Scrollbars support the methods and properties shown in Table A.11.
Table A-11. Scrollbar Properties and Methods
Properties |
Description |
---|---|
command |
Callback is typically used to change the view in the associated
widget (that is, calls that widget’s |
Methods | |
set (first, last) |
This is typically invoked by the associated widget to tell it about the widget’s current view. Both first and last are fractions between and 1. Values of 0.2 and 0.6 tell the scrollbar that the widget is currently showing the area between 20% and 60% of the document, respectively. |
get |
Returns the scrollbar settings as a list (first, last). |
All scrollable widget types that can be scrolled (listbox, text, canvas) support the methods in Table A.12 in addition to their own (and the generic ones listed in Table A.1).
Table A-12. Scrollable Widget Properties and Methods
Properties |
Description |
---|---|
xscrollincrement, yscrollincrement |
If specified, scrolling can be done in units of these increments. |
xscrollcommand, yscrollcommand |
Tell widget what to do when it repositions internally. Typically, this option looks like this:
|
Methods | |
yview (`moveto', fraction) |
|
yview(`scroll', number, what) (similarly for xview) |
This instructs the widget to adjust the view in the window up or down
according to number of increments.
|