Java Examples in a Nutshell, 3rd Edition

Custom Dialogs

The ScribbleApp program of Example 11-15 displayed two kinds of dialogs: a confirmation dialog created by JOptionPane and a color selection dialog created by JColorChooser. These Swing components support many basic dialog box needs. The JOptionPane class makes it easy to display simple (and not-so-simple) information, confirmation, and selection dialogs, while JColorChooser and JFileChooser provide color and file selection capabilities. Most nontrivial applications, however, need to create custom dialogs that go beyond these standard components. This is easy to do with the JDialog component.

Example 11-17 shows the FontChooser class. It subclasses JDialog and uses the ItemChooser class developed in Example 11-14 to display font families, styles, and sizes to the user. A FontChooser dialog is pictured in Figure 11-14. The inner class FontChooser.Demo is a simple demonstration application you can use to experiment with the FontChooser dialog.

Figure 11-14. The FontChooser dialog

JDialog is a RootPaneContainer, like JFrame, which means you can’t add children to it directly. You must instead add them to the container returned by getContentPane( ). FontChooser creates a modal dialog, which means that the show( ) method blocks and does not return to the caller until the user dismisses the dialog. Finally, FontChooser is implemented as a subclass of JDialog, so ...