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 "base/basictypes.h"
   9 #include "ui/base/ui_export.h"
  10 #include "ui/gfx/display.h"
  11 #include "ui/gfx/native_widget_types.h"
  12 #include "ui/gfx/point.h"
  13 #include "ui/gfx/screen_type_delegate.h"
  14
  15 namespace gfx {
  16 class DisplayObserver;
  17 class Rect;
  18
  19 // A utility class for getting various info about screen size, displays,
  20 // cursor position, etc.
  21 class UI_EXPORT Screen {
  22  public:
  23   // Retrieves the Screen that the specified NativeView belongs to. A value of
  24   // NULL is treated as |SCREEN_TYPE_NATIVE|.
  25   static Screen* GetScreenFor(NativeView view);
  26
  27   // Returns the SCREEN_TYPE_NATIVE Screen. This should be used with caution,
  28   // as it is likely to be incorrect for code that runs on Windows.
  29   static Screen* GetNativeScreen();
  30
  31   // Sets the global screen for a particular screen type. Only the _NATIVE
  32   // ScreenType must be provided.
  33   static void SetScreenInstance(ScreenType type, Screen* instance);
  34
  35   // Returns the global screen for a particular type. Types other than _NATIVE
  36   // may be NULL.
  37   static Screen* GetScreenByType(ScreenType type);
  38
  39   // Sets the global ScreenTypeDelegate. May be left unset if the platform
  40   // uses only the _NATIVE ScreenType.
  41   static void SetScreenTypeDelegate(ScreenTypeDelegate* delegate);
  42
  43   Screen();
  44   virtual ~Screen();
  45
  46   // Returns true if DIP is enabled.
  47   virtual bool IsDIPEnabled() = 0;
  48
  49   // Returns the current absolute position of the mouse pointer.
  50   virtual gfx::Point GetCursorScreenPoint() = 0;
  51
  52   // Returns the window under the cursor.
  53   virtual gfx::NativeWindow GetWindowAtCursorScreenPoint() = 0;
  54
  55   // Returns the number of displays.
  56   // Mirrored displays are excluded; this method is intended to return the
  57   // number of distinct, usable displays.
  58   virtual int GetNumDisplays() = 0;
  59
  60   // Returns the display nearest the specified window.
  61   virtual gfx::Display GetDisplayNearestWindow(NativeView view) const = 0;
  62
  63   // Returns the the display nearest the specified point.
  64   virtual gfx::Display GetDisplayNearestPoint(
  65       const gfx::Point& point) const = 0;
  66
  67   // Returns the display that most closely intersects the provided bounds.
  68   virtual gfx::Display GetDisplayMatching(
  69       const gfx::Rect& match_rect) const = 0;
  70
  71   // Returns the primary display.
  72   virtual gfx::Display GetPrimaryDisplay() const = 0;
  73
  74   // Adds/Removes display observers.
  75   virtual void AddObserver(DisplayObserver* observer) = 0;
  76   virtual void RemoveObserver(DisplayObserver* observer) = 0;
  77
  78  private:
  79   DISALLOW_COPY_AND_ASSIGN(Screen);
  80 };
  81
  82 Screen* CreateNativeScreen();
  83
  84 }  // namespace gfx
  85
  86 #endif  // UI_GFX_SCREEN_H_