gauge% : class?

superclass: object%

extends:  control<%>

A gauge is a horizontal or vertical bar for displaying the output value of a bounded integer quantity. Each gauge has an adjustable range, and the gauge’s current value is always between 0 and its range, inclusive. Use set-value to set the value of the gauge.

(new gauge%   [label label]       [range range]       [parent parent]      [ [style style]       [font font]       [enabled enabled]       [vert-margin vert-margin]       [horiz-margin horiz-margin]       [min-width min-width]       [min-height min-height]       [stretchable-width stretchable-width]       [stretchable-height stretchable-height]])

→ (is-a?/c gauge%)

label : (or/c label-string? false/c)

range : (integer-in 1 10000)

parent   :   (or/c (is-a?/c frame%) (is-a?/c dialog%)       (is-a?/c panel%) (is-a?/c pane%))

style   :   (listof (one-of/c 'horizontal 'vertical                   'vertical-label 'horizontal-label                   'deleted))       =   '(horizontal)

font : (is-a?/c font%) = (scheme normal-control-font)

enabled : any/c = #t

vert-margin : (integer-in 0 1000) = 2

horiz-margin : (integer-in 0 1000) = 2

min-width : (integer-in 0 10000) = graphical-minimum-width

min-height : (integer-in 0 10000) = graphical-minimum-height

stretchable-width : any/c = (memq 'horizontal style)

stretchable-height : any/c = (memq 'vertical style)

If label is a string, it is used as the gauge label; otherwise the gauge does not display a label.

If & occurs in label, it is specially parsed; under Windows and X, the character following & is underlined in the displayed control to indicate a keyboard mnemonic. (Under Mac OS X, mnemonic underlines are not shown.) The mnemonic is meaningless for a gauge (as far as on-traverse-char in top-level-window<%> is concerned), but it is supported for consistency with other control types. A programmer may assign a meaning to the mnemonic (e.g., by overriding on-traverse-char).

The range argument is an integer specifying the maximum value of the gauge (inclusive). The minimum gauge value is always 0.

The style list must include either 'horizontal, specifying a horizontal gauge, or 'vertical, specifying a vertical gauge. If style includes 'vertical-label, then the gauge is created with a label above the control; if style does not include 'vertical-label (and optionally includes 'horizontal-label), then the label is created to the left of the gauge. If style includes 'deleted, then the gauge is created as hidden, and it does not affect its parent’s geometry; the gauge can be made active later by calling parent’s add-child method.

The font argument determines the font for the control. For information about the enabled argument, see window<%>. For information about the horiz-margin and vert-margin arguments, see subarea<%>. For information about the min-width, min-height, stretchable-width, and stretchable-height arguments, see area<%>.

(send a-gauge get-range) → (integer-in 1 10000)

Returns the range (maximum value) of the gauge.

(send a-gauge get-value) → (integer-in 0 10000)

Returns the gauge’s current value.

(send a-gauge set-range range) → void?

range : (integer-in 1 10000)

Sets the range (maximum value) of the gauge.

(send a-gauge set-value pos) → void?

pos : (integer-in 0 10000)

Sets the gauge’s current value. If the specified value is larger than the gauge’s range, an exn:fail:contract exception is raised.