• Tab—part of a dialog that can contain several groups of components, formatted such that only one group is visible at a time. A Tab component must always contain a set of Layout components; each layout contains the components that must displayed at one time. The Figure - ‘All Components Dialog’ shows a decorated Tab which displays a handle on each layout to allow the user to select which layout is visible.

• Layout—an area of a dialog which can contain any number of other dialog components. A Layout can be used to better control the relative position of components in a dialog, by allowing the grids in different parts of the dialog to adopt unaligned rows or columns. A layout can also be used inside a Tab component.

• Check Button—a button which toggles between a TRUE and FALSE state each time the user selects it.

• Drawing Area—a component which allows points, lines, shapes, images and text (including symbols) to be drawn in a variety of colors.

• Input Panel—a box containing a single line of text. The Input Panel may be set to expect text in different formats, for example a real number or an integer. The Input Panel may also be set to be read-only, when it is used by the application to show information to the user.

• Label—a text string used to label the other components.

• List—a box containing a list of text strings, which can be selected by the user. Users can set the List to allow selection of only one item at a time, or more than one.

• Option Menu—a single-line box which allows selection of a single text string from a list of options. The selection is done using a pull-down menu, which appears when a button next to the text box is selected.

• Progress Bar—a component which shows the progress of a time-consuming action.

• Push Button—a button which performs some action when it is selected. It does not contain any remembered state. Push Buttons appear on almost every dialog as OK and Cancel buttons.

• Radio Group—a set of buttons which individually act like check buttons, but which are connected to each other such that only one can be set to TRUE at any time. Selecting one button sets that button and unsets all others in the group.

• Separator—a separator is for cosmetic purposes only, and helps to visually divide components into logical groups.

• Slider—a device which allows the user to set a value in a predefined range by moving a handle with the mouse. Use sliders in situations where an exact value may not be needed. A slider should usually be tied programmatically with a read-only input panel to show the current value.

• Spin-Box—a box containing a single numerical value that can be directly edited. The spin box also has up- and down-arrow buttons for increasing or decreasing the value in steps. A single click increments or decrements by a single step. Holding a button down makes the value change in repeated steps, first small steps and then large steps. The step sizes can be set for each spin box.

• Table—a set of tabulated rows and columns containing text and other components.

• Text Area—a box containing unformatted text containing any number of lines. It may be set to be read-only and used by the application to output information to the user.

• Thumbwheel—a thumbwheel is similar to slider but provides finer control over a wider range of values. Unlike the slider, it does not provide a visual indication of the current value.

• Tree—a tree contains nodes which are structured and displayed in a hierarchical formation.