Add wxGraphicsContext::GetWindow()

This method allows to retrieve the window this context is associated
with, if any.

Add "wxWindow*" argument to wxGraphicsContext ctor and provide the
window pointer to it when available, i.e. when creating the context from
a wxWindow directly or from wxWindowDC, which is also associated with a
window, in platform-specific code.

No real changes yet.

docs/changes.txt

@@ -128,6 +128,7 @@ All (GUI):
 - Add wxGrid::SetCornerLabelValue() (Pavel Kalugin).
 - Add strikethrough support for fonts defined in XRC.
 - Add wxDisplay::GetPPI().
+- Add wxGraphicsContext::GetWindow().
 
 wxGTK:
 

include/wx/graphics.h

@@ -452,7 +452,7 @@ private:
 class WXDLLIMPEXP_CORE wxGraphicsContext : public wxGraphicsObject
 {
 public:
-    wxGraphicsContext(wxGraphicsRenderer* renderer);
+    wxGraphicsContext(wxGraphicsRenderer* renderer, wxWindow* window = NULL);
 
     virtual ~wxGraphicsContext();
 
@@ -490,6 +490,9 @@ public:
     // create a context that can be used for measuring texts only, no drawing allowed
     static wxGraphicsContext * Create();
 
+    // Return the window this context is associated with, if any.
+    wxWindow* GetWindow() const { return m_window; }
+
     // begin a new document (relevant only for printing / pdf etc) if there is a progress dialog, message will be shown
     virtual bool StartDoc( const wxString& message );
 
@@ -788,6 +791,12 @@ protected:
                                          wxDouble angle,
                                          const wxGraphicsBrush& backgroundBrush);
 
+private:
+    // The associated window, if any, i.e. if one was passed directly to
+    // Create() or the associated window of the wxDC this context was created
+    // from.
+    wxWindow* const m_window;
+
     wxDECLARE_NO_COPY_CLASS(wxGraphicsContext);
     wxDECLARE_ABSTRACT_CLASS(wxGraphicsContext);
 };

interface/wx/graphics.h

@@ -1095,6 +1095,19 @@ public:
     */
     virtual void GetDPI( wxDouble* dpiX, wxDouble* dpiY);
 
+    /**
+        Returns the associated window if any.
+
+        If this context was created using Create() overload taking wxWindow or
+        wxWindowDC, this method returns the corresponding window. Otherwise
+        returns @NULL.
+
+        @return A possibly @NULL window pointer.
+
+        @since 3.1.2
+     */
+    wxWindow* GetWindow() const;
+
     /** @}
     */
 

src/common/graphcmn.cpp

@@ -565,12 +565,14 @@ void * wxGraphicsBitmap::GetNativeBitmap() const
 wxIMPLEMENT_ABSTRACT_CLASS(wxGraphicsContext, wxObject);
 
 
-wxGraphicsContext::wxGraphicsContext(wxGraphicsRenderer* renderer) :
+wxGraphicsContext::wxGraphicsContext(wxGraphicsRenderer* renderer,
-    wxGraphicsObject(renderer),
+                                     wxWindow* window)
+    : wxGraphicsObject(renderer),
       m_antialias(wxANTIALIAS_DEFAULT),
       m_composition(wxCOMPOSITION_OVER),
       m_interpolation(wxINTERPOLATION_DEFAULT),
-      m_enableOffset(false)
+      m_enableOffset(false),
+      m_window(window)
 {
 }
 

src/generic/graphicc.cpp

@@ -1830,7 +1830,7 @@ wxCairoContext::wxCairoContext( wxGraphicsRenderer* renderer, const wxPrinterDC&
 #endif
 
 wxCairoContext::wxCairoContext( wxGraphicsRenderer* renderer, const wxWindowDC& dc )
-: wxGraphicsContext(renderer)
+: wxGraphicsContext(renderer, dc.GetWindow())
 {
     int width, height;
     dc.GetSize( &width, &height );
@@ -2244,7 +2244,7 @@ wxCairoContext::wxCairoContext( wxGraphicsRenderer* renderer, cairo_t *context )
 }
 
