ppapi/c/dev/ppb_scrollbar_dev.h

/* Copyright (c) 2010 The Chromium Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
#ifndef PPAPI_C_DEV_PPB_SCROLLBAR_DEV_H_
#define PPAPI_C_DEV_PPB_SCROLLBAR_DEV_H_

#include "ppapi/c/pp_bool.h"
#include "ppapi/c/pp_instance.h"
#include "ppapi/c/pp_macros.h"
#include "ppapi/c/pp_resource.h"
#include "ppapi/c/pp_stdint.h"

struct PP_Rect;

typedef enum {
  PP_SCROLLBY_PIXEL = 0,
  PP_SCROLLBY_LINE = 1,
  PP_SCROLLBY_PAGE = 2,
  PP_SCROLLBY_DOCUMENT = 3
} PP_ScrollBy_Dev;
PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_ScrollBy_Dev, 4);

#define PPB_SCROLLBAR_DEV_INTERFACE "PPB_Scrollbar(Dev);0.3"

// The interface for a scrollbar.  A scrollbar is a widget, so the functions
// in PPB_Widget can also be used with scrollbar objects.
struct PPB_Scrollbar_Dev {
  // Create a new scrollbar.  Returns 0 if the instance is invalid.
  PP_Resource (*Create)(PP_Instance instance,
                        PP_Bool vertical);

  // Returns PP_TRUE if the given resource is a Scrollbar. Returns PP_FALSE if
  // the resource is invalid or some type other than a scrollbar.
  PP_Bool (*IsScrollbar)(PP_Resource resource);

  // Gets the thickness of a scrollbar.
  uint32_t (*GetThickness)();

  // Get/set the value of the scrollbar.
  uint32_t (*GetValue)(PP_Resource scrollbar);

  void (*SetValue)(PP_Resource scrollbar,
                   uint32_t value);

  // Set the document size (i.e. total length of the region that's being
  // scrolled).
  void (*SetDocumentSize)(PP_Resource scrollbar,
                          uint32_t size);

  // Updates the tickmarks.  Only valid for vertical scrollbars.  "tick_marks"
  // contains "count" PP_Rect objects.
  void (*SetTickMarks)(PP_Resource scrollbar,
                       const struct PP_Rect* tick_marks,
                       uint32_t count);

  // Scroll by "multiplier" pixels/lines/pages units.  Positive values are
  // forward and negative are backward.  If "unit" is document then any positive
  // value goes to the end while any negative value goes to the beginning.
  void (*ScrollBy)(PP_Resource scrollbar,
                   PP_ScrollBy_Dev unit,
                   int32_t multiplier);
};

#endif  /* PPAPI_C_DEV_PPB_SCROLLBAR_DEV_H_ */