XtManageChildren(3Xt)RISC/os Reference ManuaXtManageChildren(3Xt)



NAME
     XtManageChildren, XtManageChild, XtUnmanageChildren, XtUn-
     manageChild - 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 com-
          positeWidgetClass.

     ⊕    Returns immediately if the common parent is being des-
          troyed; 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 chil-
          dren 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



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XtManageChildren(3Xt)RISC/os Reference ManuaXtManageChildren(3Xt)



               map_when_managed

               True.

     Managing children is independent of the ordering of children
     and independent of creating and deleting children.  The lay-
     out 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 pro-
     cedure is called to notify it that its set of managed chil-
     dren 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 com-
          positeWidgetClass.

     ⊕    Returns immediately if the common parent is being des-
          troyed; 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 tem-
     porary 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



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XtManageChildren(3Xt)RISC/os Reference ManuaXtManageChildren(3Xt)



     Xlib - C Language X Interface






















































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