() method.

top.setMnemonic (KeyEvent.VK_B);
bottom.setMnemonic (KeyEvent.VK_D);

When working with a JFrame, you add components to an internal area of the JFrame, instead of the actual frame. Get a reference to this Container via the getContentPane() method.

Container content = getContentPane();

To have the buttons appear one on top of each other, modify the skeleton's constructor so that it sets the content's layout to GridLayout with 2 rows and 1 column.

Add the following method call to the constructor.

content.setLayout(new GridLayout(2,1));

Add the buttons to the grid layout.

content.add(top);
content.add(bottom);

Save everything and compile the program. Then run it to see the results. Clicking a button or using the accelerator 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 FirstSwing.java
java FirstSwing

If you are using Swing with Java^TM Developer Kit 1.1.+, make sure your CLASSPATH environment variable has the swingall.jar file in it.

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