ash/wm/workspace/workspace_window_resizer.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 ASH_WM_WORKSPACE_WINDOW_RESIZER_H_
   6 #define ASH_WM_WORKSPACE_WINDOW_RESIZER_H_
   7
   8 #include <vector>
   9
  10 #include "ash/wm/window_resizer.h"
  11 #include "ash/wm/workspace/magnetism_matcher.h"
  12 #include "base/compiler_specific.h"
  13 #include "base/gtest_prod_util.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "ui/aura/window_tracker.h"
  17
  18 namespace ash {
  19 class DockedWindowLayoutManager;
  20 class PhantomWindowController;
  21 class TwoStepEdgeCycler;
  22 class WindowSize;
  23
  24 namespace wm {
  25 class WindowState;
  26 }
  27
  28 // WindowResizer implementation for workspaces. This enforces that windows are
  29 // not allowed to vertically move or resize outside of the work area. As windows
  30 // are moved outside the work area they are shrunk. We remember the height of
  31 // the window before it was moved so that if the window is again moved up we
  32 // attempt to restore the old height.
  33 class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
  34  public:
  35   // When dragging an attached window this is the min size we'll make sure is
  36   // visible. In the vertical direction we take the max of this and that from
  37   // the delegate.
  38   static const int kMinOnscreenSize;
  39
  40   // Min height we'll force on screen when dragging the caption.
  41   // TODO: this should come from a property on the window.
  42   static const int kMinOnscreenHeight;
  43
  44   // Snap region when dragging close to the edges. That is, as the window gets
  45   // this close to an edge of the screen it snaps to the edge.
  46   static const int kScreenEdgeInset;
  47
  48   // Distance in pixels that the cursor must move past an edge for a window
  49   // to move or resize beyond that edge.
  50   static const int kStickyDistancePixels;
  51
  52   ~WorkspaceWindowResizer() override;
  53
  54   static WorkspaceWindowResizer* Create(
  55       wm::WindowState* window_state,
  56       const std::vector<aura::Window*>& attached_windows);
  57
  58   // WindowResizer:
  59   void Drag(const gfx::Point& location_in_parent, int event_flags) override;
  60   void CompleteDrag() override;
  61   void RevertDrag() override;
  62
  63  private:
  64   WorkspaceWindowResizer(wm::WindowState* window_state,
  65                          const std::vector<aura::Window*>& attached_windows);
  66
  67  private:
  68   friend class WorkspaceWindowResizerTest;
  69
  70   // The edge to which the window should be snapped at the end of the drag.
  71   enum SnapType {
  72     SNAP_LEFT,
  73     SNAP_RIGHT,
  74     SNAP_NONE
  75   };
  76
  77   // Lays out the attached windows. |bounds| is the bounds of the main window.
  78   void LayoutAttachedWindows(gfx::Rect* bounds);
  79
  80   // Calculates the new sizes of the attached windows, given that the main
  81   // window has been resized (along the primary axis) by |delta|.
  82   // |available_size| is the maximum length of the space that the attached
  83   // windows are allowed to occupy (ie: the distance between the right/bottom
  84   // edge of the primary window and the right/bottom of the desktop area).
  85   // Populates |sizes| with the desired sizes of the attached windows, and
  86   // returns the number of pixels that couldn't be allocated to the attached
  87   // windows (due to min/max size constraints).
  88   // Note the return value can be positive or negative, a negative value
  89   // indicating that that many pixels couldn't be removed from the attached
  90   // windows.
  91   int CalculateAttachedSizes(
  92       int delta,
  93       int available_size,
  94       std::vector<int>* sizes) const;
  95
  96   // Divides |amount| evenly between |sizes|. If |amount| is negative it
  97   // indicates how many pixels |sizes| should be shrunk by.
  98   // Returns how many pixels failed to be allocated/removed from |sizes|.
  99   int GrowFairly(int amount, std::vector<WindowSize>& sizes) const;
 100
 101   // Calculate the ratio of pixels that each WindowSize in |sizes| should
 102   // receive when growing or shrinking.
 103   void CalculateGrowthRatios(const std::vector<WindowSize*>& sizes,
 104                              std::vector<float>* out_ratios) const;
 105
 106   // Adds a WindowSize to |sizes| for each attached window.
 107   void CreateBucketsForAttached(std::vector<WindowSize>* sizes) const;
 108
 109   // If possible snaps the window to a neary window. Updates |bounds| if there
 110   // was a close enough window.
 111   void MagneticallySnapToOtherWindows(gfx::Rect* bounds);
 112
 113   // If possible snaps the resize to a neary window. Updates |bounds| if there
 114   // was a close enough window.
 115   void MagneticallySnapResizeToOtherWindows(gfx::Rect* bounds);
 116
 117   // Finds the neareset window to magentically snap to. Updates
 118   // |magnetism_window_| and |magnetism_edge_| appropriately. |edges| is a
 119   // bitmask of the MagnetismEdges to match again. Returns true if a match is
 120   // found.
