Look and Feel - in Widget Toolkits

In Widget Toolkits

Contrary to operating system user interfaces, for which look and feel is a part of the product identification, Widget toolkits often allow users to specialize their application look and feel, by deriving the default look and feel of the toolkit, or by completely defining their own. This specialization can go from skinning (that only deals with the look, or visual appearance of the widgets) to completely specializing the way the user interacts with the software (that is, the feel).

The definition of the look and feel to associate with the application is often done at initialization, but some Widget toolkits, such as the Swing widget toolkit that is part of the Java API, allow users to change the look and feel at runtime (see Pluggable look and feel).

Some examples of Widget toolkits that support setting a specialized look and feel are:

• XUL (XML User Interface Language): The look and feel of the user interface can be specialized in a CSS file associated with the XUL definition files. Properties that can be specialized from the default are, for example, background or foreground colors of widgets, fonts, size of widgets, and so on.
• Swing supports specializing the look and feel of widgets by deriving from the default, another existing one, creating one from scratch, or beginning with J2SE 5.0, in an XML property file called synth (skinnable look and feel).