rockbox/apps/gui/list.h

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2005 by Kevin Ferrare
 *
 * 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.
 *
 ****************************************************************************/

#ifndef _GUI_LIST_H_
#define _GUI_LIST_H_

#include "config.h"
#include "icon.h"
#include "screen_access.h"

#define SCROLLBAR_WIDTH global_settings.scrollbar_width

enum list_wrap {
    LIST_WRAP_ON = 0,
    LIST_WRAP_OFF,
    LIST_WRAP_UNLESS_HELD,
};

/*
 * The gui_list is based on callback functions, if you want the list
 * to display something you have to provide it a function that
 * tells it what to display.
 * There are three callback function :
 * one to get the text, one to get the icon and one to get the color
 */

/*
 * Icon callback
 *  - selected_item : an integer that tells the number of the item to display
 *  - data : a void pointer to the data you gave to the list when you
 *           initialized it
 *  Returns a pointer to the icon, the value inside it is used to display the
 *          icon after the function returns.
 * Note : we use the ICON type because the real type depends of the plateform
 */
typedef enum themable_icons list_get_icon(int selected_item, void * data);
/*
 * Text callback
 *  - selected_item : an integer that tells the number of the item to display
 *  - data : a void pointer to the data you gave to the list when you
 *           initialized it
 *  - buffer : a buffer to put the resulting text on it
 *             (The content of the buffer may not be used by the list, we use
 *             the return value of the function in all cases to avoid filling
 *             a buffer when it's not necessary)
 *  - buffer_len : length of the buffer
 * Returns a pointer to a string that contains the text to display
 */
typedef const char * list_get_name(int selected_item, void * data,
                                   char * buffer, size_t buffer_len);
/*
 * Voice callback
 *  - selected_item : an integer that tells the number of the item to speak
 *  - data : a void pointer to the data you gave to the list when you
 *           initialized it
 * Returns an integer, 0 means success, ignored really...
 */
typedef int list_speak_item(int selected_item, void * data);
#ifdef HAVE_LCD_COLOR
/*
 * Color callback
 *  - selected_item : an integer that tells the number of the item to display
 *  - data : a void pointer to the data you gave to the list when you
 *           initialized it
 *  Returns an int with the lower 16 bits representing the color to display the
 *          selected item, negative value for default coloring.
 */
typedef int list_get_color(int selected_item, void * data);
#endif

struct gui_synclist
{
    /* defines wether the list should stop when reaching the top/bottom
     * or should continue (by going to bottom/top) */
    bool limit_scroll;
    /* wether the text of the whole items of the list have to be
     * scrolled or only for the selected item */
    bool scroll_all;

    int nb_items;
    int selected_item;
    int start_item[NB_SCREENS]; /* the item that is displayed at the top of the screen */
    /* the number of lines that are selected at the same time */
    int selected_size;
    /* These are used to calculate how much of the screen content we need
       to redraw. */
    int last_displayed_selected_item;
    int last_displayed_start_item[NB_SCREENS];
#ifdef HAVE_LCD_BITMAP
    int offset_position[NB_SCREENS]; /* the list's screen scroll placement in pixels */
#endif
    /* Cache the width of the title string in pixels/characters */
    int title_width;
    long scheduled_talk_tick, last_talked_tick;

    list_get_icon *callback_get_item_icon;
    list_get_name *callback_get_item_name;
    list_speak_item *callback_speak_item;

    /* The data that will be passed to the callback function YOU implement */
    void * data;
    /* The optional title, set to NULL for none */
    char * title;
    /* Optional title icon */
    enum themable_icons title_icon;
    bool show_selection_marker; /* set to true by default */

#ifdef HAVE_LCD_COLOR
    int title_color;
    list_get_color *callback_get_item_color;
#endif
    struct viewport *parent[NB_SCREENS];
};


#ifdef HAVE_LCD_BITMAP
extern void list_init(void);
/* parse global setting to static int */
extern void gui_list_screen_scroll_step(int ofs);

/* parse global setting to static bool */
extern void gui_list_screen_scroll_out_of_view(bool enable);
#endif /* HAVE_LCD_BITMAP */

extern void gui_synclist_init(
    struct gui_synclist * lists,
    list_get_name callback_get_item_name,
    void * data,
    bool scroll_all,
    int selected_size,
    struct viewport parent[NB_SCREENS] /* NOTE: new screens should NOT set this to NULL */
    );
extern void gui_synclist_set_nb_items(struct gui_synclist * lists, int nb_items);
extern void gui_synclist_set_icon_callback(struct gui_synclist * lists, list_get_icon icon_callback);
extern void gui_synclist_set_voice_callback(struct gui_synclist * lists, list_speak_item voice_callback);
#ifdef HAVE_LCD_COLOR
extern void gui_synclist_set_color_callback(struct gui_synclist * lists, list_get_color color_callback);
#endif
extern void gui_synclist_speak_item(struct gui_synclist * lists);
extern int gui_synclist_get_nb_items(struct gui_synclist * lists);

