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Hi

I am trying to load a .png value as wallpaper to my application.
However it is giving me following error
CExtBitmapCache::AlphaBlend’ : function does not take 3 arguments
I tried using 6 different formats of AlphaBlend still facing the same problem
Could you rectify the below code and suggest some solution


CExtSkinBitmap pBitmap;
LPCTSTR strPngImageResourceID;
LPCTSTR strPngResourceSection;
HRSRC hRsrc;
CRect rectInside;
GetClientRect(rectInside);
strPngImageResourceID = MAKEINTRESOURCE(IDB_SPLASHR2);
strPngResourceSection = _T("PNG");
hRsrc = ::FindResource(AfxGetInstanceHandle(), strPngImageResourceID, strPngResourceSection );
ASSERT(hRsrc);
VERIFY(pBitmap.LoadPNG_Resource(AfxGetInstanceHandle(),hRsrc));
HDC hDc= ::GetDC(AfxGetMainWnd()->m_hWnd);
pBitmap.AlphaBlend(hDc,&rectInside,255);

The problem seems to be that the format you’d like to use is not declared as virtual function in CExtBitmap class. I used the following class to make it compile successfully:

class CMySkinBitmap : public CExtSkinBitmap
{
public:
	virtual int AlphaBlend(
		HDC hDC,
		const RECT & rcDst,
		BYTE nSCA = 0xFF) const
	{
		return CExtBitmap::AlphaBlend(hDC, rcDst, nSCA);
	}
};

And then use this class instead of CExtSkinBitmap. I hope it will work, I didn’t test it running.

It seems you would like to use the following format of AlphaBlend: int AlphaBlend(HDC hDC, const RECT & rcDst, BYTE nSCA = 0xFF) const; In this format, the second parameter is a rect given as a reference-parameter, but not as a pointer. In your call pBitmap.AlphaBlend(hDc,&rectInside,255); the second parameter is a pointer to a rect. So try calling pBitmap.AlphaBlend(hDc,rectInside,255); , which could be really pBitmap.AlphaBlend(hDc,rectInside); as the third parameter’s default value is the same (0xFF = 255).