1Tk_GetScrollInfo(3)          Tk Library Procedures         Tk_GetScrollInfo(3)
2
3
4
5______________________________________________________________________________
6

NAME

8       Tk_GetScrollInfoObj,  Tk_GetScrollInfo  - parse arguments for scrolling
9       commands
10

SYNOPSIS

12       #include <tk.h>
13
14       int
15       Tk_GetScrollInfoObj(interp, objc, objv, fractionPtr, stepsPtr)
16
17       int
18       Tk_GetScrollInfo(interp, argc, argv, fractionPtr, stepsPtr)
19

ARGUMENTS

21       Tcl_Interp *interp (in)               Interpreter to use for error  re‐
22                                             porting.
23
24       int objc (in)                         Number  of  Tcl_Obj's in objv ar‐
25                                             ray.
26
27       Tcl_Obj *const * objv (in)            Argument objects.   These  repre‐
28                                             sent  the  entire widget command,
29                                             of which the first word is  typi‐
30                                             cally  the  widget  name  and the
31                                             second word is typically xview or
32                                             yview.
33
34       int argc (in)                         Number of strings in argv array.
35
36       const char ** argv (in)               Argument  strings.   These repre‐
37                                             sent the entire  widget  command,
38                                             of  which the first word is typi‐
39                                             cally the  widget  name  and  the
40                                             second word is typically xview or
41                                             yview.
42
43       double *fractionPtr (out)             Filled  in  with  fraction   from
44                                             moveto option, if any.
45
46       int *stepsPtr (out)                   Filled in with line or page count
47                                             from scroll option, if any.   The
48                                             value may be negative.
49______________________________________________________________________________
50

DESCRIPTION

52       Tk_GetScrollInfoObj  parses  the arguments expected by widget scrolling
53       commands such as xview and yview.  It receives the entire list of words
54       that  make  up  a  widget  command  and  parses the words starting with
55       objv[2].  The words starting with objv[2] must have one of the  follow‐
56       ing forms:
57              moveto fraction
58              scroll number units
59              scroll number pages
60
61       Any  of  the  moveto, scroll, units, and pages keywords may be abbrevi‐
62       ated.  If objv has the moveto form, TK_SCROLL_MOVETO is returned as re‐
63       sult  and  *fractionPtr  is filled in with the fraction argument to the
64       command, which must be a proper real value.  If  objv  has  the  scroll
65       form,  TK_SCROLL_UNITS  or TK_SCROLL_PAGES is returned and *stepsPtr is
66       filled in with the number value, which must be a proper integer.  If an
67       error  occurs in parsing the arguments, TK_SCROLL_ERROR is returned and
68       an error message is left in interpreter interp's result.
69
70       Tk_GetScrollInfo is identical in function to Tk_GetScrollInfoObj.  How‐
71       ever,  Tk_GetScrollInfo accepts string arguments, making it more appro‐
72       priate for use with legacy widgets.
73

KEYWORDS

75       parse, scrollbar, scrolling command, xview, yview
76
77
78
79Tk                                    8.0                  Tk_GetScrollInfo(3)