gecko-dev/widget/nsIRollupListener.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef __nsIRollupListener_h__
#define __nsIRollupListener_h__

#include "nsTArray.h"
#include "nsPoint.h"
#include "Units.h"

class nsIContent;
class nsIWidget;

class nsIRollupListener {
 public:
  enum class FlushViews : bool { No, Yes };
  enum class AllowAnimations : bool { No, Yes };
  struct RollupOptions {
    // aCount is the number of popups in a chain to close. If this is
    // zero, then all popups are closed.
    uint32_t mCount = 0;
    // If this is true, then views should be flushed after the rollup.
    FlushViews mFlush = FlushViews::No;
    // This is the mouse pointer position where the event that triggered the
    // rollup occurred, which may be nullptr.
    const mozilla::LayoutDeviceIntPoint* mPoint = nullptr;
    // Whether to allow panel animations.
    AllowAnimations mAllowAnimations = AllowAnimations::Yes;
  };

  /**
   * Notifies the object to rollup, optionally returning the node that
   * was just rolled up in aLastRolledUp, if non-null.
   *
   * aLastRolledUp is not addrefed.
   *
   * Returns true if the event that the caller is processing should be consumed.
   */
  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  virtual bool Rollup(const RollupOptions&,
                      nsIContent** aLastRolledUp = nullptr) = 0;

  /**
   * Asks the RollupListener if it should rollup on mouse wheel events
   */
  virtual bool ShouldRollupOnMouseWheelEvent() = 0;

  /**
   * Asks the RollupListener if it should consume mouse wheel events
   */
  virtual bool ShouldConsumeOnMouseWheelEvent() = 0;

  /**
   * Asks the RollupListener if it should rollup on mouse activate, eg. X-Mouse
   */
  virtual bool ShouldRollupOnMouseActivate() = 0;

  /*
   * Retrieve the widgets for open menus and store them in the array
   * aWidgetChain. The number of menus of the same type should be returned,
   * for example, if a context menu is open, return only the number of menus
   * that are part of the context menu chain. This allows closing up only
   * those menus in different situations. The returned value should be exactly
   * the same number of widgets added to aWidgetChain.
   */
  virtual uint32_t GetSubmenuWidgetChain(
      nsTArray<nsIWidget*>* aWidgetChain) = 0;

  virtual nsIWidget* GetRollupWidget() = 0;

  /**
   * If a native menu is currently shown, closes the menu.
   * Returns true if a native menu was open.
   */
  virtual bool RollupNativeMenu() { return false; }
};

#endif /* __nsIRollupListener_h__ */