Source code

Revision control

Copy as Markdown

Other Tools

/* -*- 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_layers_DragTracker_h
#define mozilla_layers_DragTracker_h
#include "mozilla/EventForwards.h"
#include "mozilla/Maybe.h"
namespace mozilla {
class MouseInput;
namespace layers {
// DragTracker simply tracks a sequence of mouse inputs and allows us to tell
// if we are in a drag or not (i.e. the left mouse button went down and hasn't
// gone up yet).
class DragTracker {
public:
DragTracker();
static bool StartsDrag(const MouseInput& aInput);
static bool EndsDrag(const MouseInput& aInput);
void Update(const MouseInput& aInput);
bool InDrag() const;
bool IsOnScrollbar(bool aOnScrollbar);
private:
Maybe<bool> mOnScrollbar;
bool mInDrag;
};
} // namespace layers
} // namespace mozilla
#endif /* mozilla_layers_DragTracker_h */