chrome/browser/ui/views/ash/tab_scrubber.h

   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
  15 class Browser;
  16 class Tab;
  17 class TabStrip;
  18
  19 namespace gfx {
  20 class Point;
  21 }
  22
  23 // Class to enable quick tab switching via Ctrl-left-drag.
  24 // Notes: this is experimental, and disables ctrl-clicks. It should not be
  25 // enabled other than through flags until we implement 3 finger drag as the
  26 // mechanism to invoke it. At that point we will add test coverage.
  27 class TabScrubber : public ui::EventHandler,
  28                     public content::NotificationObserver,
  29                     public TabStripObserver {
  30  public:
  31   enum Direction {LEFT, RIGHT};
  32
  33   // Returns a the single instance of a TabScrubber.
  34   static TabScrubber* GetInstance();
  35
  36   // Returns the virtual position of a swipe starting in the tab at |index|,
  37   // base on the |direction|.
  38   static gfx::Point GetStartPoint(TabStrip* tab_strip,
  39                                   int index,
  40                                   TabScrubber::Direction direction);
  41
  42   void set_activation_delay(int activation_delay) {
  43     activation_delay_ = activation_delay;
  44     use_default_activation_delay_ = false;
  45   }
  46   int activation_delay() const { return activation_delay_; }
  47   int highlighted_tab() const { return highlighted_tab_; }
  48   bool IsActivationPending();
  49
  50  private:
  51   TabScrubber();
  52   ~TabScrubber() override;
  53
  54   // ui::EventHandler overrides:
  55   void OnScrollEvent(ui::ScrollEvent* event) override;
  56
  57   // content::NotificationObserver overrides:
  58   void Observe(int type,
  59                const content::NotificationSource& source,
  60                const content::NotificationDetails& details) override;
  61
  62   // TabStripObserver overrides.
  63   void TabStripAddedTabAt(TabStrip* tab_strip, int index) override;
  64   void TabStripMovedTab(TabStrip* tab_strip,
  65                         int from_index,
  66                         int to_index) override;
  67   void TabStripRemovedTabAt(TabStrip* tab_strip, int index) override;
  68   void TabStripDeleted(TabStrip* tab_strip) override;
  69
  70   Browser* GetActiveBrowser();
  71
  72   void BeginScrub(Browser* browser, BrowserView* browser_view, float x_offset);
  73   void FinishScrub(bool activate);
  74
  75   void ScheduleFinishScrubIfNeeded();
  76
  77   // Updates the direction and the starting point of the swipe.
  78   void ScrubDirectionChanged(Direction direction);
  79
  80   // Updates the X co-ordinate of the swipe taking into account RTL layouts if
  81   // any.
  82   void UpdateSwipeX(float x_offset);
  83
  84   void UpdateHighlightedTab(Tab* new_tab, int new_index);
  85
  86   // Are we currently scrubbing?.
  87   bool scrubbing_;
  88   // The last browser we used for scrubbing, NULL if |scrubbing_| is
  89   // false and there is no pending work.
  90   Browser* browser_;
  91   // The TabStrip of the active browser we're scrubbing.
  92   TabStrip* tab_strip_;
  93   // The current accumulated x and y positions of a swipe, in
  94   // the coordinates of the TabStrip of |browser_|
  95   float swipe_x_;
  96   float swipe_y_;
  97   // The direction the current swipe is headed.
  98   Direction swipe_direction_;
  99   // The index of the tab that is currently highlighted.
 100   int highlighted_tab_;
 101   // Timer to control a delayed activation of the |highlighted_tab_|.
 102   base::Timer activate_timer_;
 103   // Time to wait in ms before newly selected tab becomes active.
 104   int activation_delay_;
 105   // Set if activation_delay had been explicitly set.
 106   bool use_default_activation_delay_;
 107   // Forces the tabs to be revealed if we are in immersive fullscreen.
 108   scoped_ptr<ImmersiveRevealedLock> immersive_reveal_lock_;
 109
 110   content::NotificationRegistrar registrar_;
 111   base::WeakPtrFactory<TabScrubber> weak_ptr_factory_;
 112
 113   DISALLOW_COPY_AND_ASSIGN(TabScrubber);
 114 };
 115
 116 #endif  // CHROME_BROWSER_UI_VIEWS_ASH_TAB_SCRUBBER_H_