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/geometry/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   // The direction in which a mouse should travel to switch mode.
  23   enum Direction { DIRECTION_LEFT, DIRECTION_RIGHT };
  24
  25   explicit TwoStepEdgeCycler(const gfx::Point& start, Direction direction);
  26   ~TwoStepEdgeCycler();
  27
  28   // Update which mode should be used as a result of a mouse / touch move.
  29   // |location| is the location of the event.
  30   void OnMove(const gfx::Point& location);
  31
  32   bool use_second_mode() const { return second_mode_; }
  33
  34  private:
  35   // Whether the second mode should be used.
  36   bool second_mode_;
  37
  38   // Time OnMove() was last invoked.
  39   base::TimeTicks time_last_move_;
  40
  41   // The number of moves since the cycler was constructed.
  42   int num_moves_;
  43
  44   // Initial x-coordinate.
  45   int start_x_;
  46
  47   // x-coordinate when paused.
  48   int paused_x_;
  49
  50   // Whether the movement was paused.
  51   bool paused_;
  52
  53   // Determines a preferred movement direction that we are watching.
  54   Direction direction_;
  55
  56   DISALLOW_COPY_AND_ASSIGN(TwoStepEdgeCycler);
  57 };
  58
  59 }  // namespace ash
  60
  61 #endif  // ASH_WM_WORKSPACE_TWO_STEP_EDGE_CYCLER_H_