tab_scrubber.h revision d0247b1b59f9c528cb6df88b4f2b9afaf80d181e 
1// Copyright (c) 2012 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#ifndef CHROME_BROWSER_UI_VIEWS_ASH_TAB_SCRUBBER_H_
6#define CHROME_BROWSER_UI_VIEWS_ASH_TAB_SCRUBBER_H_
7
8#include "base/timer/timer.h"
9#include "chrome/browser/ui/views/frame/immersive_mode_controller.h"
10#include "chrome/browser/ui/views/tabs/tab_strip_observer.h"
11#include "content/public/browser/notification_observer.h"
12#include "content/public/browser/notification_registrar.h"
13#include "ui/events/event_handler.h"
14
15class Browser;
16class TabStrip;
17
18namespace gfx {
19class Point;
20}
21
22// Class to enable quick tab switching via Ctrl-left-drag.
23// Notes: this is experimental, and disables ctrl-clicks. It should not be
24// enabled other than through flags until we implement 3 finger drag as the
25// mechanism to invoke it. At that point we will add test coverage.
26class TabScrubber : public ui::EventHandler,
27                    public content::NotificationObserver,
28                    public TabStripObserver {
29 public:
30  enum Direction {LEFT, RIGHT};
31
32  // Returns a the single instance of a TabScrubber.
33  static TabScrubber* GetInstance();
34
35  // Returns the virtual position of a swipe starting in the tab at |index|,
36  // base on the |direction|.
37  static gfx::Point GetStartPoint(TabStrip* tab_strip,
38                                  int index,
39                                  TabScrubber::Direction direction);
40
41  void set_activation_delay(int activation_delay) {
42    activation_delay_ = activation_delay;
43    use_default_activation_delay_ = false;
44  }
45  int activation_delay() const { return activation_delay_; }
46  int highlighted_tab() const { return highlighted_tab_; }
47  bool IsActivationPending();
48
49 private:
50  TabScrubber();
51  virtual ~TabScrubber();
52
53  // ui::EventHandler overrides:
54  virtual void OnScrollEvent(ui::ScrollEvent* event) OVERRIDE;
55
56  // content::NotificationObserver overrides:
57  virtual void Observe(int type,
58                       const content::NotificationSource& source,
59                       const content::NotificationDetails& details) OVERRIDE;
60
61  // TabStripObserver overrides.
62  virtual void TabStripAddedTabAt(TabStrip* tab_strip, int index) OVERRIDE;
63  virtual void TabStripMovedTab(TabStrip* tab_strip,
64                                int from_index,
65                                int to_index) OVERRIDE;
66  virtual void TabStripRemovedTabAt(TabStrip* tab_strip, int index) OVERRIDE;
67  virtual void TabStripDeleted(TabStrip* tab_strip) OVERRIDE;
68
69  Browser* GetActiveBrowser();
70  void FinishScrub(bool activate);
71
72  // Are we currently scrubbing?.
73  bool scrubbing_;
74  // The last browser we used for scrubbing, NULL if |scrubbing_| is
75  // false and there is no pending work.
76  Browser* browser_;
77  // The current accumulated x and y positions of a swipe, in
78  // the coordinates of the TabStrip of |browser_|
79  float swipe_x_;
80  float swipe_y_;
81  // The direction the current swipe is headed.
82  Direction swipe_direction_;
83  // The index of the tab that is currently highlighted.
84  int highlighted_tab_;
85  // Timer to control a delayed activation of the |highlighted_tab_|.
86  base::Timer activate_timer_;
87  // Time to wait in ms before newly selected tab becomes active.
88  int activation_delay_;
89  // Set if activation_delay had been explicitly set.
90  bool use_default_activation_delay_;
91  // Forces the tabs to be revealed if we are in immersive fullscreen.
92  scoped_ptr<ImmersiveRevealedLock> immersive_reveal_lock_;
93
94  content::NotificationRegistrar registrar_;
95  base::WeakPtrFactory<TabScrubber> weak_ptr_factory_;
96
97  DISALLOW_COPY_AND_ASSIGN(TabScrubber);
98};
99
100#endif  // CHROME_BROWSER_UI_VIEWS_ASH_TAB_SCRUBBER_H_
101