gecko-dev/dom/events/TouchEvent.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 mozilla_dom_TouchEvent_h_
#define mozilla_dom_TouchEvent_h_

#include "mozilla/dom/Touch.h"
#include "mozilla/dom/TouchEventBinding.h"
#include "mozilla/dom/UIEvent.h"
#include "mozilla/Attributes.h"
#include "mozilla/EventForwards.h"
#include "mozilla/TouchEvents.h"
#include "nsJSEnvironment.h"
#include "nsStringFwd.h"
#include "nsWrapperCache.h"

namespace mozilla {
namespace dom {

class TouchList final : public nsISupports, public nsWrapperCache {
 public:
  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(TouchList)

  explicit TouchList(nsISupports* aParent) : mParent(aParent) {
    nsJSContext::LikelyShortLivingObjectCreated();
  }
  TouchList(nsISupports* aParent, const WidgetTouchEvent::TouchArray& aTouches)
      : mParent(aParent), mPoints(aTouches) {
    nsJSContext::LikelyShortLivingObjectCreated();
  }

  void Append(Touch* aPoint) { mPoints.AppendElement(aPoint); }

  virtual JSObject* WrapObject(JSContext* aCx,
                               JS::Handle<JSObject*> aGivenProto) override;

  nsISupports* GetParentObject() const { return mParent; }

  static bool PrefEnabled(JSContext* aCx, JSObject* aGlobal);

  uint32_t Length() const { return mPoints.Length(); }
  Touch* Item(uint32_t aIndex) const { return mPoints.SafeElementAt(aIndex); }
  Touch* IndexedGetter(uint32_t aIndex, bool& aFound) const {
    aFound = aIndex < mPoints.Length();
    if (!aFound) {
      return nullptr;
    }
    return mPoints[aIndex];
  }

  void Clear() { mPoints.Clear(); }

 protected:
  ~TouchList() {}

  nsCOMPtr<nsISupports> mParent;
  WidgetTouchEvent::TouchArray mPoints;
};

class TouchEvent : public UIEvent {
 public:
  TouchEvent(EventTarget* aOwner, nsPresContext* aPresContext,
             WidgetTouchEvent* aEvent);

  NS_DECL_ISUPPORTS_INHERITED
  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(TouchEvent, UIEvent)

  virtual JSObject* WrapObjectInternal(
      JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override {
    return TouchEvent_Binding::Wrap(aCx, this, aGivenProto);
  }

  already_AddRefed<TouchList> CopyTouches(
      const Sequence<OwningNonNull<Touch>>& aTouches);

  TouchList* Touches();
  // TargetTouches() populates mTargetTouches from widget event's touch list.
  TouchList* TargetTouches();
  // GetExistingTargetTouches just returns the existing target touches list.
  TouchList* GetExistingTargetTouches() { return mTargetTouches; }
  TouchList* ChangedTouches();

  bool AltKey();
  bool MetaKey();
  bool CtrlKey();
  bool ShiftKey();

  void InitTouchEvent(const nsAString& aType, bool aCanBubble, bool aCancelable,
                      nsGlobalWindowInner* aView, int32_t aDetail,
                      bool aCtrlKey, bool aAltKey, bool aShiftKey,
                      bool aMetaKey, TouchList* aTouches,
                      TouchList* aTargetTouches, TouchList* aChangedTouches);

  static bool PlatformSupportsTouch();
  static bool PrefEnabled(JSContext* aCx, JSObject* aGlobal);
  static bool PrefEnabled(nsIDocShell* aDocShell);
  static bool LegacyAPIEnabled(JSContext* aCx, JSObject* aGlobal);
  static bool LegacyAPIEnabled(nsIDocShell* aDocShell, bool aCallerIsSystem);

  static already_AddRefed<TouchEvent> Constructor(const GlobalObject& aGlobal,
                                                  const nsAString& aType,
                                                  const TouchEventInit& aParam);

 protected:
  ~TouchEvent() {}

  void AssignTouchesToWidgetEvent(TouchList* aList, bool aCheckDuplicates);

  RefPtr<TouchList> mTouches;
  RefPtr<TouchList> mTargetTouches;
  RefPtr<TouchList> mChangedTouches;
};

}  // namespace dom
}  // namespace mozilla

already_AddRefed<mozilla::dom::TouchEvent> NS_NewDOMTouchEvent(
    mozilla::dom::EventTarget* aOwner, nsPresContext* aPresContext,
    mozilla::WidgetTouchEvent* aEvent);

#endif  // mozilla_dom_TouchEvent_h_