mouse_cursor_event_filter.h revision 1320f92c476a1ad9d19dba2a48c72b75566198e9 
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 ASH_DISPLAY_MOUSE_CURSOR_EVENT_FILTER_H
6#define ASH_DISPLAY_MOUSE_CURSOR_EVENT_FILTER_H
7
8#include "ash/ash_export.h"
9#include "ash/display/display_controller.h"
10#include "base/compiler_specific.h"
11#include "base/gtest_prod_util.h"
12#include "base/memory/scoped_ptr.h"
13#include "ui/events/event_handler.h"
14#include "ui/gfx/rect.h"
15
16namespace aura {
17class RootWindow;
18class Window;
19}
20
21namespace ash {
22class SharedDisplayEdgeIndicator;
23
24// An event filter that controls mouse location in extended desktop
25// environment.
26class ASH_EXPORT MouseCursorEventFilter : public ui::EventHandler,
27                                          public DisplayController::Observer {
28 public:
29  enum MouseWarpMode {
30    WARP_ALWAYS,   // Always warp the mouse when possible.
31    WARP_DRAG,     // Used when dragging a window. Top and bottom
32                   // corner of the shared edge is reserved for window
33                   // snapping.
34    WARP_NONE,     // No mouse warping. Used when resizing the window.
35  };
36
37  MouseCursorEventFilter();
38  virtual ~MouseCursorEventFilter();
39
40  void set_mouse_warp_mode(MouseWarpMode mouse_warp_mode) {
41    mouse_warp_mode_ = mouse_warp_mode;
42  }
43
44  // Shows/Hide the indicator for window dragging. The |from|
45  // is the window where the dragging started.
46  void ShowSharedEdgeIndicator(aura::Window* from);
47  void HideSharedEdgeIndicator();
48
49  // DisplayController::Observer:
50  virtual void OnDisplaysInitialized() OVERRIDE;
51  virtual void OnDisplayConfigurationChanged() OVERRIDE;
52
53  // ui::EventHandler:
54  virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
55
56 private:
57  friend class DragWindowResizerTest;
58  friend class MouseCursorEventFilterTest;
59  FRIEND_TEST_ALL_PREFIXES(MouseCursorEventFilterTest, DoNotWarpTwice);
60  FRIEND_TEST_ALL_PREFIXES(MouseCursorEventFilterTest, SetMouseWarpModeFlag);
61  FRIEND_TEST_ALL_PREFIXES(MouseCursorEventFilterTest,
62                           IndicatorBoundsTestOnRight);
63  FRIEND_TEST_ALL_PREFIXES(MouseCursorEventFilterTest,
64                           IndicatorBoundsTestOnLeft);
65  FRIEND_TEST_ALL_PREFIXES(MouseCursorEventFilterTest,
66                           IndicatorBoundsTestOnTopBottom);
67  FRIEND_TEST_ALL_PREFIXES(MouseCursorEventFilterTest,
68                           WarpMouseDifferentScaleDisplaysInNative);
69
70  FRIEND_TEST_ALL_PREFIXES(DragWindowResizerTest, WarpMousePointer);
71
72  // Moves the cursor to the point inside the root that is closest to
73  // the point_in_screen, which is outside of the root window.
74  static void MoveCursorTo(aura::Window* root,
75                           const gfx::Point& point_in_screen);
76
77  // Warps the mouse cursor to an alternate root window when the
78  // mouse location in |event|, hits the edge of the event target's root and
79  // the mouse cursor is considered to be in an alternate display.
80  // Returns true if/ the cursor was moved.
81  bool WarpMouseCursorIfNecessary(ui::MouseEvent* event);
82
83  bool WarpMouseCursorInNativeCoords(const gfx::Point& point_in_native,
84                                     const gfx::Point& point_in_screen);
85
86  // Update the edge/indicator bounds based on the current
87  // display configuration.
88  void UpdateHorizontalEdgeBounds();
89  void UpdateVerticalEdgeBounds();
90
91  // Returns the source and destination window. When the
92  // mouse_warp_mode_ is WARP_DRAG, src_window is the root window
93  // where the drag starts. When the mouse_warp_mode_ is WARP_ALWAYS,
94  // the src_window is always the primary root window, because there
95  // is no difference between moving src to dst and moving dst to src.
96  void GetSrcAndDstRootWindows(aura::Window** src_window,
97                               aura::Window** dst_window);
98
99  void reset_was_mouse_warped_for_test() { was_mouse_warped_ = false; }
100
101  bool WarpMouseCursorIfNecessaryForTest(aura::Window* target_root,
102                                         const gfx::Point& point_in_screen);
103
104  MouseWarpMode mouse_warp_mode_;
105
106  // This flag is used to suppress the accidental mouse warp back to the
107  // original display.
108  bool was_mouse_warped_;
109
110  // The bounds for warp hole windows. |dst_indicator_bounds_| is kept
111  // in the instance for testing.
112  gfx::Rect src_indicator_bounds_;
113  gfx::Rect dst_indicator_bounds_;
114
115  gfx::Rect src_edge_bounds_in_native_;
116  gfx::Rect dst_edge_bounds_in_native_;
117
118  // The root window in which the dragging started.
119  aura::Window* drag_source_root_;
120
121  float scale_when_drag_started_;
122
123  // Shows the area where a window can be dragged in to/out from
124  // another display.
125  scoped_ptr<SharedDisplayEdgeIndicator> shared_display_edge_indicator_;
126
127  DISALLOW_COPY_AND_ASSIGN(MouseCursorEventFilter);
128};
129
130}  // namespace ash
131
132#endif  // ASH_DISPLAY_MOUSE_CURSOR_EVENT_FILTER_H
133