content/browser/renderer_host/legacy_render_widget_host_win.h

   1 // Copyright (c) 2014 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 CONTENT_BROWSER_RENDERER_HOST_LEGACY_RENDER_WIDGET_HOST_WIN_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_LEGACY_RENDER_WIDGET_HOST_WIN_H_
   7
   8 #include <atlbase.h>
   9 #include <atlwin.h>
  10 #include <atlcrack.h>
  11 #include <oleacc.h>
  12
  13 #include "base/basictypes.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/win/scoped_comptr.h"
  16 #include "content/common/content_export.h"
  17 #include "ui/gfx/geometry/rect.h"
  18
  19 namespace gfx {
  20 namespace win {
  21 class DirectManipulationHelper;
  22 }  // namespace win
  23 }  // namespace gfx
  24
  25 namespace ui {
  26 class WindowEventTarget;
  27 }
  28
  29 namespace content {
  30 class RenderWidgetHostViewAura;
  31
  32 // Reasons for the existence of this class outlined below:-
  33 // 1. Some screen readers expect every tab / every unique web content container
  34 //    to be in its own HWND with class name Chrome_RenderWidgetHostHWND.
  35 //    With Aura there is one main HWND which comprises the whole browser window
  36 //    or the whole desktop. So, we need a fake HWND with the window class as
  37 //    Chrome_RenderWidgetHostHWND as the root of the accessibility tree for
  38 //    each tab.
  39 // 2. There are legacy drivers for trackpads/trackpoints which have special
  40 //    code for sending mouse wheel and scroll events to the
  41 //    Chrome_RenderWidgetHostHWND window.
  42 // 3. Windowless NPAPI plugins like Flash and Silverlight which expect the
  43 //    container window to have the same bounds as the web page. In Aura, the
  44 //    default container window is the whole window which includes the web page
  45 //    WebContents, etc. This causes the plugin mouse event calculations to
  46 //    fail.
  47 //    We should look to get rid of this code when all of the above are fixed.
  48
  49 // This class implements a child HWND with the same size as the content area,
  50 // that delegates its accessibility implementation to the root of the
  51 // BrowserAccessibilityManager tree. This HWND is hooked up as the parent of
  52 // the root object in the BrowserAccessibilityManager tree, so when any
  53 // accessibility client calls ::WindowFromAccessibleObject, they get this
  54 // HWND instead of the DesktopWindowTreeHostWin.
  55 class CONTENT_EXPORT LegacyRenderWidgetHostHWND
  56     : public ATL::CWindowImpl<LegacyRenderWidgetHostHWND,
  57                               NON_EXPORTED_BASE(ATL::CWindow),
  58                               ATL::CWinTraits<WS_CHILD> > {
  59  public:
  60   DECLARE_WND_CLASS_EX(L"Chrome_RenderWidgetHostHWND", CS_DBLCLKS, 0);
  61
  62   typedef ATL::CWindowImpl<LegacyRenderWidgetHostHWND,
  63                            NON_EXPORTED_BASE(ATL::CWindow),
  64                            ATL::CWinTraits<WS_CHILD> > Base;
  65
  66   // Creates and returns an instance of the LegacyRenderWidgetHostHWND class on
  67   // successful creation of a child window parented to the parent window passed
  68   // in.
  69   static LegacyRenderWidgetHostHWND* Create(HWND parent);
  70
  71   // Destroys the HWND managed by this class.
  72   void Destroy();
  73
  74   BEGIN_MSG_MAP_EX(LegacyRenderWidgetHostHWND)
  75     MESSAGE_HANDLER_EX(WM_GETOBJECT, OnGetObject)
  76     MESSAGE_RANGE_HANDLER(WM_KEYFIRST, WM_KEYLAST, OnKeyboardRange)
  77     MESSAGE_HANDLER_EX(WM_PAINT, OnPaint)
  78     MESSAGE_HANDLER_EX(WM_NCPAINT, OnNCPaint)
  79     MESSAGE_HANDLER_EX(WM_ERASEBKGND, OnEraseBkGnd)
  80     MESSAGE_RANGE_HANDLER(WM_MOUSEFIRST, WM_MOUSELAST, OnMouseRange)
  81     MESSAGE_HANDLER_EX(WM_MOUSELEAVE, OnMouseLeave)
  82     MESSAGE_HANDLER_EX(WM_MOUSEACTIVATE, OnMouseActivate)
  83     MESSAGE_HANDLER_EX(WM_SETCURSOR, OnSetCursor)
  84     MESSAGE_HANDLER_EX(WM_TOUCH, OnTouch)
  85     MESSAGE_HANDLER_EX(WM_HSCROLL, OnScroll)
  86     MESSAGE_HANDLER_EX(WM_VSCROLL, OnScroll)
  87     MESSAGE_HANDLER_EX(WM_NCHITTEST, OnNCHitTest)
  88     MESSAGE_RANGE_HANDLER(WM_NCMOUSEMOVE, WM_NCXBUTTONDBLCLK,
  89                           OnMouseRange)
  90     MESSAGE_HANDLER_EX(WM_NCCALCSIZE, OnNCCalcSize)
  91     MESSAGE_HANDLER_EX(WM_SIZE, OnSize)
  92     MESSAGE_HANDLER_EX(WM_WINDOWPOSCHANGED, OnWindowPosChanged)
  93   END_MSG_MAP()
  94
  95   HWND hwnd() { return m_hWnd; }
  96
  97   // Called when the child window is to be reparented to a new window.