 121   bool UpdateMagnetismWindow(const gfx::Rect& bounds, uint32 edges);
 122
 123   // Adjusts the bounds of the window: magnetically snapping, ensuring the
 124   // window has enough on screen... |snap_size| is the distance from an edge of
 125   // the work area before the window is snapped. A value of 0 results in no
 126   // snapping.
 127   void AdjustBoundsForMainWindow(int snap_size, gfx::Rect* bounds);
 128
 129   // Stick the window bounds to the work area during a move.
 130   bool StickToWorkAreaOnMove(const gfx::Rect& work_area,
 131                              int sticky_size,
 132                              gfx::Rect* bounds) const;
 133
 134   // Stick the window bounds to the work area during a resize.
 135   void StickToWorkAreaOnResize(const gfx::Rect& work_area,
 136                                int sticky_size,
 137                                gfx::Rect* bounds) const;
 138
 139   // Returns a coordinate along the primary axis. Used to share code for
 140   // left/right multi window resize and top/bottom resize.
 141   int PrimaryAxisSize(const gfx::Size& size) const;
 142   int PrimaryAxisCoordinate(int x, int y) const;
 143
 144   // Updates the bounds of the phantom window for window snapping.
 145   void UpdateSnapPhantomWindow(const gfx::Point& location,
 146                                const gfx::Rect& bounds);
 147
 148   // Restacks the windows z-order position so that one of the windows is at the
 149   // top of the z-order, and the rest directly underneath it.
 150   void RestackWindows();
 151
 152   // Returns the edge to which the window should be snapped to if the user does
 153   // no more dragging. SNAP_NONE is returned if the window should not be
 154   // snapped.
 155   SnapType GetSnapType(const gfx::Point& location) const;
 156
 157   // Returns true if |bounds_in_parent| are valid bounds for snapped state type
 158   // |snapped_type|.
 159   bool AreBoundsValidSnappedBounds(wm::WindowStateType snapped_type,
 160                                    const gfx::Rect& bounds_in_parent) const;
 161
 162   // Docks or undocks the dragged window.
 163   void SetDraggedWindowDocked(bool should_dock);
 164
 165   wm::WindowState* window_state() { return window_state_; }
 166
 167   const std::vector<aura::Window*> attached_windows_;
 168
 169   // Returns the currently used instance for test.
 170   static WorkspaceWindowResizer* GetInstanceForTest();
 171
 172   bool did_lock_cursor_;
 173
 174   // Set to true once Drag() is invoked and the bounds of the window change.
 175   bool did_move_or_resize_;
 176
 177   // True if the window initially had |bounds_changed_by_user_| set in state.
 178   bool initial_bounds_changed_by_user_;
 179
 180   // The initial size of each of the windows in |attached_windows_| along the
 181   // primary axis.
 182   std::vector<int> initial_size_;
 183
 184   // Sum of the minimum sizes of the attached windows.
 185   int total_min_;
 186
 187   // Sum of the sizes in |initial_size_|.
 188   int total_initial_size_;
 189
 190   // Gives a previews of where the the window will end up. Only used if there
 191   // is a grid and the caption is being dragged.
 192   scoped_ptr<PhantomWindowController> snap_phantom_window_controller_;
 193
 194   // Used to determine whether the window should be snapped or docked when
 195   // the user drags a window to the edge of the screen.
 196   scoped_ptr<TwoStepEdgeCycler> edge_cycler_;
 197
 198   // The edge to which the window should be snapped to at the end of the drag.
 199   SnapType snap_type_;
 200
 201   // Number of mouse moves since the last bounds change. Only used for phantom
 202   // placement to track when the mouse is moved while pushed against the edge of
 203   // the screen.
 204   int num_mouse_moves_since_bounds_change_;
 205
 206   // The mouse location passed to Drag().
 207   gfx::Point last_mouse_location_;
 208
 209   // Window the drag has magnetically attached to.
 210   aura::Window* magnetism_window_;
 211
 212   // Used to verify |magnetism_window_| is still valid.
 213   aura::WindowTracker window_tracker_;
 214
 215   // If |magnetism_window_| is non-NULL this indicates how the two windows
 216   // should attach.
 217   MatchedEdge magnetism_edge_;
 218
 219   // Dock container window layout manager.
 220   DockedWindowLayoutManager* dock_layout_;
 221
 222   // Used to determine if this has been deleted during a drag such as when a tab
 223   // gets dragged into another browser window.
 224   base::WeakPtrFactory<WorkspaceWindowResizer> weak_ptr_factory_;
 225
 226   DISALLOW_COPY_AND_ASSIGN(WorkspaceWindowResizer);
 227 };
 228
 229 }  // namespace ash
 230
 231 #endif  // ASH_WM_WORKSPACE_WINDOW_RESIZER_H_