Provided by: libmotif-dev_2.3.8-3.1build1_amd64 bug

NAME

       XmProcessTraversal  —  A function that determines which component receives keyboard events
       when a widget has the focus "XmProcessTraversal"

SYNOPSIS

       #include <Xm/Xm.h>
       Boolean XmProcessTraversal(
       Widget widget,
       XmTraversalDirection direction);

DESCRIPTION

       XmProcessTraversal determines which component of a hierarchy receives keyboard events when
       the hierarchy that contains the given widget has keyboard focus.

       XmProcessTraversal  changes  focus  only  when  the  keyboard  focus  policy of the widget
       hierarchy is explicit.  If the XmNkeyboardFocusPolicy of the nearest shell ancestor of the
       given  widget is not XmEXPLICIT, XmProcessTraversal returns False without making any focus
       changes.

       widget    Specifies the widget ID of the widget whose hierarchy is to be traversed

       direction Specifies the direction of traversal

   DEFINITIONS
       In order to be eligible to receive keyboard focus when the shell's  XmNkeyboardFocusPolicy
       is XmEXPLICIT, a widget or gadget must meet the following conditions:

          •  The widget and its ancestors are not in the process of being destroyed.

          •  The  widget  and  its  ancestors  are  sensitive.   A  widget  is sensitive when its
             XmNsensitive and XmNancestorSensitive resources are both True.

          •  The XmNtraversalOn resource for the widget and its ancestors is True.

          •  The widget is viewable.  This means that the widget and its ancestors  are  managed,
             realized,  and  (except  for gadgets) mapped.  Furthermore, in general, some part of
             the widget's rectangular area must be unobscured by the widget's  ancestors.  If  an
             application  unmaps a widget that has its XmNmappedWhenManaged resource set to True,
             the result is undefined.

                 In a ScrolledWindow with an XmNscrollingPolicy of XmAUTOMATIC, a widget that  is
                 obscured  because  it is not within the clip window may be able to receive focus
                 if  some  part  of  the  widget  is   within   the   work   area   and   if   an
                 XmNtraverseObscuredCallback  routine  can  make  the  widget  at least partially
                 visible by scrolling the window.

       In general only primitives, gadgets, and Drawing Area are eligible to receive focus.  Most
       managers cannot receive focus even if they meet all these conditions.

       The  direction argument identifies the kind of traversal action to take.  The descriptions
       of these actions below refer to traversable  non-tab-group  widgets  and  traversable  tab
       groups.

          •  A  traversable  non-tab-group  widget  is  a widget that is not a tab group and that
             meets all the conditions for receiving focus described above.

          •  A traversable tab group widget is a tab group widget that meets the same conditions,
             except  that  a  manager  that is a tab group and meets the other conditions is also
             eligible for traversal as long as it contains a descendant that can receive focus.

       A tab group is a widget whose XmNnavigationType is:

          •  XmTAB_GROUP or XmSTICKY_TAB_GROUP,  if  the  hierarchy  (up  to  the  nearest  shell
             ancestor)  that  contains  the  widget  has  no  widget  whose  XmNnavigationType is
             XmEXCLUSIVE_TAB_GROUPXmEXCLUSIVE_TAB_GROUP or XmSTICKY_TAB_GROUP, if the hierarchy  (up  to  the  nearest
             shell  ancestor)  that contains the widget has any widget whose XmNnavigationType is
             XmEXCLUSIVE_TAB_GROUP

   TRAVERSAL ACTIONS
       The hierarchy to be traversed is that containing the widget argument.  This  hierarchy  is
       traversed  only  up  to the nearest shell; XmProcessTraversal does not move focus from one
       shell to another.  If the shell containing widget does not currently have the  focus,  any
       change  that XmProcessTraversal makes to the element with focus within that shell does not
       take effect until the next time the shell receives focus.

       XmProcessTraversal begins the traversal action from  the  widget  in  the  hierarchy  that
       currently  has keyboard focus or that last had focus when the user traversed away from the
       shell hierarchy.

       The value of the direction argument determines which of three kinds of traversal action to
       take:

          •  Traversal  to  a non-tab-group widget.  This kind of traversal is possible only when
             the  widget  that  currently  has   focus   is   not   a   tab   group;   otherwise,
             XmProcessTraversal returns False for these actions.

                 These  actions  do  not  move  focus from one tab group to another.  The actions
                 first determine the containing tab group.  This is the tab group containing  the
                 widget  that  currently has focus.  The actions traverse only to a non-tab-group
                 widget within the containing tab group.

