XtManageChildren(3Xt)         X11 SDE 5.4R3.00         XtManageChildren(3Xt)


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

SYNTAX
       typedef Widget *WidgetList;

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

       void XtManageChild(child)
             Widget child;

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

       void XtUnmanageChild(child)
             Widget child;

ARGUMENTS
       child     Specifies the child.

       children  Specifies a list of child widgets.

       numchildren
                 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.

       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



Licensed material--property of copyright holder(s)                         1

XtManageChildren(3Xt)         X11 SDE 5.4R3.00         XtManageChildren(3Xt)


       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















Licensed material--property of copyright holder(s)                         2