rockbox/apps/plugins/lib/simple_viewer.c
Teruaki Kawashima 5af120f1cb some improvements for simple viewer.
* displays a scrollbar if there is more text than currently displayed.
* enables to scroll text by scrollwheel.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@27175 a1c6a512-1295-4272-9138-f99709370657
2010-06-29 13:33:19 +00:00

311 lines
7.8 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2010 Teruaki Kawashima
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "plugin.h"
#include "pluginlib_actions.h"
#include "simple_viewer.h"
#include <ctype.h>
struct view_info {
#ifdef HAVE_LCD_BITMAP
struct font* pf;
struct viewport scrollbar_vp; /* viewport for scrollbar */
#endif
struct viewport vp;
const char *title;
const char *text; /* displayed text */
int display_lines; /* number of lines can be displayed */
int line_count; /* number of lines */
int line; /* current fisrt line */
int start; /* possition of first line in text */
};
static const char* get_next_line(const char *text, struct view_info *info)
{
const char *ptr = text;
const char *space = NULL;
int total, n, w;
total = 0;
while(*ptr)
{
#ifdef HAVE_LCD_CHARCELLS
n = rb->utf8seek(ptr, 1);
w = 1;
#else
unsigned short ch;
n = ((long)rb->utf8decode(ptr, &ch) - (long)ptr);
w = rb->font_get_width(info->pf, ch);
#endif
if (isspace(*ptr))
space = ptr+n;
if (*ptr == '\n')
{
ptr += n;
break;
}
if (total + w > info->vp.width)
break;
ptr += n;
total += w;
}
return *ptr && space? space: ptr;
}
static void calc_line_count(struct view_info *info)
{
const char *ptr = info->text;
int i = 0;
#ifdef HAVE_LCD_BITMAP
bool scrollbar = false;
#endif
while (*ptr)
{
ptr = get_next_line(ptr, info);
i++;
#ifdef HAVE_LCD_BITMAP
if (!scrollbar && i > info->display_lines)
{
ptr = info->text;
i = 0;
info->scrollbar_vp = info->vp;
info->scrollbar_vp.width = rb->global_settings->scrollbar_width;
info->vp.width -= info->scrollbar_vp.width;
if (rb->global_settings->scrollbar != SCROLLBAR_RIGHT)
info->vp.x = info->scrollbar_vp.width;
else
info->scrollbar_vp.x = info->vp.width;
scrollbar = true;
}
#endif
}
info->line_count = i;
}
static void calc_first_line(struct view_info *info, int line)
{
const char *ptr = info->text;
int i = 0;
if (line > info->line_count - info->display_lines)
line = info->line_count - info->display_lines;
if (line < 0)
line = 0;
if (info->line <= line)
{
ptr += info->start;
i = info->line;
}
while (*ptr && i < line)
{
ptr = get_next_line(ptr, info);
i++;
}
info->start = ptr - info->text;
info->line = i;
}
static int init_view(struct view_info *info,
const char *title, const char *text)
{
rb->viewport_set_defaults(&info->vp, SCREEN_MAIN);
#ifdef HAVE_LCD_BITMAP
info->pf = rb->font_get(FONT_UI);
info->display_lines = info->vp.height / info->pf->height;
#else
info->display_lines = info->vp.height;
#endif
info->title = title;
info->text = text;
info->line_count = 0;
info->line = 0;
info->start = 0;
#ifdef HAVE_LCD_BITMAP
/* no title for small screens. */
if (info->display_lines < 4)
{
info->title = NULL;
}
else
{
info->display_lines--;
info->vp.y += info->pf->height;
info->vp.height -= info->pf->height;
}
#endif
calc_line_count(info);
return 0;
}
static void draw_text(struct view_info *info)
{
#ifdef HAVE_LCD_BITMAP
#define OUTPUT_SIZE LCD_WIDTH+1
#else
#define OUTPUT_SIZE LCD_WIDTH*3+1
#endif
static char output[OUTPUT_SIZE];
const char *text, *ptr;
int max_show, line;
struct screen* display = rb->screens[SCREEN_MAIN];
/* clear screen */
display->clear_display();
#ifdef HAVE_LCD_BITMAP
/* display title. */
if(info->title)
{
display->set_viewport(NULL);
display->puts(0, 0, info->title);
}
#endif
max_show = MIN(info->line_count - info->line, info->display_lines);
text = info->text + info->start;
display->set_viewport(&info->vp);
for (line = 0; line < max_show; line++)
{
int len;
ptr = get_next_line(text, info);
len = ptr-text;
while(len > 0 && isspace(text[len-1]))
len--;
rb->memcpy(output, text, len);
output[len] = 0;
display->puts(0, line, output);
text = ptr;
}
#ifdef HAVE_LCD_BITMAP
if (info->line_count > info->display_lines)
{
display->set_viewport(&info->scrollbar_vp);
rb->gui_scrollbar_draw(display, (info->scrollbar_vp.width? 0: 1), 0,
info->scrollbar_vp.width - 1, info->scrollbar_vp.height,
info->line_count, info->line, info->line + max_show,
VERTICAL);
}
#endif
display->set_viewport(NULL);
display->update();
}
static void scroll_up(struct view_info *info, int n)
{
if (info->line <= 0)
return;
calc_first_line(info, info->line-n);
draw_text(info);
}
static void scroll_down(struct view_info *info, int n)
{
if (info->line + info->display_lines >= info->line_count)
return;
calc_first_line(info, info->line+n);
draw_text(info);
}
static void scroll_to_top(struct view_info *info)
{
if (info->line <= 0)
return;
calc_first_line(info, 0);
draw_text(info);
}
static void scroll_to_bottom(struct view_info *info)
{
if (info->line + info->display_lines >= info->line_count)
return;
calc_first_line(info, info->line_count - info->display_lines);
draw_text(info);
}
int view_text(const char *title, const char *text)
{
struct view_info info;
const struct button_mapping *view_contexts[] = {
pla_main_ctx,
};
int button;
init_view(&info, title, text);
draw_text(&info);
/* wait for keypress */
while(1)
{
button = pluginlib_getaction(TIMEOUT_BLOCK, view_contexts,
ARRAYLEN(view_contexts));
switch (button)
{
case PLA_UP:
case PLA_UP_REPEAT:
#ifdef HAVE_SCROLLWHEEL
case PLA_SCROLL_BACK:
case PLA_SCROLL_BACK_REPEAT:
#endif
scroll_up(&info, 1);
break;
case PLA_DOWN:
case PLA_DOWN_REPEAT:
#ifdef HAVE_SCROLLWHEEL
case PLA_SCROLL_FWD:
case PLA_SCROLL_FWD_REPEAT:
#endif
scroll_down(&info, 1);
break;
case PLA_LEFT:
scroll_up(&info, info.display_lines);
break;
case PLA_RIGHT:
scroll_down(&info, info.display_lines);
break;
case PLA_LEFT_REPEAT:
scroll_to_top(&info);
break;
case PLA_RIGHT_REPEAT:
scroll_to_bottom(&info);
break;
case PLA_EXIT:
case PLA_CANCEL:
return PLUGIN_OK;
default:
if (rb->default_event_handler(button) == SYS_USB_CONNECTED)
return PLUGIN_USB_CONNECTED;
break;
}
}
return PLUGIN_OK;
}