tk4.2 User Commands - focusNext






NAME

     tk_focusNext, tk_focusPrev, tk_focusFollowsMouse  -  Utility
     procedures for managing the input focus.


SYNOPSIS

     tk_focusNext window

     tk_focusPrev window

     tk_focusFollowsMouse





DESCRIPTION

     tk_focusNext  is  a  utility  procedure  used  for  keyboard
     traversal.   It  returns the ``next'' window after window in
     focus order.  The focus order is determined by the  stacking
     order  of windows and the structure of the window hierarchy.
     Among siblings, the focus order is the same as the  stacking
     order,  with the lowest window being first.  If a window has
     children, the window is visited first, followed by its chil-
     dren (recursively), followed by its next sibling.  Top-level
     windows other than window are skipped, so that  tk_focusNext
     never returns a window in a different top-level from window.

     After computing the next window, tk_focusNext  examines  the
     window's  - takefocus  option  to  see  whether it should be
     skipped.  If so, tk_focusNext continues on to the next  win-
     dow  in  the focus order, until it eventually finds a window
     that will accept the focus or returns back to window.

     tk_focusPrev is  similar  to  tk_focusNext  except  that  it
     returns the window just before window in the focus order.

     tk_focusFollowsMouse changes the focus model for the  appli-
     cation  to  an implicit one where the window under the mouse
     gets the focus.  After this procedure  is  called,  whenever
     the  mouse enters a window Tk will automatically give it the
     input focus.  The focus command may  be  used  to  move  the
     focus to a window other than the one under the mouse, but as
     soon as the mouse moves into a new  window  the  focus  will
     jump  to that window.  Note: at present there is no built-in
     support for returning the application to an  explicit  focus
     model;   to  do  this  you'll  have  to  write a script that
     deletes the bindings created by tk_focusFollowsMouse.



KEYWORDS

     focus, keyboard traversal, top-level