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Scale


Description

A Scale should be used to select a value from a range. This component should be composed of a slider, moving within an element that indicates the size of the range, called the trough, and a Label that indicates the current value. The position of the slider indicates the value relative to the range. A Scale can also have buttons with arrow graphics for moving the slider.

Illustration

Other Operations

The following text describes the operations of this component:

BSelect Press
In an arrow button, this action must move the slider one increment in the direction of the side of the slider on which the button was pressed, and autorepeat until the button is released.

In the trough, if the Scale has tick marks, BSelect Press must move the slider one major tick mark in the direction of the side of the slider on which the trough was pressed, and autorepeat until the button is released. It can stop when the slider reaches the position of the pointer. If the Scale does not have tick marks, BSelect Press in the trough must move the slider one large increment in the direction of the side of the slider on which the trough was pressed, and autorepeat until the button is released. It can stop when the slider reaches the position of the pointer.

BSelect Motion
If the button is pressed in the slider, must cause the slider to track the position of the pointer. In a vertical Scale, the slider must track the vertical position of the pointer. In a horizontal Scale, the slider must track the horizontal position of the pointer.
BSelect Press
In the slider trough or an arrow button, this action should move the slider to the end of the Scale on which the button was pressed.
BTransfer Press
In the trough, this action should directly position the slider to the position of the button press.
BTransfer Motion
If the button is pressed in the slider or the trough, must directly position the slider to the point of the button press and then cause the slider to track the position of the pointer. In a vertical Scale, the slider must track the vertical position of the pointer. In a horizontal Scale, the slider must track the horizontal position of the pointer.
If a mouse-based sliding action is in progress, must cancel the sliding action and return the slider to its position prior to the start of the sliding operation.
For vertical Scales, this action must move the slider one increment down.
For vertical Scales, this action must move the slider one increment up.
For horizontal Scales, this action must move the slider one increment left.
For horizontal Scales, this action must move the slider one increment right.

For vertical Scales, this action must move the slider one large increment down.

For vertical Scales, this action must move the slider one large increment up.

For horizontal Scales, this action must move the slider one large increment left.
For horizontal Scales, this action must move the slider one large increment right.
or
Must move the slider to the minimum value.
or
Must move the slider to the maximum value.
Must provide any available help for the Scale.