overview_gesture_handler.cc revision 4e180b6a0b4720a9b8e9e959a882386f690f08ff 
1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "ash/wm/gestures/overview_gesture_handler.h"
6
7#include "ash/shell.h"
8#include "ash/shell_delegate.h"
9#include "ash/wm/overview/window_selector_controller.h"
10#include "ui/events/event.h"
11#include "ui/events/event_constants.h"
12#include "ui/gfx/rect.h"
13#include "ui/gfx/screen.h"
14
15namespace ash {
16namespace internal {
17
18namespace {
19
20// The number of pixels from the top of the screen (a virtual bezel) to allow
21// the overview swipe down gesture to begin within. Note this does not actually
22// prevent handling of the touches so a fullscreen page which consumes these can
23// prevent entering overview with a swipe down.
24const int kTopBezelExtraPixels = 5;
25
26}  // namespace;
27
28OverviewGestureHandler::OverviewGestureHandler()
29    : in_top_bezel_gesture_(false) {
30}
31
32OverviewGestureHandler::~OverviewGestureHandler() {
33}
34
35bool OverviewGestureHandler::ProcessGestureEvent(
36    const ui::GestureEvent& event) {
37  // Detect at the beginning of any gesture whether it begins on the top bezel.
38  if (event.type() == ui::ET_GESTURE_BEGIN &&
39      event.details().touch_points() == 1) {
40    in_top_bezel_gesture_ = !Shell::GetScreen()->GetDisplayNearestPoint(
41        event.location()).bounds().y() + kTopBezelExtraPixels >
42            event.location().y();
43    return false;
44  }
45
46  if (!in_top_bezel_gesture_ ||
47      event.type() != ui::ET_GESTURE_MULTIFINGER_SWIPE ||
48      !event.details().swipe_down() ||
49      event.details().touch_points() != 3) {
50    return false;
51  }
52
53  Shell* shell = Shell::GetInstance();
54  shell->delegate()->RecordUserMetricsAction(UMA_GESTURE_OVERVIEW);
55  shell->window_selector_controller()->ToggleOverview();
56  return true;
57}
58
59}  // namespace internal
60}  // namespace ash
61