 wxCairoContext::wxCairoContext( wxGraphicsRenderer* renderer, wxWindow *window)
-    : wxGraphicsContext(renderer)
+    : wxGraphicsContext(renderer, window)
 #ifdef __WXMSW__
     , m_mswWindowHDC(GetHwndOf(window))
 #endif

src/msw/graphics.cpp

@@ -358,7 +358,7 @@ class wxGDIPlusContext : public wxGraphicsContext
 public:
     wxGDIPlusContext( wxGraphicsRenderer* renderer, const wxDC& dc );
     wxGDIPlusContext( wxGraphicsRenderer* renderer, HDC hdc, wxDouble width, wxDouble height );
-    wxGDIPlusContext( wxGraphicsRenderer* renderer, HWND hwnd );
+    wxGDIPlusContext( wxGraphicsRenderer* renderer, HWND hwnd, wxWindow* window = NULL);
     wxGDIPlusContext( wxGraphicsRenderer* renderer, Graphics* gr);
     wxGDIPlusContext(wxGraphicsRenderer* renderer);
 
@@ -1647,7 +1647,7 @@ wxGDIPlusContext::wxGDIPlusContext( wxGraphicsRenderer* renderer, HDC hdc, wxDou
 }
 
 wxGDIPlusContext::wxGDIPlusContext( wxGraphicsRenderer* renderer, const wxDC& dc )
-    : wxGraphicsContext(renderer)
+    : wxGraphicsContext(renderer, dc.GetWindow())
 {
     wxMSWDCImpl *msw = wxDynamicCast( dc.GetImpl() , wxMSWDCImpl );
     HDC hdc = (HDC) msw->GetHDC();
@@ -1656,8 +1656,10 @@ wxGDIPlusContext::wxGDIPlusContext( wxGraphicsRenderer* renderer, const wxDC& dc
     Init(new Graphics(hdc), sz.x, sz.y);
 }
 
-wxGDIPlusContext::wxGDIPlusContext( wxGraphicsRenderer* renderer, HWND hwnd  )
+wxGDIPlusContext::wxGDIPlusContext( wxGraphicsRenderer* renderer,
-    : wxGraphicsContext(renderer)
+                                    HWND hwnd,
+                                    wxWindow* window )
+    : wxGraphicsContext(renderer, window)
 {
     RECT rect = wxGetWindowRect(hwnd);
     Init(new Graphics(hwnd), rect.right - rect.left, rect.bottom - rect.top);
@@ -2492,7 +2494,7 @@ wxGraphicsContext * wxGDIPlusRenderer::CreateContextFromNativeHDC(WXHDC dc)
 wxGraphicsContext * wxGDIPlusRenderer::CreateContext( wxWindow* window )
 {
     ENSURE_LOADED_OR_RETURN(NULL);
-    return new wxGDIPlusContext(this, (HWND) window->GetHWND() );
+    return new wxGDIPlusContext(this, (HWND) window->GetHWND(), window );
 }
 
 // Path

src/msw/graphicsd2d.cpp

@@ -3400,9 +3400,19 @@ public:
 class wxD2DContext : public wxGraphicsContext, wxD2DResourceManager
 {
 public:
-    wxD2DContext(wxGraphicsRenderer* renderer, ID2D1Factory* direct2dFactory, HWND hwnd);
+    // Create the context for the given HWND, which may be associated (if it's
+    // non-null) with the given wxWindow.
+    wxD2DContext(wxGraphicsRenderer* renderer,
+                 ID2D1Factory* direct2dFactory,
+                 HWND hwnd,
+                 wxWindow* window = NULL);
 
-    wxD2DContext(wxGraphicsRenderer* renderer, ID2D1Factory* direct2dFactory, HDC hdc, const wxSize& dcSize,
+    // Create the context for the given HDC which may be associated (if it's
+    // non-null) with the given wxDC.
+    wxD2DContext(wxGraphicsRenderer* renderer,
+                 ID2D1Factory* direct2dFactory,
+                 HDC hdc,
+                 const wxDC* dc = NULL,
                  D2D1_ALPHA_MODE alphaMode = D2D1_ALPHA_MODE_IGNORE);
 
