XtManageChildren(3Xt)       X Version 11(Release 3)       XtManageChildren(3Xt)


NAME
      XtManageChildren, XtManageChild, XtUnmanageChildren, XtUnmanageChild -
      manage and unmanage children

SYNTAX
      typedef Widget *WidgetList;

      void XtManageChildren(children, num_children)
            WidgetList children;
            Cardinal num_children;

      void XtManageChild(child)
            Widget child;

      void XtUnmanageChildren(children, num_children)
            WidgetList children;
            Cardinal num_children;

      void XtUnmanageChild(child)
            Widget child;

ARGUMENTS
      child     Specifies the child.

      children  Specifies a list of child widgets.

      num_children
                Specifies the number of children.

DESCRIPTION
      The XtManageChildren function performs the following:

      ⊕    Issues an error if the children do not all have the same parent or
           if the parent is not a subclass of compositeWidgetClass.

      ⊕    Returns immediately if the common parent is being destroyed;
           otherwise, for each unique child on the list, XtManageChildren
           ignores the child if it already is managed or is being destroyed and
           marks it if not.

      ⊕    If the parent is realized and after all children have been marked,
           it makes some of the newly managed children viewable:

           -    Calls the change_managed routine of the widgets' parent.

           -    Calls XtRealizeWidget on each previously unmanaged child that
                is unrealized.

           -    Maps each previously unmanaged child that has map_when_managed
                True.




10/89                                                                    Page 1

XtManageChildren(3Xt)       X Version 11(Release 3)       XtManageChildren(3Xt)


      Managing children is independent of the ordering of children and
      independent of creating and deleting children.  The layout routine of the
      parent should consider children whose managed field is True and should
      ignore all other children.  Note that some composite widgets, especially
      fixed boxes, call XtManageChild from their insert_child procedure.

      If the parent widget is realized, its change_managed procedure is called
      to notify it that its set of managed children has changed.  The parent
      can reposition and resize any of its children.  It moves each child as
      needed by calling XtMoveWidget, which first updates the x and y fields
      and then calls XMoveWindow if the widget is realized.

      The XtManageChild function constructs a WidgetList of length one and
      calls XtManageChildren.

      The XtUnmanageChildren function performs the following:

      ⊕    Issues an error if the children do not all have the same parent or
           if the parent is not a subclass of compositeWidgetClass.

      ⊕    Returns immediately if the common parent is being destroyed;
           otherwise, for each unique child on the list, XtUnmanageChildren
           performs the following:

           -    Ignores the child if it already is unmanaged or is being
                destroyed and marks it if not.

           -    If the child is realized, it makes it nonvisible by unmapping
                it.

      ⊕    Calls the change_managed routine of the widgets' parent after all
           children have been marked if the parent is realized.

      XtUnmanageChildren does not destroy the children widgets.  Removing
      widgets from a parent's managed set is often a temporary banishment, and,
      some time later, you may manage the children again.

      The XtUnmanageChild function constructs a widget list of length one and
      calls XtUnmanageChildren.

SEE ALSO
      XtMapWidget(3Xt), XtRealizeWidget(3Xt)
      X Toolkit Intrinsics - C Language Interface
      Xlib - C Language X Interface










Page 2                                                                    10/89