ash/wm/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_WINDOW_RESIZER_H_
   6 #define ASH_WM_WINDOW_RESIZER_H_
   7
   8 #include "ash/ash_export.h"
   9 #include "ash/wm/drag_details.h"
  10 #include "ash/wm/window_state.h"
  11 #include "base/basictypes.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "ui/gfx/geometry/rect.h"
  14 #include "ui/wm/public/window_move_client.h"
  15
  16 namespace aura {
  17 class Window;
  18 }
  19
  20 namespace ash {
  21
  22 // WindowResizer is used by ToplevelWindowEventFilter to handle dragging, moving
  23 // or resizing a window. All coordinates passed to this are in the parent
  24 // windows coordinates.
  25 class ASH_EXPORT WindowResizer {
  26  public:
  27   // Constants to identify the type of resize.
  28   static const int kBoundsChange_None;
  29   static const int kBoundsChange_Repositions;
  30   static const int kBoundsChange_Resizes;
  31
  32   // Used to indicate which direction the resize occurs in.
  33   static const int kBoundsChangeDirection_None;
  34   static const int kBoundsChangeDirection_Horizontal;
  35   static const int kBoundsChangeDirection_Vertical;
  36
  37   WindowResizer();
  38   WindowResizer(wm::WindowState* window_state);
  39   virtual ~WindowResizer();
  40
  41   // Returns a bitmask of the kBoundsChange_ values.
  42   static int GetBoundsChangeForWindowComponent(int component);
  43
  44   // Returns a bitmask of the kBoundsChange_ values.
  45   static int GetPositionChangeDirectionForWindowComponent(int window_component);
  46
  47   // Invoked to drag/move/resize the window. |location| is in the coordinates
  48   // of the window supplied to the constructor. |event_flags| is the event
  49   // flags from the event.
  50   virtual void Drag(const gfx::Point& location, int event_flags) = 0;
  51
  52   // Invoked to complete the drag.
  53   virtual void CompleteDrag() = 0;
  54
  55   // Reverts the drag.
  56   virtual void RevertDrag() = 0;
  57
  58   // Returns the target window the resizer was created for.
  59   aura::Window* GetTarget() const {
  60     return window_state_ ? window_state_->window() : NULL;
  61   }
  62
  63   // See comment for |DragDetails::initial_location_in_parent|.
  64   const gfx::Point& GetInitialLocation() const {
  65     return window_state_->drag_details()->initial_location_in_parent;
  66   }
  67
  68   // Drag parameters established when drag starts.
  69   const DragDetails& details() const { return *window_state_->drag_details(); }
  70
  71  protected:
  72   gfx::Rect CalculateBoundsForDrag(const gfx::Point& location);
  73
  74   static bool IsBottomEdge(int component);
  75
  76   // WindowState of the drag target.
  77   wm::WindowState* window_state_;
  78
  79  private:
  80   // In case of touch resizing, adjusts deltas so that the border is positioned
  81   // just under the touch point.
  82   void AdjustDeltaForTouchResize(int* delta_x, int* delta_y);
  83
  84   // Returns the new origin of the window. The arguments are the difference
  85   // between the current location and the initial location.
  86   gfx::Point GetOriginForDrag(int delta_x, int delta_y);
  87
  88   // Returns the size of the window for the drag.
  89   gfx::Size GetSizeForDrag(int* delta_x, int* delta_y);
  90
  91   // Returns the width of the window.
  92   int GetWidthForDrag(int min_width, int* delta_x);
  93
  94   // Returns the height of the drag.
  95   int GetHeightForDrag(int min_height, int* delta_y);
  96 };
  97
  98 // Creates a WindowResizer for |window|. This can return a scoped_ptr
  99 // initialized with NULL if |window| should not be resized nor dragged.
 100 ASH_EXPORT scoped_ptr<WindowResizer> CreateWindowResizer(
 101     aura::Window* window,
 102     const gfx::Point& point_in_parent,
 103     int window_component,
 104     aura::client::WindowMoveSource source);
 105
 106 }  // namespace ash
 107
 108 #endif  // ASH_WM_WINDOW_RESIZER_H_