/*
* Copyright 2009 Paul Blokus <paul_pl@users.sourceforge.net>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf 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; version 2 of the License.
*
* NetSurf is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/** \file
* Scrollbar widget (interface).
*/
#ifndef _NETSURF_DESKTOP_SCROLLBAR_H_
#define _NETSURF_DESKTOP_SCROLLBAR_H_
#include <stdbool.h>
#include <limits.h>
#include "desktop/browser.h"
#define SCROLLBAR_WIDTH 16
/* Region dependent values for scrollbar_scroll function */
#define SCROLL_TOP INT_MIN
#define SCROLL_PAGE_UP INT_MIN + 1
#define SCROLL_PAGE_DOWN INT_MAX - 1
#define SCROLL_BOTTOM INT_MAX
struct scrollbar;
typedef enum {
SCROLLBAR_MSG_MOVED, /* the scroll value has changed */
SCROLLBAR_MSG_SCROLL_START, /* a scrollbar drag has started, all
* mouse events should be passed to
* the scrollbar regardless of the
* coordinates
*/
SCROLLBAR_MSG_SCROLL_FINISHED, /* cancel the above */
} scrollbar_msg;
struct scrollbar_msg_data {
struct scrollbar *scrollbar;
scrollbar_msg msg;
int scroll_offset;
int x0, y0, x1, y1;
};
/**
* Client callback for the scrollbar.
*
* \param client_data user data passed at scroll creation
* \param scrollbar_data scrollbar message data
*/
typedef void(*scrollbar_client_callback)(void *client_data,
struct scrollbar_msg_data *scrollbar_data);
/**
* Create a scrollbar.
*
* \param horizontal true = horizontal scrollbar, false = vertical
* \param length length of scrollbar widget
* \param full_size length of contained scrollable area
* \param visible_size length of visible part of scrollable area
* \param client_data data for the client callback
* \param client_callback client callback for scrollbar events
* \param s updated to point at the newly created scrollbar
* \return true if scrollbar has been created succesfully or false on
* memory exhaustion
*/
bool scrollbar_create(bool horizontal, int length, int full_size,
int visible_size, void *client_data,
scrollbar_client_callback client_callback,
struct scrollbar **s);
/**
* Destroy a scrollbar.
*
* \param s the scrollbar to be destroyed
*/
void scrollbar_destroy(struct scrollbar *s);
/**
* Redraw a part of the scrollbar.
*
* \param s the scrollbar to be redrawn
* \param x the X coordinate to draw the scrollbar at
* \param y the Y coordinate to draw the scrollbar at
* \param clip the clipping rectangle
* \param scale scale for the redraw
* \param ctx current redraw context
* \return true on succes false otherwise
*/
bool scrollbar_redraw(struct scrollbar *s, int x, int y,
const struct rect *clip, float scale,
const struct redraw_context *ctx);
/**
* Set the scroll value of the scrollbar.
*
* \param s the scrollbar to have the value set
* \param value the new value to be set
* \param bar_pos true if the value is for the scrollbar indication bar
* position, false if it is for the scrolled area offset
*/
void scrollbar_set(struct scrollbar *s, int value, bool bar_pos);
/**
* Scroll the scrollbar by given amount.
*
* \param s the scrollbar to be scrolled
* \param change the change in scroll offset required (in px)
* \return true iff the scrollbar was moved.
*/
bool scrollbar_scroll(struct scrollbar *s, int change);
/**
* Get the current scroll offset to the visible part of the full area.
*
* \param s the scrollbar to get the scroll offset value from
* \return current scroll offset
*/
int scrollbar_get_offset(struct scrollbar *s);
/**
* Set the length of the scrollbar widget, the size of the visible area, and the
* size of the full area.
*
* \param s the scrollbar to set the values for
* \param length -1 or the new scrollbar widget length
* \param visible_size -1 or the new size of the visible area
* \param full_size -1 or the new size of the full contained area
*/
void scrollbar_set_extents(struct scrollbar *s, int length,
int visible_size, int full_size);
/**
* Check orientation of the scrollbar.
*
* \param s the scrollbar to check the orientation of
* \return true for a horizontal scrollbar, else false (vertical)
*/
bool scrollbar_is_horizontal(struct scrollbar *s);
/**
* Handle mouse actions other then drag ends.
*
* \param s the scrollbar which gets the mouse action
* \param mouse mouse state
* \param x X coordinate of the mouse
* \param y Y coordinate of the mouse
* \return message for the status bar or NULL on failure
*/
const char *scrollbar_mouse_action(struct scrollbar *s,
browser_mouse_state mouse, int x, int y);
/**
* Handle end of mouse drags.
*
* \param s the scrollbar for which the drag ends
* \param mouse mouse state
* \param x X coordinate of the mouse
* \param y Y coordinate of the mouse
*/
void scrollbar_mouse_drag_end(struct scrollbar *s,
browser_mouse_state mouse, int x, int y);
/**
* Called when the content is being dragged to the scrollbars have to adjust.
* If the content has both scrollbars, and scrollbar_make_pair has beed called
* before, only the one scroll which will receive further mouse events has to be
* passed.
*
* \param s one of the the scrollbars owned by the dragged content
* \param x X coordinate of mouse during drag start
* \param y Y coordinate of mouse during drag start
*/
void scrollbar_start_content_drag(struct scrollbar *s, int x, int y);
/**
* Connect a horizontal and a vertical scrollbar into a pair so that they
* co-operate during 2D drags.
*
* \param horizontal the scrollbar used for horizontal scrolling
* \param vertical the scrollbar used for vertical scrolling
*/
void scrollbar_make_pair(struct scrollbar *horizontal,
struct scrollbar *vertical);
/**
* Get the scrollbar's client data
*
* \param s the scrollbar to get the client data from
* \return client data
*/
void *scrollbar_get_data(struct scrollbar *s);
#endif