                 A non-tab-group widget is eligible for this kind of traversal if the  widget  is
                 traversable  and  has no tab group ancestors up to the containing tab group.  If
                 the tab group contains no traversable non-tab-group widgets,  XmProcessTraversal
                 returns False.

                 Following  are  the  possible  values of the direction argument.  Note that when
                 actions  wrap,  wrapping  occurs  in  the  traversal  direction.  The  following
                 describes what happens in a left to right environment:

                    •  XmTRAVERSE_RIGHT—If  the  XmNnavigationType of the containing tab group is
                       not XmEXCLUSIVE_TAB_GROUP, focus moves to the  next  traversable  non-tab-
                       group  widget  to  the right of the widget that currently has focus.  In a
                       left to right environment, at the right side of the tab group this  action
                       wraps  to  the  non-tab-group  widget at the left side and next toward the
                       bottom.  At the rightmost widget in the bottom row of the tab  group  this
                       action  wraps  to  the  non-tab-group widget at the leftmost widget in the
                       upper row.

                           In a right to left environment, at the right side of  the  tab  group,
                           this  action  wraps  to  the non-tab-group widget at the left side and
                           next toward the top. At the rightmost widget in the upper row  of  the
                           tab  group  this  action  wraps  to  the  non-tab-group  widget at the
                           leftmost widget in the bottom row.

                           If  the   XmNnavigationType   of   the   containing   tab   group   is
                           XmEXCLUSIVE_TAB_GROUP,  focus  moves  to the next traversable non-tab-
                           group widget in the tab group, proceeding in the order  in  which  the
                           widgets  appear  in  their parents' XmNchildren lists.  After the last
                           widget in the tab group, this action wraps to the first  non-tab-group
                           widget.

                    •  XmTRAVERSE_LEFT—If  the  XmNnavigationType  of the containing tab group is
                       not XmEXCLUSIVE_TAB_GROUP, focus moves to the  next  traversable  non-tab-
                       group  widget  to  the  left of the widget that currently has focus.  In a
                       left to right environment, at the left side of the tab group  this  action
                       wraps  to  the  non-tab-group widget at the right side and next toward the
                       top.  At the leftmost widget in the upper row of the tab group this action
                       wraps  to  the  non-tab-group widget at the rightmost widget in the bottom
                       row.

                           In a right to left environment, at the left side of the tab group this
                           action  wraps  to  the non-tab-group widget at the right side and next
                           toward the bottom. At the leftmost widget in the bottom row of the tab
                           group  this  action wraps to the non-tab-group widget at the rightmost
                           widget in the upper row.

                           If  the   XmNnavigationType   of   the   containing   tab   group   is
                           XmEXCLUSIVE_TAB_GROUP,  focus  moves  to the previous traversable non-
                           tab-group widget in the tab group, proceeding in the reverse order  in
                           which  the  widgets appear in their parents' XmNchildren lists.  After
                           the first widget in the tab group, this action wraps to the last  non-
                           tab-group widget.

                    •  XmTRAVERSE_DOWN—If  the  XmNnavigationType  of the containing tab group is
                       not XmEXCLUSIVE_TAB_GROUP, focus moves to the  next  traversable  non-tab-
                       group  widget  below  the  widget  that currently has focus.  In a left to
                       right environment, at the bottom of the tab group this action wraps to the
                       non-tab-group  widget at the top and next toward the right.  At the bottom
                       widget in the rightmost column of the tab group this action wraps  to  the
                       non-tab-group widget at the top widget in the leftmost column.

                           In  a  right  to left environment, at the bottom of the tab group this
                           action wraps to the non-tab-group widget at the top  and  next  toward
                           the left. At the bottom widget of the leftmost widget of the tab group
                           this action wraps to the non-tab-group widget at the top widget of the
                           rightmost column.

                           If   the   XmNnavigationType   of   the   containing   tab   group  is
                           XmEXCLUSIVE_TAB_GROUP, focus moves to the  next  traversable  non-tab-
                           group  widget  in  the tab group, proceeding in the order in which the
                           widgets appear in their parents' XmNchildren lists.   After  the  last
                           widget  in the tab group, this action wraps to the first non-tab-group
                           widget.

                    •  XmTRAVERSE_UP—If the XmNnavigationType of the containing tab group is  not
                       XmEXCLUSIVE_TAB_GROUP,  focus  moves to the next traversable non-tab-group
                       widget above the widget that currently has focus.   In  a  left  to  right
                       environment, at the top of the tab group this action wraps to the non-tab-
                       group widget at the bottom and next toward the left.  At the top widget of
                       the  leftmost  column  of  the tab group this action wraps to the non-tab-
                       group widget at the bottom widget of the rightmost column.

