src/hscroll.h

   1 /* ncmpc (Ncurses MPD Client)
   2  * (c) 2004-2010 The Music Player Daemon Project
   3  * Project homepage: http://musicpd.org
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #ifndef HSCROLL_H
  21 #define HSCROLL_H
  22
  23 #include "config.h"
  24 #include "ncmpc_curses.h"
  25
  26 #include <glib.h>
  27
  28 /**
  29  * This class is used to auto-scroll text which does not fit on the
  30  * screen.  Call hscroll_init() to initialize the object,
  31  * hscroll_clear() to free resources, and hscroll_set() to begin
  32  * scrolling.
  33  */
  34 struct hscroll {
  35         WINDOW *w;
  36         const char *separator;
  37
  38         /**
  39          * The bounding coordinates on the screen.
  40          */
  41         unsigned x, y, width;
  42
  43         /**
  44          * ncurses attributes for drawing the text.
  45          */
  46         attr_t attrs;
  47
  48         /**
  49          * ncurses colors for drawing the text.
  50          */
  51         short pair;
  52
  53         /**
  54          * The scrolled text, in the current locale.
  55          */
  56         char *text;
  57
  58         /**
  59          * The current scrolling offset.  This is a character
  60          * position, not a screen column.
  61          */
  62         gsize offset;
  63
  64         /**
  65          * The id of the timer which updates the scrolled area every
  66          * second.
  67          */
  68         guint source_id;
  69 };
  70
  71 static inline void
  72 hscroll_reset(struct hscroll *hscroll)
  73 {
  74         hscroll->offset = 0;
  75 }
  76
  77 static inline void
  78 hscroll_step(struct hscroll *hscroll)
  79 {
  80         ++hscroll->offset;
  81 }
  82
  83 char *
  84 strscroll(struct hscroll *hscroll, const char *str, const char *separator,
  85           unsigned width);
  86
  87 /**
  88  * Initializes a #hscroll object allocated by the caller.
  89  */
  90 static inline void
  91 hscroll_init(struct hscroll *hscroll, WINDOW *w, const char *separator)
  92 {
  93         hscroll->w = w;
  94         hscroll->separator = separator;
  95 }
  96
  97 /**
  98  * Sets a text to scroll.  This installs a timer which redraws every
  99  * second with the current window attributes.  Call hscroll_clear() to
 100  * disable it.  This function automatically removes the old text.
 101  */
 102 void
 103 hscroll_set(struct hscroll *hscroll, unsigned x, unsigned y, unsigned width,
 104             const char *text);
 105
 106 /**
 107  * Removes the text and the timer.  It may be reused with
 108  * hscroll_set().
 109  */
 110 void
 111 hscroll_clear(struct hscroll *hscroll);
 112
 113 /**
 114  * Explicitly draws the scrolled text.  Calling this function is only
 115  * allowed if there is a text currently.
 116  */
 117 void
 118 hscroll_draw(struct hscroll *hscroll);
 119
 120 #endif