ash/wm/workspace/two_step_edge_cycler.h

   1 // Copyright 2014 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 ASH_WM_WORKSPACE_TWO_STEP_EDGE_CYCLER_H_
   6 #define ASH_WM_WORKSPACE_TWO_STEP_EDGE_CYCLER_H_
   7
   8 #include "ash/ash_export.h"
   9 #include "base/basictypes.h"
  10 #include "base/time/time.h"
  11 #include "ui/gfx/point.h"
  12
  13 namespace ash {
  14
  15 // TwoStepEdgeCycler is responsible for cycling between two modes when the mouse
  16 // is at the edge of the workspace. The cycler does not loop so it is impossible
  17 // to get back to the first mode once the second mode is reached.
  18 // TwoStepEdgeCycler should be destroyed once the mouse moves off the edge of
  19 // the workspace.
  20 class ASH_EXPORT TwoStepEdgeCycler {
  21  public:
  22   explicit TwoStepEdgeCycler(const gfx::Point& start);
  23   ~TwoStepEdgeCycler();
  24
  25   // Update which mode should be used as a result of a mouse / touch move.
  26   // |location| is the location of the event.
  27   void OnMove(const gfx::Point& location);
  28
  29   bool use_second_mode() const { return second_mode_; }
  30
  31  private:
  32   // Whether the second mode should be used.
  33   bool second_mode_;
  34
  35   // Time OnMove() was last invoked.
  36   base::TimeTicks time_last_move_;
  37
  38   // The number of moves since the cycler was constructed.
  39   int num_moves_;
  40
  41   // Initial x-coordinate.
  42   int start_x_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(TwoStepEdgeCycler);
  45 };
  46
  47 }  // namespace ash
  48
  49 #endif  // ASH_WM_WORKSPACE_TWO_STEP_EDGE_CYCLER_H_