 #if wxUSE_IMAGE
@@ -3550,8 +3560,11 @@ private:
 // wxD2DContext implementation
 //-----------------------------------------------------------------------------
 
-wxD2DContext::wxD2DContext(wxGraphicsRenderer* renderer, ID2D1Factory* direct2dFactory, HWND hwnd) :
+wxD2DContext::wxD2DContext(wxGraphicsRenderer* renderer,
-    wxGraphicsContext(renderer), m_direct2dFactory(direct2dFactory),
+                           ID2D1Factory* direct2dFactory,
+                           HWND hwnd,
+                           wxWindow* window) :
+    wxGraphicsContext(renderer, window), m_direct2dFactory(direct2dFactory),
 #if wxD2D_DEVICE_CONTEXT_SUPPORTED
     m_renderTargetHolder(new wxD2DDeviceContextResourceHolder(direct2dFactory, hwnd))
 #else
@@ -3564,13 +3577,21 @@ wxD2DContext::wxD2DContext(wxGraphicsRenderer* renderer, ID2D1Factory* direct2dF
     Init();
 }
 
-wxD2DContext::wxD2DContext(wxGraphicsRenderer* renderer, ID2D1Factory* direct2dFactory, HDC hdc,
+wxD2DContext::wxD2DContext(wxGraphicsRenderer* renderer,
-                           const wxSize& dcSize, D2D1_ALPHA_MODE alphaMode) :
+                           ID2D1Factory* direct2dFactory,
-    wxGraphicsContext(renderer), m_direct2dFactory(direct2dFactory),
+                           HDC hdc,
+                           const wxDC* dc,
+                           D2D1_ALPHA_MODE alphaMode) :
+    wxGraphicsContext(renderer, dc->GetWindow()), m_direct2dFactory(direct2dFactory),
     m_renderTargetHolder(new wxD2DDCRenderTargetResourceHolder(direct2dFactory, hdc, alphaMode))
 {
+    if ( dc )
+    {
+        const wxSize dcSize = dc->GetSize();
         m_width = dcSize.GetWidth();
         m_height = dcSize.GetHeight();
+    }
+
     Init();
 }
 
@@ -4531,7 +4552,7 @@ wxD2DRenderer::~wxD2DRenderer()
 
 wxGraphicsContext* wxD2DRenderer::CreateContext(const wxWindowDC& dc)
 {
-    return new wxD2DContext(this, m_direct2dFactory, dc.GetHDC(), dc.GetSize());
+    return new wxD2DContext(this, m_direct2dFactory, dc.GetHDC(), &dc);
 }
 
 wxGraphicsContext* wxD2DRenderer::CreateContext(const wxMemoryDC& dc)
@@ -4539,7 +4560,7 @@ wxGraphicsContext* wxD2DRenderer::CreateContext(const wxMemoryDC& dc)
     wxBitmap bmp = dc.GetSelectedBitmap();
     wxASSERT_MSG( bmp.IsOk(), wxS("Should select a bitmap before creating wxGraphicsContext") );
 
-    return new wxD2DContext(this, m_direct2dFactory, dc.GetHDC(), dc.GetSize(),
+    return new wxD2DContext(this, m_direct2dFactory, dc.GetHDC(), &dc,
                             bmp.HasAlpha() ? D2D1_ALPHA_MODE_PREMULTIPLIED : D2D1_ALPHA_MODE_IGNORE);
 }
 
@@ -4571,12 +4592,12 @@ wxGraphicsContext* wxD2DRenderer::CreateContextFromNativeWindow(void* window)
 
 wxGraphicsContext* wxD2DRenderer::CreateContextFromNativeHDC(WXHDC dc)
 {
-    return new wxD2DContext(this, m_direct2dFactory, (HDC)dc, wxSize(0, 0));
+    return new wxD2DContext(this, m_direct2dFactory, (HDC)dc);
 }
 
 wxGraphicsContext* wxD2DRenderer::CreateContext(wxWindow* window)
 {
-    return new wxD2DContext(this, m_direct2dFactory, (HWND)window->GetHWND());
+    return new wxD2DContext(this, m_direct2dFactory, (HWND)window->GetHWND(), window);
 }
 
