1. wxDropTarget::OnData() returns wxDragResult now, not bool

2. fixed assert failure in wxMSW::wxListBox
3. wxFileHistory automatically deletes non existinf files from menu
4. wxDropTarget coordinates are client (and not screen) under MSW too
5. wxConvertBitmapToDib and vice versa seem to work!
6. client data field if filled by wxListBox and wxChoice and it's also deleted
   (this just wasn't done before!)


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@4153 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/ole/dataobj.cpp

@@ -463,6 +463,12 @@ STDMETHODIMP wxIDataObject::SetData(FORMATETC *pformatetc,
                         size = 0;
                         break;
 
+                    case CF_DIB:
+                        // the handler will calculate size itself (it's too
+                        // complicated to do it here)
+                        size = 0;
+                        break;
+
                     default:
                         {
                             // we suppose that the size precedes the data
@@ -944,64 +950,122 @@ bool wxFileDataObject::SetData(size_t WXUNUSED(size), const void *pData)
 // private functions
 // ----------------------------------------------------------------------------
 
-// otherwise VC++ would give here:
-//  "local variable 'bi' may be used without having been initialized"
-// even though in fact it may not
-#ifdef __VISUALC__
-    #pragma warning(disable:4701)
-#endif // __VISUALC__
+static size_t wxGetNumOfBitmapColors(size_t bitsPerPixel)
+{
+    switch ( bitsPerPixel )
+    {
+        case 1:
+            // monochrome bitmap, 2 entries
+            return 2;
+
+        case 4:
+            return 16;
+
+        case 8:
+            return 256;
+
+        case 24:
+            // may be used with 24bit bitmaps, but we don't use it here - fall
+            // through
+
+        case 16:
+        case 32:
+            // bmiColors not used at all with these bitmaps
+            return 0;
+
+        default:
+            wxFAIL_MSG( wxT("unknown bitmap format") );
+            return 0;
+    }
+}
 
 size_t wxConvertBitmapToDIB(BITMAPINFO *pbi, const wxBitmap& bitmap)
 {
+    wxASSERT_MSG( bitmap.Ok(), wxT("invalid bmp can't be converted to DIB") );
+
     // shouldn't be selected into a DC or GetDIBits() would fail
     wxASSERT_MSG( !bitmap.GetSelectedInto(),
                   wxT("can't copy bitmap selected into wxMemoryDC") );
 
+    // prepare all the info we need
+    BITMAP bm;
     HBITMAP hbmp = (HBITMAP)bitmap.GetHBITMAP();
+    if ( !GetObject(hbmp, sizeof(bm), &bm) )
+    {
+        wxLogLastError("GetObject(bitmap)");
 
-    BITMAPINFO bi;
+        return 0;
+    }
 
-    // first get the info
+    // calculate the number of bits per pixel and the number of items in
+    // bmiColors array (whose meaning depends on the bitmap format)
+    WORD biBits = bm.bmPlanes * bm.bmBitsPixel;
+    WORD biColors = wxGetNumOfBitmapColors(biBits);
+
+    BITMAPINFO bi2;
+
+    bool wantSizeOnly = pbi == NULL;
+    if ( wantSizeOnly )
+        pbi = &bi2;
+
+    // just for convenience
+    BITMAPINFOHEADER& bi = pbi->bmiHeader;
+
+    bi.biSize = sizeof(BITMAPINFOHEADER);
+    bi.biWidth = bm.bmWidth;
+    bi.biHeight = bm.bmHeight;
+    bi.biPlanes = 1;
+    bi.biBitCount = biBits;
+    bi.biCompression = BI_RGB;
+    bi.biSizeImage = 0;
+    bi.biXPelsPerMeter = 0;
+    bi.biYPelsPerMeter = 0;
+    bi.biClrUsed = 0;
+    bi.biClrImportant = 0;
+
+    // memory we need for BITMAPINFO only
+    DWORD dwLen = bi.biSize + biColors * sizeof(RGBQUAD);
+
+    // first get the image size
     ScreenHDC hdc;
-    if ( !GetDIBits(hdc, hbmp, 0, 0, NULL, pbi ? pbi : &bi, DIB_RGB_COLORS) )
+    if ( !GetDIBits(hdc, hbmp, 0, bi.biHeight, NULL, pbi, DIB_RGB_COLORS) )
     {
         wxLogLastError("GetDIBits(NULL)");
 
         return 0;
     }
 
-    if ( !pbi )
+    if ( wantSizeOnly )
     {
-        // we were only asked for size needed for the buffer, not to actually
-        // copy the data
-        return sizeof(BITMAPINFO) + bi.bmiHeader.biSizeImage;
+        // size of the header + size of the image
+        return dwLen + bi.biSizeImage;
     }
 
     // and now copy the bits
-    if ( !GetDIBits(hdc, hbmp, 0, pbi->bmiHeader.biHeight, pbi + 1,
-                    pbi, DIB_RGB_COLORS) )
+    void *image = (char *)pbi + dwLen;
+    if ( !GetDIBits(hdc, hbmp, 0, bi.biHeight, image, pbi, DIB_RGB_COLORS) )
     {
         wxLogLastError("GetDIBits");
 
         return 0;
     }
 
-    return sizeof(BITMAPINFO) + pbi->bmiHeader.biSizeImage;
+    return dwLen + bi.biSizeImage;
 }
 
-#ifdef __VISUALC__
-    #pragma warning(default:4701)
-#endif // __VISUALC__
-
 wxBitmap wxConvertDIBToBitmap(const BITMAPINFO *pbmi)
 {
     // here we get BITMAPINFO struct followed by the actual bitmap bits and
     // BITMAPINFO starts with BITMAPINFOHEADER followed by colour info
     const BITMAPINFOHEADER *pbmih = &pbmi->bmiHeader;
 
+    // offset of image from the beginning of the header
+    DWORD ofs = wxGetNumOfBitmapColors(pbmih->biBitCount) * sizeof(RGBQUAD);
+    void *image = (char *)pbmih + sizeof(BITMAPINFOHEADER) + ofs;
+
     ScreenHDC hdc;
     HBITMAP hbmp = CreateDIBitmap(hdc, pbmih, CBM_INIT,
-                                  pbmi + 1, pbmi, DIB_RGB_COLORS);
+                                  image, pbmi, DIB_RGB_COLORS);
     if ( !hbmp )
     {
         wxLogLastError("CreateDIBitmap");