Subversion Repositories Kolibri OS

/*

 * Copyright 2009 Paul Blokus 

 *

 * 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 .

 */

/** \file

 * Scrollbar widget (interface).

 */

#ifndef _NETSURF_DESKTOP_SCROLLBAR_H_

#define _NETSURF_DESKTOP_SCROLLBAR_H_

#include 

#include 

#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