DOKK / manpages / debian 10 / tk8.6-doc / Tk_GetScrollInfo.3tk.en
Tk_GetScrollInfo(3tk) Tk Library Procedures Tk_GetScrollInfo(3tk) 







Tk_GetScrollInfoObj, Tk_GetScrollInfo - parse arguments for
    scrolling commands








#include <tk.h>

int
Tk_GetScrollInfoObj(interp, objc, objv, dblPtr, intPtr)

int
Tk_GetScrollInfo(interp, argc, argv, dblPtr, intPtr)









  
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 represent the entire widget command, of which the
      first word is typically 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 represent the entire widget command, of which the
      first word is typically 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.
    
    

    

  










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 following forms:




moveto fraction
scroll number units
scroll number pages




Any of the moveto, scroll, units, and
    pages keywords may be abbreviated. 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. However, Tk_GetScrollInfo accepts string
    arguments, making it more appropriate for use with legacy widgets.








parse, scrollbar, scrolling command, xview, yview







  

    8.0
    Tk