Java How to Program (early objects), 9/e

14.11 JComboBox; Using an Anonymous Inner Class for Event Handling

A combo box (sometimes called a drop-down list) enables the user to select one item from a list (Fig. 14.22). Combo boxes are implemented with class JComboBox, which extends class JComponent. JComboBoxes generate ItemEventsjustas JCheckBoxes and JRadioButtons do. This example also demonstrates a special form of inner class that’s used frequently in event handling. The application (Figs. 14.21–14.22) uses a JComboBox to provide a list of four image-file names from which the user can select one image to display. When the user selects a name, the application displays the corresponding image as an Icon on a JLabel. Class ComboBoxTest (Fig. 14.22) contains the main method that executes ...