  98   // The |parent| parameter contains the new parent window.
  99   void UpdateParent(HWND parent);
 100   HWND GetParent();
 101
 102   IAccessible* window_accessible() { return window_accessible_.get(); }
 103
 104   // Functions to show and hide the window.
 105   void Show();
 106   void Hide();
 107
 108   // Resizes the window to the bounds passed in.
 109   void SetBounds(const gfx::Rect& bounds);
 110
 111   // The pointer to the containing RenderWidgetHostViewAura instance is passed
 112   // here.
 113   void set_host(RenderWidgetHostViewAura* host) {
 114     host_ = host;
 115   }
 116
 117  protected:
 118   void OnFinalMessage(HWND hwnd) override;
 119
 120  private:
 121   explicit LegacyRenderWidgetHostHWND(HWND parent);
 122   ~LegacyRenderWidgetHostHWND() override;
 123
 124   bool Init();
 125
 126   // Returns the target to which the windows input events are forwarded.
 127   static ui::WindowEventTarget* GetWindowEventTarget(HWND parent);
 128
 129   LRESULT OnEraseBkGnd(UINT message, WPARAM w_param, LPARAM l_param);
 130   LRESULT OnGetObject(UINT message, WPARAM w_param, LPARAM l_param);
 131   LRESULT OnKeyboardRange(UINT message, WPARAM w_param, LPARAM l_param,
 132                           BOOL& handled);
 133   LRESULT OnMouseLeave(UINT message, WPARAM w_param, LPARAM l_param);
 134   LRESULT OnMouseRange(UINT message, WPARAM w_param, LPARAM l_param,
 135                        BOOL& handled);
 136   LRESULT OnMouseActivate(UINT message, WPARAM w_param, LPARAM l_param);
 137   LRESULT OnTouch(UINT message, WPARAM w_param, LPARAM l_param);
 138   LRESULT OnScroll(UINT message, WPARAM w_param, LPARAM l_param);
 139   LRESULT OnNCHitTest(UINT message, WPARAM w_param, LPARAM l_param);
 140
 141   LRESULT OnNCPaint(UINT message, WPARAM w_param, LPARAM l_param);
 142   LRESULT OnPaint(UINT message, WPARAM w_param, LPARAM l_param);
 143   LRESULT OnSetCursor(UINT message, WPARAM w_param, LPARAM l_param);
 144   LRESULT OnNCCalcSize(UINT message, WPARAM w_param, LPARAM l_param);
 145   LRESULT OnSize(UINT message, WPARAM w_param, LPARAM l_param);
 146   LRESULT OnWindowPosChanged(UINT message, WPARAM w_param, LPARAM l_param);
 147
 148   base::win::ScopedComPtr<IAccessible> window_accessible_;
 149
 150   // Set to true if we turned on mouse tracking.
 151   bool mouse_tracking_enabled_;
 152
 153   RenderWidgetHostViewAura* host_;
 154
 155   // This class provides functionality to register the legacy window as a
 156   // Direct Manipulation consumer. This allows us to support smooth scroll
 157   // in Chrome on Windows 10.
 158   scoped_ptr<gfx::win::DirectManipulationHelper> direct_manipulation_helper_;
 159
 160   DISALLOW_COPY_AND_ASSIGN(LegacyRenderWidgetHostHWND);
 161 };
 162
 163 }  // namespace content
 164
 165 #endif  // CONTENT_BROWSER_RENDERER_HOST_LEGACY_RENDER_WIDGET_HOST_WIN_H_
 166