Controls and layout managers
Components
Check boxes
A frame with a check box
Common constructors of the JCheckBox class
| Constructor | Description |
|---|---|
| JCheckBox(String) | Creates an unselected check box with a label that contains the specified string. |
| JCheckBox(String, boolean) | Creates a check box with a label that contains the specified string. If the boolean value is true, the check box is selected. |
Some methods that work with check boxes
| Method | Description |
|---|---|
| isSelected() | Returns a true value if the check box is selected. |
| setSelected(boolean) | Checks or unchecks the check box depending on the boolean value. |
| addActionListener(ActionListener) | Adds an action listener to the check box. |
Code that creates the check box
private JCheckBox mailingCheckBox;
mailingCheckBox = new JCheckBox("Add to mailing list", true);
mailingCheckBox.addActionListener(this);
add(mailingCheckBox);
Code that checks the status of the check box
boolean addToList = mailingCheckBox.isSelected();
An actionPerformed method for the check box
public void actionPerformed(ActionEvent e)
{
Object source = e.getSource();
if (source == mailingCheckBox)
{
if (mailingCheckBox.isSelected())
addressTextArea.setEnabled(true);
else
addressTextArea.setEnabled(false);
}
}