Demonstrate storing wxImage to clipboard in image sample

samples/image/image.cpp

@@ -91,6 +91,8 @@ public:
 #if wxUSE_CLIPBOARD
     void OnCopy(wxCommandEvent& event);
     void OnPaste(wxCommandEvent& event);
+    void OnCopyImage(wxCommandEvent& evt);
+    void OnPasteImage(wxCommandEvent& evt);
 #endif // wxUSE_CLIPBOARD
 
     MyCanvas         *m_canvas;
@@ -124,8 +126,39 @@ class MyImageFrame : public wxFrame
 public:
     MyImageFrame(wxFrame *parent, const wxString& desc, const wxImage& image, double scale = 1.0)
     {
-        Create(parent, desc, wxBitmap(image, wxBITMAP_SCREEN_DEPTH, scale),
-            image.GetImageCount(desc));
+        // Retrieve image info
+        wxString info;
+        int xres, yres;
+        switch ( GetResolutionFromOptions(image, &xres, &yres) )
+        {
+            case wxIMAGE_RESOLUTION_NONE:
+                break;
+
+            case wxIMAGE_RESOLUTION_CM:
+                // convert to DPI
+                xres = wxRound(xres / 10.0 * inches2mm);
+                yres = wxRound(yres / 10.0 * inches2mm);
+                wxFALLTHROUGH;
+
+            case wxIMAGE_RESOLUTION_INCHES:
+                info = wxString::Format("DPI %i x %i", xres, yres);
+                break;
+
+            default:
+                wxFAIL_MSG("unexpected image resolution units");
+                break;
+        }
+
+        int numImages = desc.StartsWith("Clipboard") ? 1 : image.GetImageCount(desc);
+        if ( numImages > 1 )
+        {
+            if ( !info.empty() )
+                info += ", ";
+
+            info += wxString::Format("%d images", numImages);
+        }
+
+        Create(parent, desc, wxBitmap(image, wxBITMAP_SCREEN_DEPTH, scale), info);
     }
 
     MyImageFrame(wxFrame *parent, const wxString& desc, const wxBitmap& bitmap)
@@ -137,7 +170,7 @@ private:
     bool Create(wxFrame *parent,
                 const wxString& desc,
                 const wxBitmap& bitmap,
-                int numImages = 1)
+                wxString info = wxString())
     {
         if ( !wxFrame::Create(parent, wxID_ANY,
                               wxString::Format("Image from %s", desc),
@@ -169,8 +202,7 @@ private:
         mbar->Check(ID_PAINT_BG, true);
 
         CreateStatusBar(2);
-        if ( numImages != 1 )
-            SetStatusText(wxString::Format("%d images", numImages), 1);
+        SetStatusText(info, 1);
 
         SetClientSize(bitmap.GetWidth(), bitmap.GetHeight());
 
@@ -439,6 +471,41 @@ private:
         Refresh();
     }
 
+    // This is a copy of protected wxImageHandler::GetResolutionFromOptions()
+    static wxImageResolution GetResolutionFromOptions(const wxImage& image, int* x, int* y)
+    {
+        wxCHECK_MSG(x && y, wxIMAGE_RESOLUTION_NONE, wxT("NULL pointer"));
+
+        if ( image.HasOption(wxIMAGE_OPTION_RESOLUTIONX) &&
+            image.HasOption(wxIMAGE_OPTION_RESOLUTIONY) )
+        {
+            *x = image.GetOptionInt(wxIMAGE_OPTION_RESOLUTIONX);
+            *y = image.GetOptionInt(wxIMAGE_OPTION_RESOLUTIONY);
+        }
+        else if ( image.HasOption(wxIMAGE_OPTION_RESOLUTION) )
+        {
+            *x =
+            *y = image.GetOptionInt(wxIMAGE_OPTION_RESOLUTION);
+        }
+        else // no resolution options specified
+        {
+            *x =
+            *y = 0;
+
+            return wxIMAGE_RESOLUTION_NONE;
+        }
+
+        // get the resolution unit too
+        int resUnit = image.GetOptionInt(wxIMAGE_OPTION_RESOLUTIONUNIT);
+        if ( !resUnit )
+        {
+            // this is the default
+            resUnit = wxIMAGE_RESOLUTION_INCHES;
+        }
+
+        return (wxImageResolution)resUnit;
+    }
+
     wxBitmap m_bitmap;
     double m_zoom;
 
