Allow saving the drawing sample canvas to a file or clipboard.

This allows to test wxMemoryDC and, under MSW, wxMetafileDC and also can be
used to compare the output of different versions of the sample (possibly from
different ports, too).

Closes #13327.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@68305 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/drawing/drawing.cpp

@@ -37,6 +37,7 @@
 #include "wx/overlay.h"
 #include "wx/graphics.h"
 #include "wx/filename.h"
+#include "wx/metafile.h"
 
 #define TEST_CAIRO_EVERYWHERE 0
 
@@ -101,6 +102,8 @@ public:
 #if wxUSE_GRAPHICS_CONTEXT
     void OnGraphicContext(wxCommandEvent& event);
 #endif
+    void OnCopy(wxCommandEvent& event);
+    void OnSave(wxCommandEvent& event);
     void OnShow(wxCommandEvent &event);
     void OnOption(wxCommandEvent &event);
 
@@ -146,6 +149,7 @@ public:
 #if wxUSE_GRAPHICS_CONTEXT
     void UseGraphicContext(bool use) { m_useContext = use; Refresh(); }
 #endif
+    template <typename T> void Draw(T& dc);
 
 protected:
     enum DrawMode
@@ -224,6 +228,8 @@ enum
 #if wxUSE_GRAPHICS_CONTEXT
     File_GraphicContext,
 #endif
+    File_Copy,
+    File_Save,
 
     MenuOption_First,
 
@@ -359,6 +365,9 @@ bool MyApp::OnInit()
         // still continue, the sample can be used without images too if they're
         // missing for whatever reason
     }
+#if wxUSE_LIBPNG
+      wxImage::AddHandler( new wxPNGHandler );
+#endif
 
     return true;
 }
@@ -1485,7 +1494,12 @@ extern wxGraphicsRenderer* gCairoRenderer;
 void MyCanvas::OnPaint(wxPaintEvent &WXUNUSED(event))
 {
     wxPaintDC pdc(this);
+    Draw(pdc);
+}
 
+template <typename T>
+void MyCanvas::Draw(T& pdc)
+{
 #if wxUSE_GRAPHICS_CONTEXT
 #if TEST_CAIRO_EVERYWHERE
     wxGCDC gdc;
@@ -1691,6 +1705,8 @@ BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 #if wxUSE_GRAPHICS_CONTEXT
     EVT_MENU      (File_GraphicContext, MyFrame::OnGraphicContext)
 #endif
+    EVT_MENU      (File_Copy,     MyFrame::OnCopy)
+    EVT_MENU      (File_Save,     MyFrame::OnSave)
 
     EVT_MENU_RANGE(MenuShow_First,   MenuShow_Last,   MyFrame::OnShow)
 
@@ -1719,7 +1735,7 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
 #if wxUSE_GRAPHICS_CONTEXT
     menuFile->Append(File_ShowAlpha, wxT("&Alpha screen\tF10"));
 #endif
-    menuFile->Append(File_ShowSplines, wxT("&Splines screen\tF11"));
+    menuFile->Append(File_ShowSplines, wxT("Spl&ines screen\tF11"));
     menuFile->Append(File_ShowGradients, wxT("&Gradients screen\tF12"));
 #if wxUSE_GRAPHICS_CONTEXT
      menuFile->Append(File_ShowGraphics, wxT("&Graphics screen"));
@@ -1730,6 +1746,11 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
     menuFile->AppendCheckItem(File_GraphicContext, wxT("&Use GraphicContext\tCtrl-Y"), wxT("Use GraphicContext"));
 #endif
     menuFile->AppendSeparator();
+#if wxUSE_METAFILE && defined(wxMETAFILE_IS_ENH)
+    menuFile->Append(File_Copy, wxT("Copy to clipboard"));
+#endif
+    menuFile->Append(File_Save, wxT("&Save...\tCtrl-S"), wxT("Save drawing to file"));
+    menuFile->AppendSeparator();
     menuFile->Append(File_About, wxT("&About...\tCtrl-A"), wxT("Show about dialog"));
     menuFile->AppendSeparator();
     menuFile->Append(File_Quit, wxT("E&xit\tAlt-X"), wxT("Quit this program"));
@@ -1836,6 +1857,38 @@ void MyFrame::OnGraphicContext(wxCommandEvent& event)
 }
 #endif
 
+void MyFrame::OnCopy(wxCommandEvent& WXUNUSED(event))
+{
+#if wxUSE_METAFILE && defined(wxMETAFILE_IS_ENH)
+    wxMetafileDC dc;
+    if (!dc.IsOk())
+        return;
+    m_canvas->Draw(dc);
+    wxMetafile *mf = dc.Close();
+    if (!mf)
+        return;
+    mf->SetClipboard();
+    delete mf;
+#endif
+}
+
+void MyFrame::OnSave(wxCommandEvent& WXUNUSED(event))
+{
+    wxFileDialog dlg(this, wxT("Save as bitmap"), wxT(""), wxT(""),
+#if wxUSE_LIBPNG
+                     wxT("PNG image (*.png)|*.png;*.PNG|")
+#endif
+                     wxT("Bitmap image (*.bmp)|*.bmp;*.BMP"),
+                     wxFD_SAVE | wxFD_OVERWRITE_PROMPT);
+    if (dlg.ShowModal() == wxID_OK)
+    {
+        wxBitmap bmp(500, 800);
+        wxMemoryDC mdc(bmp);
+        m_canvas->Draw(mdc);
+        bmp.ConvertToImage().SaveFile(dlg.GetPath());
+    }
+}
+
 void MyFrame::OnShow(wxCommandEvent& event)
 {
     m_canvas->ToShow(event.GetId());