                           In a right to left environment, at the  top  of  the  tab  group  this
                           action wraps to the non-tab-group widget at the bottom and next toward
                           the right. At the top widget of the right most column of the tab group
                           this  action wraps to the non-tab-group widget at the bottom widget of
                           the leftmost column.

                           If  the   XmNnavigationType   of   the   containing   tab   group   is
                           XmEXCLUSIVE_TAB_GROUP,  focus  moves  to the previous traversable non-
                           tab-group widget in the tab group, proceeding in the reverse order  in
                           which  the  widgets appear in their parents' XmNchildren lists.  After
                           the first widget in the tab group, this action wraps to the last  non-
                           tab-group widget.

                    •  XmTRAVERSE_NEXT—Focus  moves  to the next traversable non-tab-group widget
                       in the tab group, proceeding in the order in which the widgets  appear  in
                       their parents' XmNchildren lists.  After the last widget in the tab group,
                       this action wraps to the first non-tab-group widget.

                    •  XmTRAVERSE_PREV—Focus moves  to  the  previous  traversable  non-tab-group
                       widget  in  the  tab  group,  proceeding in the reverse order in which the
                       widgets appear in their  parents'  XmNchildren  lists.   After  the  first
                       widget  in  the  tab  group,  this  action wraps to the last non-tab-group
                       widget.

                    •  XmTRAVERSE_HOME—If the XmNnavigationType of the containing  tab  group  is
                       not  XmEXCLUSIVE_TAB_GROUP,  focus moves to the first traversable non-tab-
                       group widget at the initial focus of the tab group.

                           If  the   XmNnavigationType   of   the   containing   tab   group   is
                           XmEXCLUSIVE_TAB_GROUP,  focus  moves to the first traversable non-tab-
                           group widget in the tab group, according to the  order  in  which  the
                           widgets appear in their parents' XmNchildren lists.

          •  Traversal  to  a  tab  group.   These  actions  first  determine  the current widget
             hierarchy and the containing tab group.  The current widget hierarchy is the  widget
             hierarchy  whose root is the nearest shell ancestor of the widget that currently has
             focus.  The containing tab group is is the tab  group  containing  the  widget  that
             currently  has  focus.   If the current widget hierarchy contains no traversable tab
             groups, XmProcessTraversal returns False.

                 Following are the possible values of the direction argument. If any tab group in
                 the  current widget hierarchy has an XmNnavigationType of XmEXCLUSIVE_TAB_GROUP,
                 traversal of tab groups in the hierarchy proceeds to widgets  in  the  order  in
                 which  their XmNnavigationType resources were specified as XmEXCLUSIVE_TAB_GROUP
                 or XmSTICKY_TAB_GROUP.:

                    •  XmTRAVERSE_NEXT_TAB_GROUP—Finds the hierarchy that contains widget,  finds
                       the active tab group (if any), and makes the next tab group the active tab
                       group in the hierarchy.

                    •  XmTRAVERSE_PREV_TAB_GROUP—Finds the hierarchy that contains widget,  finds
                       the active tab group (if any), and makes the previous tab group the active
                       tab group in the hierarchy.

          •  Traversal to any widget.  In this case the widget argument is the  widget  to  which
             XmProcessTraversal  tries  to  give  focus.   If  the  widget  is  not  traversable,
             XmProcessTraversal returns False.

                 Following are the possible values of the direction argument:

                    •  XmTRAVERSE_CURRENT—Finds the hierarchy and  the  tab  group  that  contain
                       widget.   If this tab group is not the active tab group, this action makes
                       it the active tab group.  If widget is an item in the  active  tab  group,
                       this  action makes it the active item.  If widget is the active tab group,
                       this action makes the first traversable item in the tab group  the  active
                       item.

   CAUTIONS
       Using XmProcessTraversal to traverse to MenuBars, Pulldown menu panes, or Popup menu panes
       is not supported.

       XmProcessTraversal cannot be called recursively.  In  particular,  an  application  cannot
       call this routine from an XmNfocusCallback or XmNlosingFocusCallback procedure.

RETURN

       Returns    True   if   the   traversal   action   succeeded.    Returns   False   if   the
       XmNkeyboardFocusPolicy of the nearest shell ancestor of widget is not XmEXPLICIT,  if  the
       traversal  action  finds  no  traversable  widget  to receive focus, or if the call to the
       routine has invalid arguments.

RELATED

       XmGetVisibility(3) and XmIsTraversable(3).

                                                                            XmProcessTraversal(3)