extern int  gui_synclist_get_sel_pos(struct gui_synclist * lists);

extern void gui_synclist_draw(struct gui_synclist * lists);
extern void gui_synclist_scroll_stop(struct gui_synclist *lists);
extern void gui_synclist_select_item(struct gui_synclist * lists,
                                     int item_number);
extern void gui_synclist_add_item(struct gui_synclist * lists);
extern void gui_synclist_del_item(struct gui_synclist * lists);
extern void gui_synclist_limit_scroll(struct gui_synclist * lists, bool scroll);
extern void gui_synclist_flash(struct gui_synclist * lists);
extern void gui_synclist_set_title(struct gui_synclist * lists, char * title,
                                   enum themable_icons icon);
extern void gui_synclist_hide_selection_marker(struct gui_synclist *lists,
                                                bool hide);
extern bool gui_synclist_item_is_onscreen(struct gui_synclist *lists,
                                          enum screen_type screen, int item);
/*
 * Do the action implied by the given button,
 * returns true if the action was handled.
 * NOTE: *action may be changed regardless of return value
 */
extern bool gui_synclist_do_button(struct gui_synclist * lists,
                                       int *action,
                                       enum list_wrap);

#if  defined(HAVE_TOUCHSCREEN)
/* this needs to be fixed if we ever get more than 1 touchscreen on a target */
unsigned gui_synclist_do_touchscreen(struct gui_synclist * gui_list);
#endif

/* If the list has a pending postponed scheduled announcement, that
   may become due before the next get_action tmieout. This function
   adjusts the get_action timeout appropriately. */
extern int list_do_action_timeout(struct gui_synclist *lists, int timeout);
/* This one combines a get_action call (with timeout overridden by
   list_do_action_timeout) with the gui_synclist_do_button call, for
   convenience. */
extern bool list_do_action(int context, int timeout,
                           struct gui_synclist *lists, int *action,
                           enum list_wrap wrap);


/** Simplelist implementation.
    USe this if you dont need to reimplement the list code, 
    and just need to show a list 
 **/

struct simplelist_info {
    char *title; /* title to show on the list */
    int  count; /* number of items in the list, each item is selection_size high */
    int selection_size; /* list selection size, usually 1 */
    bool hide_selection;
    bool scroll_all;
    int  timeout;
    int  selection; /* the item to select when the list is first displayed */
                    /* when the list is exited, this will be set to the
                       index of the last item selected, or -1 if the list
                       was exited with ACTION_STD_CANCEL                  */
    int (*action_callback)(int action, struct gui_synclist *lists); /* can be NULL */
        /* action_callback notes:
            action == the action pressed by the user 
                _after_ gui_synclist_do_button returns.
            lists == the lists sturct so the callack can get selection and count etc. */
    list_get_icon *get_icon; /* can be NULL */
    list_get_name *get_name; /* NULL if you're using simplelist_addline() */
    list_speak_item *get_talk; /* can be NULL to not speak */
    void *callback_data; /* data for callbacks */
};

#define SIMPLELIST_MAX_LINES 32
#define SIMPLELIST_MAX_LINELENGTH 32

/** The next three functions are used if the text is mostly static.
    These should be called in the action callback for the list.
 **/
/* set the amount of lines shown in the list
   Only needed if simplelist_info.get_name == NULL */
void simplelist_set_line_count(int lines);
/* get the current amount of lines shown */
int simplelist_get_line_count(void);
/* add/edit a line in the list.
   if line_number > number of lines shown it adds the line, else it edits the line */
#define SIMPLELIST_ADD_LINE (SIMPLELIST_MAX_LINES+1)
void simplelist_addline(int line_number, const char *fmt, ...);

/* setup the info struct. members not setup in this function need to be assigned manually
   members set in this function:
    info.selection_size = 1;
    info.hide_selection = false;
    info.scroll_all = false;
    info.action_callback = NULL;
    info.get_icon = NULL;
    info.get_name = NULL;
    info.get_voice = NULL;
    info.timeout = HZ/10;
    info.selection = 0;
*/
void simplelist_info_init(struct simplelist_info *info, char* title,
                          int count, void* data);
                          
/* show a list.
   if list->action_callback != NULL it is called with the action ACTION_REDRAW
    before the list is dislplayed for the first time */
bool simplelist_show_list(struct simplelist_info *info);

#endif /* _GUI_LIST_H_ */