Tk_GetScrollInfo(3) Tk Library Procedures Tk_GetScrollInfo(3) ______________________________________________________________________________
NAME
Tk_GetScrollInfoObj, Tk_GetScrollInfo - parse arguments for scrolling
commands
SYNOPSIS
#include <tk.h>
int
Tk_GetScrollInfoObj(interp, objc, objv, fractionPtr, stepsPtr)
int
Tk_GetScrollInfo(3)interp, argc, argv, fractionPtr, stepsPtr)
ARGUMENTS
Tcl_Interp *interp (in) Interpreter to use for error
reporting.
int objc (in) Number of Tcl_Obj's in objv
array.
Tcl_Obj *const * objv (in) Argument objects. These repre-
sent the entire widget command,
of which the first word is typi-
cally the widget name and the
second word is typically xview or
yview.
int argc (in) Number of strings in argv array.
const char ** argv (in) Argument strings. These repre-
sent the entire widget command,
of which the first word is typi-
cally the widget name and the
second word is typically xview or
yview.
double *fractionPtr (out) Filled in with fraction from
moveto option, if any.
int *stepsPtr (out) Filled in with line or page count
from scroll option, if any. The
value may be negative.
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DESCRIPTION
Tk_GetScrollInfoObj parses the arguments expected by widget scrolling
commands such as xview and yview. It receives the entire list of words
that make up a widget command and parses the words starting with
objv[2]. The words starting with objv[2] must have one of the follow-
ing forms:
moveto fraction
scroll number units
scroll number pages
Any of the moveto, scroll, units, and pages keywords may be abbrevi-
ated. If objv has the moveto form, TK_SCROLL_MOVETO is returned as
result and *fractionPtr is filled in with the fraction argument to the
command, which must be a proper real value. If objv has the scroll
form, TK_SCROLL_UNITS or TK_SCROLL_PAGES is returned and *stepsPtr is
filled in with the number value, which must be a proper integer. If an
error occurs in parsing the arguments, TK_SCROLL_ERROR is returned and
an error message is left in interpreter interp's result.
Tk_GetScrollInfo is identical in function to Tk_GetScrollInfoObj. How-
ever, Tk_GetScrollInfo accepts string arguments, making it more appro-
priate for use with legacy widgets.
KEYWORDS
parse, scrollbar, scrolling command, xview, yview
Tk 8.0 Tk_GetScrollInfo(3)
tk 8.6.11 - Generated Fri Jan 22 13:33:23 CST 2021