Viewport (filter)

A Viewport is a filter that provides scrollbars (both horizontal and vertical) to let you scroll over its child-component when the child's preferred size is bigger than the Viewport's size. In much the same way as a Browser is used to view many lines of text, a Viewport can be used to see a large VBox. Also, Viewports have a mechanism for splitting into two or more views of the child.


Step
(Cardinal, 10)

The number of pixels to move while scrolling.

Axis choices (mutually exclusive):

Vertical
(Boolean, TRUE)

If this is true, the the typing meta-left-click in a vertical scrollbar will split the view of the adjacent window. Meta-right-click will merge two views.
Horizontal
(Boolean, FALSE)

If this is true, the the typing meta-left-click in a horizontal scrollbar will split the view of the adjacent window. Meta-right-click will merge two views.


Scrolling choices (mutually exclusive):
HorAndVer
(Boolean, TRUE)

This puts a horizontal and vertical scrollbar on every view, and a ``reset'' button in the southwest corner that moves the northwest corner of the child to the northwest corner of the view.
HorOnly
(Boolean, FALSE)

Places a horizontal scrollbar at the bottom of the Viewport, and none at the side.
VerOnly
(Boolean, FALSE)

Places a vertical scrollbar on the left side of the Viewport, and none at the bottom.
AlaViewport
(Boolean, FALSE)

This specifies that there is a scrollbar in the same axis as the Viewport. Thus, AlaViewport for a vertical viewport is equivalent to VerOnly.
Auto
(Boolean, FALSE)

This specifies that scroll bars appear only when the preferred size of the child exceeds the size of the Viewport (along that axis).
NoScroll
(Boolean, FALSE)

This specifies that there should be no scrollbars.