@@ -631,7 +698,9 @@ enum
     ID_INFO,
     ID_SHOWRAW,
     ID_GRAPHICS,
-    ID_SHOWTHUMBNAIL
+    ID_SHOWTHUMBNAIL,
+    ID_COPY_IMAGE,
+    ID_PASTE_IMAGE
 };
 
 wxIMPLEMENT_DYNAMIC_CLASS( MyFrame, wxFrame );
@@ -651,6 +720,8 @@ wxBEGIN_EVENT_TABLE(MyFrame, wxFrame)
 #if wxUSE_CLIPBOARD
     EVT_MENU(wxID_COPY, MyFrame::OnCopy)
     EVT_MENU(wxID_PASTE, MyFrame::OnPaste)
+    EVT_MENU(ID_COPY_IMAGE, MyFrame::OnCopyImage)
+    EVT_MENU(ID_PASTE_IMAGE, MyFrame::OnPasteImage)
 #endif // wxUSE_CLIPBOARD
     EVT_UPDATE_UI(ID_NEW_HIDPI, MyFrame::OnUpdateNewFrameHiDPI)
 wxEND_EVENT_TABLE()
@@ -686,8 +757,11 @@ MyFrame::MyFrame()
 
 #if wxUSE_CLIPBOARD
     wxMenu *menuClipboard = new wxMenu;
-    menuClipboard->Append(wxID_COPY, "&Copy test image\tCtrl-C");
-    menuClipboard->Append(wxID_PASTE, "&Paste image\tCtrl-V");
+    menuClipboard->Append(wxID_COPY, "&Copy test image as wxBitmap\tCtrl-C");
+    menuClipboard->Append(wxID_PASTE, "&Paste image as wxBitmap\tCtrl-V");
+    menuClipboard->AppendSeparator();
+    menuClipboard->Append(ID_COPY_IMAGE, "Copy image as wxImage");
+    menuClipboard->Append(ID_PASTE_IMAGE, "Paste image as wxImage");
     menu_bar->Append(menuClipboard, "&Clipboard");
 #endif // wxUSE_CLIPBOARD
 
@@ -945,6 +1019,38 @@ void MyFrame::OnPaste(wxCommandEvent& WXUNUSED(event))
     wxTheClipboard->Close();
 }
 
+void MyFrame::OnCopyImage(wxCommandEvent& WXUNUSED(evt))
+{
+    wxImage img;
+    wxString filename = LoadUserImage(img);
+    if ( filename.empty() )
+        return;
+
+    wxImageDataObject* dobjImage = new wxImageDataObject;
+    dobjImage->SetImage(img);
+
+    wxClipboardLocker clipOpener;
+    if ( !wxTheClipboard->SetData(dobjImage) )
+    {
+        wxLogError("Failed to copy wxImage to clipboard");
+    }
+}
+
+void MyFrame::OnPasteImage(wxCommandEvent& WXUNUSED(evt))
+{
+    wxImageDataObject dobjImage;
+
+    wxClipboardLocker clipOpener;
+    if ( !wxTheClipboard->GetData(dobjImage) )
+    {
+        wxLogMessage("No wxImage data in the clipboard");
+    }
+    else
+    {
+        new MyImageFrame(this, "Clipboard (wxImage)", dobjImage.GetImage());
+    }
+}
+
 #endif // wxUSE_CLIPBOARD
 
 void MyFrame::OnThumbnail( wxCommandEvent &WXUNUSED(event) )