GUI: PLT Graphics Toolkit

1`` | Overview
- | Windowing
- | Drawing
- | Editor
2`` | Reference
- | Windowing Classes
- | Windowing Functions
- | Drawing Classes
- | Drawing Functions
- | Editor Classes
- | Editor Functions
- | WXME Decoding
3`` | Configuration
4`` | Dynamic Loading
| Index

On this page:

get-direction
get-event-type
get-position
set-direction
set-event-type
set-position

Inherited methods:
from event%
get-time-stamp
set-time-stamp

Version: 4.0.2
contents index
← prev up next →

scroll-event% : class?
superclass: event%

A scroll-event% object contains information about a scroll event. An instance of scroll-event% is always provided to on-scroll.

See get-event-type for a list of the scroll event types.

(new scroll-event% | [ | [event-type event-type] |
|  | [direction direction] |
|  | [position position] |
|  | [time-stamp time-stamp]]) |

→ (is-a?/c scroll-event%)

event-type

:

(one-of/c 'top 'bottom 'line-up 'line-down
'page-up 'page-down 'thumb)

|  |  | = |  | 'thumb

direction : (one-of/c 'horizontal 'vertical) = 'vertical
position : (integer-in 0 10000) = 0
time-stamp : (and/c exact? integer?) = 0

See the corresponding get- and set- methods for information about event-type, direction, position, and time-stamp.

(send a-scroll-event get-direction)
→ (one-of/c 'horizontal 'vertical)

Gets the identity of the scrollbar that was modified by the event, either the horizontal scrollbar or the vertical scrollbar, as 'horizontal or 'vertical, respectively. See also set-direction.

(send a-scroll-event get-event-type)
→ (one-of/c 'top 'bottom 'line-up 'line-down 'page-up 'page-down 'thumb)

Returns the type of the event, one of the following:

- 'top – user clicked a scroll-to-top button

- 'bottom – user clicked a scroll-to-bottom button

- 'line-up – user clicked an arrow to scroll up or left one step

- 'line-down – user clicked an arrow to scroll down or right one step

- 'page-up – user clicked an arrow to scroll up or left one page

- 'page-down – user clicked an arrow to scroll down or right one page

- 'thumb – user dragged the scroll position indicator

(send a-scroll-event get-position) → (integer-in 0 10000)

Returns the position of the scrollbar after the action triggering the event. See also set-position.

(send a-scroll-event set-direction direction) → void?
direction : (one-of/c 'horizontal 'vertical)

Sets the identity of the scrollbar that was modified by the event, either the horizontal scrollbar or the vertical scrollbar, as 'horizontal or 'vertical, respectively. See also get-direction.

(send a-scroll-event set-event-type type) → void?

type

:

(one-of/c 'top 'bottom 'line-up 'line-down
'page-up 'page-down 'thumb)

Sets the type of the event. See get-event-type for information about each event type.

(send a-scroll-event set-position position) → void?
position : (integer-in 0 10000)

Records the position of the scrollbar after the action triggering the event. (The scrollbar itself is unaffected). See also get-position.

contents index
← prev up next →