Tk_GetScrollInfoObj, Tk_GetScrollInfo − parse arguments for scrolling commands
Tk_GetScrollInfoObj(interp, objc, objv, fractionPtr, stepsPtr)
Tk_GetScrollInfo(interp, argc, argv, fractionPtr, stepsPtr)
Interpreter to use for error reporting. Number of Tcl_Obj’s in objv array. 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. Number of strings in argv array. 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. Filled in with fraction from moveto option, if any. 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. The words starting with objv 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