blob: 23bb81a9d175fa5ebf7e81235de1f8a0957fb39f [file] [log] [blame]
// Copyright (c) 2012 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.
#include <memory>
#include "base/macros.h"
#include "base/time/time.h"
#include "ui/gfx/geometry/insets.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/views/views_export.h"
namespace gfx {
class Point;
namespace views {
// MouseWatcherListener is notified when the mouse moves outside the host.
class VIEWS_EXPORT MouseWatcherListener {
virtual void MouseMovedOutOfHost() = 0;
virtual ~MouseWatcherListener();
// The MouseWatcherHost determines what region is to be monitored.
class VIEWS_EXPORT MouseWatcherHost {
// The type of mouse event.
enum class EventType { kMove, kExit, kPress };
virtual ~MouseWatcherHost();
// Return false when the mouse has moved outside the monitored region.
virtual bool Contains(const gfx::Point& screen_point, EventType type) = 0;
// MouseWatcher is used to watch mouse movement and notify its listener when the
// mouse moves outside the bounds of a MouseWatcherHost.
class VIEWS_EXPORT MouseWatcher {
// Creates a new MouseWatcher. The |listener| will be notified when the |host|
// determines that the mouse has moved outside its monitored region.
// |host| will be owned by the watcher and deleted upon completion, while the
// listener must remain alive for the lifetime of this object.
MouseWatcher(std::unique_ptr<MouseWatcherHost> host,
MouseWatcherListener* listener);
// Sets the amount to delay before notifying the listener when the mouse exits
// the host by way of going to another window.
void set_notify_on_exit_time(base::TimeDelta time) {
notify_on_exit_time_ = time;
// Starts watching mouse movements. When the mouse moves outside the bounds of
// the host the listener is notified. |Start| may be invoked any number of
// times. If the mouse moves outside the bounds of the host the listener is
// notified and watcher stops watching events. |window| must be a window in
// the hierarchy related to the host. |window| is used to setup initial state,
// and may be deleted before MouseWatcher.
void Start(gfx::NativeWindow window);
// Stops watching mouse events.
void Stop();
class Observer;
// Are we currently observing events?
bool is_observing() const { return observer_.get() != nullptr; }
// Notifies the listener and stops watching events.
void NotifyListener();
// Host we're listening for events over.
std::unique_ptr<MouseWatcherHost> host_;
// Our listener.
MouseWatcherListener* listener_;
// Does the actual work of listening for mouse events.
std::unique_ptr<Observer> observer_;
// See description above setter.
base::TimeDelta notify_on_exit_time_;
} // namespace views