src/ui/core.h

   1 /* The user interface core */
   2 /* $Id$ */
   3
   4 /*
   5  * hed - Hexadecimal editor
   6  * Copyright (C) 2004  Petr Baudis <pasky@ucw.cz>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #ifndef HED__UI_CORE_H
  23 #define HED__UI_CORE_H
  24
  25 #include "util/lists.h"
  26
  27
  28 /* Initialize the UI core. */
  29 void ui_init(void);
  30
  31 /* Kill the UI core. */
  32 void ui_done(void);
  33
  34 /* Possible prefix */
  35 extern int xprefix; /* Letter prefix (e.g. 'g'). */
  36
  37 /* Final cursor position */
  38 extern int cursor_x, cursor_y;
  39
  40
  41 /* Components */
  42
  43 enum handler_result {
  44         EVH_PASS,
  45         EVH_HOLD,
  46         EVH_SILENTHOLD, // EVH_HOLD, but don't redraw
  47         EVH_XPREFIX,
  48         EVH_CUSTOM_XPREFIX, // @xprefix is not cleared after the handler is done
  49 };
  50
  51 /* Gets called to handle an event. */
  52 struct ui_component;
  53 struct ui_event;
  54 typedef enum handler_result (*ui_comp_handler)(struct ui_component *, const struct ui_event *);
  55
  56 struct ui_component {
  57         struct list_head list;
  58
  59         ui_comp_handler handler;
  60         void *data;
  61 };
  62
  63 /* Register UI component. */
  64 struct ui_component *ui_register(ui_comp_handler handler, void *data);
  65
  66 /* Unregister and free UI component. */
  67 void ui_unregister(struct ui_component *component);
  68
  69
  70 /* Events */
  71
  72 struct ui_event {
  73         enum ui_event_type {
  74                 EV_REDRAW,
  75                 EV_KEYBOARD,
  76                 EV_DONE,
  77         } type;
  78         union {
  79                 struct {
  80                         int ch;
  81                 } keyboard;
  82         } v;
  83 };
  84
  85 /* Poll for an event. Returns negative if nothing happenned.
  86  * (That may occur e.g. when standard input reaches EOF.) */
  87 int ui_pollevent(struct ui_event *event);
  88
  89 /* Propagate an event. (Just sending it to all components now. TODO:
  90  * Hierarchy.) */
  91 void ui_propevent(const struct ui_event *event);
  92
  93 /* Trigger a redraw event. */
  94 static void ui_redraw(void);
  95
  96
  97
  98 /**** Inline functions and such. */
  99
 100 static inline void
 101 ui_redraw(void)
 102 {
 103         static const struct ui_event rev = {
 104                 .type = EV_REDRAW,
 105         };
 106         ui_propevent(&rev);
 107 }
 108
 109 #endif