Solved

->((CMainFrame*): syntax error : '(' ; why?

Posted on 1998-01-14
4
345 Views
Last Modified: 2010-04-10
I have some errors that I cannot resolve. I'm using VC++ 4.0, DirectX 3.0.

This line:

AfxGetApp()->m_pMainWnd->m_pDirectDraw->GetDisplayMode(&ddsdDesc);

Gives the following error:

Compiling...
MainFrm.cpp
C:\Vc++\Projects\Asteroid\MainFrm.cpp(579) : error C2039: 'm_pDirectDraw' : is not a member of 'CWnd'

m_pDirectDraw, true enough, is not a member of CWnd. It's a member of class CMainFrame (: public CFrameWnd). That's why I need to cast it to CMainFrame, right? So, I tried:

AfxGetApp()->((CMainFrame*)m_pMainWnd)->m_pDirectDraw->GetDisplayMode(&ddsdDesc);

And received this:

Compiling...
MainFrm.cpp
C:\Vc++\Projects\Asteroid\MainFrm.cpp(579) : error C2059: syntax error : '('

What's wrong with a "(" there? I have to cast it. To cast something, you need to enclose the new type in (), right?

How do I fix this?
0
Comment
Question by:TylerRick
  • 2
4 Comments
 
LVL 22

Expert Comment

by:nietod
ID: 1178315
Try
     (CMainFrame*)(AfxGetApp()->m_pMainWnd)->m_pDirectDraw->GetDisplayMode
0
 
LVL 15

Accepted Solution

by:
Tommy Hui earned 50 total points
ID: 1178316
More correctly, you should use MFC's runtime type info:

  CMainFrame* frame = NULL;
  if (AfxGetApp()->m_pMainWnd->IsKindOf(RUNTIME_CLASS(CMainFrame)))
  {
    frame = (CMainFrame*)AfxGetApp()->m_pMainWnd;
    frame->m_pDirectDraw->GetDisplayMode(&ddsdDesc);
  }
  else
  {
    TRACE("Pointer is not the right type!\r\n");
  }

0
 

Author Comment

by:TylerRick
ID: 1178317
Thanks! Both of your suggestions worked.

To nietod:

I had to change your example to:
((CMainFrame*)(AfxGetApp()->m_pMainWnd))->m_pDirectDraw->GetDisplayMode(&ddsdDesc);
0
 

Author Comment

by:TylerRick
ID: 1178318
Thanks! Both of your suggestions worked.

To nietod:

I had to change your example to:

((CMainFrame*)(AfxGetApp()->m_pMainWnd))->m_pDirectDraw->GetDisplayMode(&ddsdDesc);

before it compiled, though.
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

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

Suggested Solutions

Title # Comments Views Activity
how to understand recursion 12 226
FMX enumerated colours 2 100
Best book to learn C++ 4 79
draw a Christmas tree by using a nested loop? 26 62
Article by: SunnyDark
This article's goal is to present you with an easy to use XML wrapper for C++ and also present some interesting techniques that you might use with MS C++. The reason I built this class is to ease the pain of using XML files with C++, since there is…
Templates For Beginners Or How To Encourage The Compiler To Work For You Introduction This tutorial is targeted at the reader who is, perhaps, familiar with the basics of C++ but would prefer a little slower introduction to the more ad…
The viewer will learn how to clear a vector as well as how to detect empty vectors in C++.
The viewer will be introduced to the technique of using vectors in C++. The video will cover how to define a vector, store values in the vector and retrieve data from the values stored in the vector.

773 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