In software, a radio button is a small, hollow circle adjacent to text in a configuration menu box. Clicking on the radio button places a solid dot in the circle, selecting the option. Clicking a selected radio button de-selects it, removing the dot. As one radio button is selected, others within the category switch off.
The radio button gets its name from the way a physical radio is controlled. Radios typically feature a line of preset station buttons; when one button is pressed, it releases a previously pressed button. Radio buttons present an either-or opportunity for action. This separates them from checkboxes, also used in software. Checkboxes are used when multiple selections are possible within a category.
Checkboxes, radio buttons, toolbars and workspace windows are all elements of the graphical user interface (GUI). This is the part of the software the user can see and interact with verses the hidden coding “behind the curtain.” A clean, easy-to-understand and attractive GUI can sell an adequate program, while a complicated or counter-intuitive GUI can sink an otherwise good program. Typically, the goal of a commercial programmer is to create software that marries an appealing GUI to solid functionality.
In designing software then, it’s important to choose the right graphical elements for the right job. When user configuration calls for choosing just one selection among two or more choices, the radio button is the right GUI element, offering foolproof functionality to the user. If multiple choices are possible, checkboxes are appropriate.
Radio button selections are not processed until the user clicks a push button, commonly “Save,” “OK,” or “Apply.” If this action is omitted or the user inadvertently clicks “Close” or “Cancel” first, previous selections remain in force. Microsoft™, Apple™ and Linux™ operating systems and programs utilize checkboxes or radio buttons in virtually all configuration menus. Radio buttons or checkboxes are also present in third party software that requires user configuration.
Code snippets and Java-based programs like JRadioButton are freely available to programmers for adding radio buttons to software. There are also tutorials and plenty of information for the burgeoning software author.