Reference

gk_viewport(3gk)

Attach scrollbars to a widget

NAME

gk_viewport - Attach scrollbars to a widget

SYNOPSIS

gk_viewport pathname child ?options?

STANDARD OPTIONS

background	height	takeFocus
borderWidth	highlightBackground	relief
colormap	highlightThickness	visual
cursor	highlightColor	width

See the ``options'' manual entry for details on the standard options.

WIDGET-SPECIFIC OPTIONS

Name:	scroll
Class:	Scroll
Command-Line Switch:	-scroll

Specifies which scrollbars are to be attached. This option accepts a list containing one or more of left, right, top or bottom. Only a single vertical or a single horizontal scrollbar should be specified.

Name:	multiUser
Class:	MultiUser
Command-Line Switch:	-multiuser

Specifies whether or not the scrollbars are multi-user scrollbars. If true then the are multi-user scrollbars; if false then they are not. Any Tk boolean value is valid and the default value is true.

DESCRIPTION

This application attaches a vertical and a horizontal scrollbar to a child widget. Where the scrollbars are placed and which ones are displayed depends on the value of the scroll option. The scrollbars used by this widget are the GroupKit scrollbars, ``gk_scrollbar''. Whether or not they are displayed as multi-user scrollbars depends on the value of the multiuser option.

The commands that control the horizontal scrolling of the widget are defined as follows:

1.

if the child doesn't have a xscrollcommand then the horizontal scrolling is ignored.

2.

if the xscrollcommand for the child widget is NOT defined then default definitions are used for xscrollcommand for the child widget and for the command.

3.

if the xscrollcommand for the child widget is definded then the default definitions are NOT used.

A similar approach is used for the vertical scrolling.

WIDGET COMMAND

The gk_viewport command creates a new Tcl command whose name is pathName. This command may be used to invoke various operations on the widget. It has the following general form:

pathName option ?arg arg ...?

Option and the args determine the exact behavior of the command. The following commands are possible for gk_viewport widgets:

pathName configure ?option? ?value option value ...?

Query or modify the configuration options of the widget. If no option is specified, returns a list describing all of the available options for pathName (see Tk_ConfigureInfo for information on the format of this list). If option is specified with no value, then the command returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given widget option(s) to have the given value(s); in this case the command returns an empty string. Option may have any of the values accepted by the gk_viewport command.

pathName cget option

Returns the current value of the configuration option given by option. Option may have any of the values accepted by the text command.

pathName repack

Cause the viewport to be repacked.

pathName xcommand

Return the xscrollbar command for the horizontal scrollbar.

pathName xscrollbar

Return the path name of the horizontal scrollbar.

pathName ycommand

Return the yscrollbar command for the vertical scrollbar.

pathName yscrollbar

Return the path name of the vertical scrollbar.

DEFAULT BINDINGS

The only default bindings are those defined for the GroupKit
scrollbar, See ``gk_scrollbar'' for further details..

NOTE

This widget is built using the GroupKit class builder; see the GroupKit User Manual for more information. Much of the code is based on code from the Wigwam package by Jim Wight.

SEE ALSO

gk_scrollbar(n)

AUTHOR

Shannon Jaeger ([email protected]) Ideas borrowed from Jim Wight, author of Wigwam