 #if wxUSE_IMAGE

src/osx/carbon/graphics.cpp

@@ -1303,7 +1303,11 @@ bool wxMacCoreGraphicsPathData::Contains( wxDouble x, wxDouble y, wxPolygonFillM
 class WXDLLEXPORT wxMacCoreGraphicsContext : public wxGraphicsContext
 {
 public:
-    wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer, CGContextRef cgcontext, wxDouble width = 0, wxDouble height = 0 );
+    wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer,
+                              CGContextRef cgcontext,
+                              wxDouble width = 0,
+                              wxDouble height = 0,
+                              wxWindow* window = NULL );
 
     wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer, wxWindow* window );
 
@@ -1509,7 +1513,12 @@ void wxMacCoreGraphicsContext::Init()
     m_interpolation = wxINTERPOLATION_DEFAULT;
 }
 
-wxMacCoreGraphicsContext::wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer, CGContextRef cgcontext, wxDouble width, wxDouble height ) : wxGraphicsContext(renderer)
+wxMacCoreGraphicsContext::wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer,
+                                                    CGContextRef cgcontext,
+                                                    wxDouble width,
+                                                    wxDouble height,
+                                                    wxWindow* window )
+    : wxGraphicsContext(renderer, window)
 {
     Init();
     SetNativeContext(cgcontext);
@@ -1518,7 +1527,9 @@ wxMacCoreGraphicsContext::wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer
     m_initTransform = m_cgContext ? CGContextGetCTM(m_cgContext) : CGAffineTransformIdentity;
 }
 
-wxMacCoreGraphicsContext::wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer, wxWindow* window ): wxGraphicsContext(renderer)
+wxMacCoreGraphicsContext::wxMacCoreGraphicsContext( wxGraphicsRenderer* renderer,
+                                                    wxWindow* window )
+    : wxGraphicsContext(renderer, window)
 {
     Init();
 
@@ -2694,27 +2705,19 @@ wxGraphicsRenderer* wxGraphicsRenderer::GetDefaultRenderer()
 
 wxGraphicsContext * wxMacCoreGraphicsRenderer::CreateContext( const wxWindowDC& dc )
 {
-    const wxDCImpl* impl = dc.GetImpl();
+    wxWindow* const win = dc.GetWindow();
-    wxWindowDCImpl *win_impl = wxDynamicCast( impl, wxWindowDCImpl );
+    wxCHECK_MSG( win, NULL, "Invalid wxWindowDC" );
-    if (win_impl)
-    {
-        int w, h;
-        win_impl->GetSize( &w, &h );
-        CGContextRef cgctx = 0;
 
-        wxASSERT_MSG(win_impl->GetWindow(), "Invalid wxWindow in wxMacCoreGraphicsRenderer::CreateContext");
+    const wxSize sz = win->GetSize();
-        if (win_impl->GetWindow())
-            cgctx =  (CGContextRef)(win_impl->GetWindow()->MacGetCGContextRef());
 
     // having a cgctx being NULL is fine (will be created on demand)
     // this is the case for all wxWindowDCs except wxPaintDC
+    CGContextRef cgctx = (CGContextRef)(win->MacGetCGContextRef());
     wxMacCoreGraphicsContext *context =
-            new wxMacCoreGraphicsContext( this, cgctx, (wxDouble) w, (wxDouble) h );
+        new wxMacCoreGraphicsContext( this, cgctx, sz.x, sz.y, win );
     context->EnableOffset(dc.GetContentScaleFactor() < 2);
     return context;
 }
-    return NULL;
-}
 
 wxGraphicsContext * wxMacCoreGraphicsRenderer::CreateContext( const wxMemoryDC& dc )
 {