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/gfx_export.h"
  13 #include "ui/gfx/native_widget_types.h"
  14 #include "ui/gfx/point.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   static void SetScreenInstance(ScreenType type, Screen* instance);
  41
  42   // Returns the global screen for a particular type. Types other than _NATIVE
  43   // may be NULL.
  44   static Screen* GetScreenByType(ScreenType type);
  45
  46   // Sets the global ScreenTypeDelegate. May be left unset if the platform
  47   // uses only the _NATIVE ScreenType.
  48   static void SetScreenTypeDelegate(ScreenTypeDelegate* delegate);
  49
  50   Screen();
  51   virtual ~Screen();
  52
  53   // Returns the current absolute position of the mouse pointer.
  54   virtual gfx::Point GetCursorScreenPoint() = 0;
  55
  56   // Returns the window under the cursor.
  57   virtual gfx::NativeWindow GetWindowUnderCursor() = 0;
  58
  59   // Returns the window at the given screen coordinate |point|.
  60   virtual gfx::NativeWindow GetWindowAtScreenPoint(const gfx::Point& point) = 0;
  61
  62   // Returns the number of displays.
  63   // Mirrored displays are excluded; this method is intended to return the
  64   // number of distinct, usable displays.
  65   virtual int GetNumDisplays() const = 0;
  66
  67   // Returns the list of displays that are currently available.
  68   virtual std::vector<gfx::Display> GetAllDisplays() const = 0;
  69
  70   // Returns the display nearest the specified window.
  71   // If the window is NULL or the window is not rooted to a display this will
  72   // return the primary display.
  73   virtual gfx::Display GetDisplayNearestWindow(NativeView view) const = 0;
  74
  75   // Returns the display nearest the specified point.
  76   virtual gfx::Display GetDisplayNearestPoint(
  77       const gfx::Point& point) const = 0;
  78
  79   // Returns the display that most closely intersects the provided bounds.
  80   virtual gfx::Display GetDisplayMatching(
  81       const gfx::Rect& match_rect) const = 0;
  82
  83   // Returns the primary display.
  84   virtual gfx::Display GetPrimaryDisplay() const = 0;
  85
  86   // Adds/Removes display observers.
  87   virtual void AddObserver(DisplayObserver* observer) = 0;
  88   virtual void RemoveObserver(DisplayObserver* observer) = 0;
  89
  90  private:
  91   DISALLOW_COPY_AND_ASSIGN(Screen);
  92 };
  93
  94 Screen* CreateNativeScreen();
  95
  96 }  // namespace gfx
  97
  98 #endif  // UI_GFX_SCREEN_H_