ui/gfx/screen.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 UI_GFX_SCREEN_H_
   6 #define UI_GFX_SCREEN_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "ui/gfx/display.h"
  12 #include "ui/gfx/geometry/point.h"
  13 #include "ui/gfx/gfx_export.h"
  14 #include "ui/gfx/native_widget_types.h"
  15 #include "ui/gfx/screen_type_delegate.h"
  16
  17 namespace gfx {
  18 class DisplayObserver;
  19 class Rect;
  20
  21 // A utility class for getting various info about screen size, displays,
  22 // cursor position, etc.
  23 //
  24 // Note that this class does not represent an individual display connected to a
  25 // computer -- see the Display class for that. A single Screen object exists on
  26 // most operating systems regardless of the number of connected displays. On
  27 // Windows 8, two Screens exist: one for Metro UI and another for the desktop.
  28 class GFX_EXPORT Screen {
  29  public:
  30   // Retrieves the Screen that the specified NativeView belongs to. A value of
  31   // NULL is treated as |SCREEN_TYPE_NATIVE|.
  32   static Screen* GetScreenFor(NativeView view);
  33
  34   // Returns the SCREEN_TYPE_NATIVE Screen. This should be used with caution,
  35   // as it is likely to be incorrect for code that runs on Windows.
  36   static Screen* GetNativeScreen();
  37
  38   // Sets the global screen for a particular screen type. Only the _NATIVE
  39   // ScreenType must be provided.
  40   // NOTE: this does not take ownership of |screen|. Tests must be sure to
  41   // reset any state they install.
  42   static void SetScreenInstance(ScreenType type, Screen* instance);
  43
  44   // Returns the global screen for a particular type. Types other than _NATIVE
  45   // may be NULL.
  46   static Screen* GetScreenByType(ScreenType type);
  47
  48   // Sets the global ScreenTypeDelegate. May be left unset if the platform
  49   // uses only the _NATIVE ScreenType.
  50   // NOTE: this does not take ownership of |delegate|. Tests must be sure to
  51   // reset any state they install.
  52   static void SetScreenTypeDelegate(ScreenTypeDelegate* delegate);
  53
  54   Screen();
  55   virtual ~Screen();
  56
  57   // Returns the current absolute position of the mouse pointer.
  58   virtual gfx::Point GetCursorScreenPoint() = 0;
  59
  60   // Returns the window under the cursor.
  61   virtual gfx::NativeWindow GetWindowUnderCursor() = 0;
  62
  63   // Returns the window at the given screen coordinate |point|.
  64   virtual gfx::NativeWindow GetWindowAtScreenPoint(const gfx::Point& point) = 0;
  65
  66   // Returns the number of displays.
  67   // Mirrored displays are excluded; this method is intended to return the
  68   // number of distinct, usable displays.
  69   virtual int GetNumDisplays() const = 0;
  70
  71   // Returns the list of displays that are currently available.
  72   virtual std::vector<gfx::Display> GetAllDisplays() const = 0;
  73
  74   // Returns the display nearest the specified window.
  75   // If the window is NULL or the window is not rooted to a display this will
  76   // return the primary display.
  77   virtual gfx::Display GetDisplayNearestWindow(NativeView view) const = 0;
  78
  79   // Returns the display nearest the specified point. |point| should be in DIPs.
  80   virtual gfx::Display GetDisplayNearestPoint(
  81       const gfx::Point& point) const = 0;
  82
  83   // Returns the display that most closely intersects the provided bounds.
  84   virtual gfx::Display GetDisplayMatching(
  85       const gfx::Rect& match_rect) const = 0;
  86
  87   // Returns the primary display.
  88   virtual gfx::Display GetPrimaryDisplay() const = 0;
  89
  90   // Adds/Removes display observers.
  91   virtual void AddObserver(DisplayObserver* observer) = 0;
  92   virtual void RemoveObserver(DisplayObserver* observer) = 0;
  93
  94  private:
  95   DISALLOW_COPY_AND_ASSIGN(Screen);
  96 };
  97
  98 Screen* CreateNativeScreen();
  99
 100 }  // namespace gfx
 101
 102 #endif  // UI_GFX_SCREEN_H_