Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Pass Bitmap from VB to VC++

Posted on 2002-04-28
8
Medium Priority
?
352 Views
Last Modified: 2013-12-03
Hi,

I've written an MFC ActiveX control.

I want to be able to pass a bitmap into this control.

What is the 'type' of the property I need to create in order to receive the bitmap ??

I've tried creating an LPDISPATCH property, and put the following...

CBitmap MyBMP;
MyBMP=(CBitmap)m_bitmapfromvb;

But the compiler says that it can't translate from one to the other. )-:

Smg.
0
Comment
Question by:smegghead
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 2
  • 2
8 Comments
 
LVL 10

Author Comment

by:smegghead
ID: 6974878
Sorry, forgot to mention, the bitmap is coming from VB.
0
 
LVL 25

Expert Comment

by:clockwatcher
ID: 6975333
When you say the bitmap is coming from VB, what format is it in VB and how are you trying to pass it?  Is it an array of bytes or is it a COM object supporting IPicture (like a StdPicture or the Image property of an Image Control or a PictureBox) or is it a handle to a bitmap?
0
 
LVL 10

Author Comment

by:smegghead
ID: 6976504
Hi,

Probably either using LoadPicture or LoadResPicture.

But if there's a different way, which makes it easier to pass into VC++ then I'm quite flexible on that.
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 6

Expert Comment

by:DrDelphi
ID: 6977034
I'm fairly sure that you'll have to use IPictureDisp. At least my experience sending bitmap from my Delphi/BCB libaries to VB has always entailed using it.I've no reason to believe that it would be any different going the other way.




Good luck!!
0
 
LVL 10

Author Comment

by:smegghead
ID: 6977262
OK, but do you know what OLE type I should be expecting in the C++ program ?? should I use LPUKNOWN or LPDISPATCH ?? (just a guess)
0
 
LVL 6

Expert Comment

by:DrDelphi
ID: 6977585
LPUNKNOWN. Again, to the best of my knowledge and experience.


Good luck!!
0
 
LVL 25

Accepted Solution

by:
clockwatcher earned 200 total points
ID: 6977896
The following works for me with ATL.  I don't know MFC so probably can't help much with creating a CBitmap from an IPictureDisp.

C++ code--

STDMETHODIMP CTesting::DrawImage(LPDISPATCH image)
{

   IPicture* picture;

   if (SUCCEEDED(image->QueryInterface(IID_IPicture, reinterpret_cast<void**>(&picture))))
   {
      HDC hdc = GetDC(NULL);

      OLE_YSIZE_HIMETRIC height;
      OLE_XSIZE_HIMETRIC width;


      picture->get_Height(&height);
      picture->get_Width(&width);

      picture->Render(hdc, 1, 1, 100, 100, 0, 0, width, height, NULL);
         
      picture->Release();

      ReleaseDC(NULL, hdc);
   }

   return S_OK;
}


VB code --

Sub TESTING()

    Dim myATL As Object
    Dim myPic As StdPicture
   
    Set myATL = CreateObject("VBPIC.TESTING")
    Set myPic = LoadPicture("c:\testing123.bmp")
    myATL.drawimage myPic
   
End Sub
0
 
LVL 10

Author Comment

by:smegghead
ID: 6980010
Hi,

I was being stupid... there is actually a parameter type called LPPICTUREDISP.

This accepts the return value from a LoadPicture, or LoadResPicture in VB.

Once in C++ it is coded as follows...

CPictureHolder MyPic;
MyPic.SetPictureDispatch(InPicture);

Where InPicture is of type LPPICTUREDISP.

So, it's all sorted.

I will give these points to clockwatcher, as he/she gave some other useful advice.

Thanks all
0

Featured Post

Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

When writing generic code, using template meta-programming techniques, it is sometimes useful to know if a type is convertible to another type. A good example of when this might be is if you are writing diagnostic instrumentation for code to generat…
Introduction This article is the first in a series of articles about the C/C++ Visual Studio Express debugger.  It provides a quick start guide in using the debugger. Part 2 focuses on additional topics in breakpoints.  Lastly, Part 3 focuses on th…
The viewer will learn additional member functions of the vector class. Specifically, the capacity and swap member functions will be introduced.
The viewer will learn how to clear a vector as well as how to detect empty vectors in C++.

721 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question