Swing components gallery

The following table shows some commonly used Swing components and lists what are probably the most useful and commonly used methods and listeners associated with those components. Remember that we don't list certain methods that are common to all components: for example, you can call setVisible() or setEnabled() on pretty much any component where it'd make sense to do so.

See below for more information on adding listeners to Swing components using the help of an IDE such as Eclipse.

Component	Common constructor parameters	Important methods	Useful Listeners
JButton	Text Icon Text/icon Action		`ActionListener`
JCheckBox	Text Text/selected	`setSelected()` `isSelected()`	`ActionListener ChangeListener`
JRadioButton	Text Text/selected	`setSelected()` `isSelected()` `ButtonGroup.add(...)`	`ActionListener ChangeListener`
JList	Array of items ListModel	`getSelectedValue()` `getSelectedItem()`	`ListSelectionListener`
JTextField	No columns Initial text	`getText()` `setText()` `getDocument()`	`DocumentListener` (Added to Document object returned by `getDocument()`.)
JTextArea	No rows/columns Rows/cols/text	`getText()` `setText()` `getDocument()`
JTabbedPane	Tab placement	`addTab()` `insertTab()` `getSelectedComponent()` `setSelectedComponent()`	`ChangeListener`
JScrollPane	Component Component, scrollbar options	`setViewportView()`
JSplitPane	Orientation, 2 components For orientation, use `JScrollPane.HORIZONTAL_SPLIT` or `JScrollPane.VERTICAL_SPLIT`.	`setDividerLocation()`
JComponent			`MouseListener`

Look and feel

You'll see from the above images that Swing components by default have quite a distinct "look and feel" to them. This will make your application appear similar on different platforms, but has the disadvantage that your apps will look unlike other programs running on the system, and may be offputting to users. However, you can give Swing programs a Windows look and feel (or Mac OS L&F etc) with a simple line of code discussed at the latter link.

Using listeners

In general, every component allows you to attach a number of listeners. A listener is generally a special "mini class" (strictly, it's an implementation of an interface) whose methods will get called when intersting things happen: mouse clicks, button presses etc. When we list that a component uses a particular listener in the table above, then it means you need to add some code such as the following:

JList l = new JList();
l.addListSelectionListener(new ListSelectionListener() {
  ...
});

In the part where we've put ..., you'll need to add definitions of or more methods. Which methods you need to define depends on the particular listener. The easiest way to find out which methods you need to add is to get your IDE to tell you. Figure 1 shows a typical case in Eclipse, for example. When we add the addListSelectionListener() line, a little cross appears to the left of the code (1). Clicking on this cross then gives us the option to "Add Unimplemented Methods" (2). Eclipse then gives us some "template" methods to fill in for that listener.

Figure 1: Using the Eclipse IDE to automatically add listener methods.

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