xref: /freebsd/contrib/ncurses/menu/m_item_vis.c (revision a521f2116473fbd8c09db395518f060a27d02334)
1 /****************************************************************************
2  * Copyright 2020 Thomas E. Dickey                                          *
3  * Copyright 1998-2004,2010 Free Software Foundation, Inc.                  *
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29 
30 /****************************************************************************
31  *   Author:  Juergen Pfeifer, 1995,1997                                    *
32  ****************************************************************************/
33 
34 /***************************************************************************
35 * Module m_item_vis                                                        *
36 * Tell if menu item is visible                                             *
37 ***************************************************************************/
38 
39 #include "menu.priv.h"
40 
41 MODULE_ID("$Id: m_item_vis.c,v 1.17 2020/02/02 23:34:34 tom Exp $")
42 
43 /*---------------------------------------------------------------------------
44 |   Facility      :  libnmenu
45 |   Function      :  bool item_visible(const ITEM *item)
46 |
47 |   Description   :  A item is visible if it currently appears in the
48 |                    subwindow of a posted menu.
49 |
50 |   Return Values :  TRUE  if visible
51 |                    FALSE if invisible
52 +--------------------------------------------------------------------------*/
53 NCURSES_EXPORT(bool)
54 item_visible(const ITEM * item)
55 {
56   MENU *menu;
57 
58   T((T_CALLED("item_visible(%p)"), (const void *)item));
59   if (item &&
60       (menu = item->imenu) &&
61       (menu->status & _POSTED) &&
62       ((menu->toprow + menu->arows) > (item->y)) &&
63       (item->y >= menu->toprow))
64     returnBool(TRUE);
65   else
66     returnBool(FALSE);
67 }
68 
69 /* m_item_vis.c ends here */
70