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Win32 API Noobie - Custom resource not found, error 1812

I'm a beginning Win32 API programmer trying to get to grips with some of Petzold's examples.

The example here is the PoePoem program that illustrates use of Custom Resources.  The custom resource is an external text file, PoePoem.txt, in ASCII.

The .RC Script has the following entry...

    ////////////////////////
    //
    // TEXT
    //
    ANNABELLEE TEXT DISCARDABLE "PoePoem.txt"

The RESOURCE.H header file has this entry...

    #define ANNABELLEE 102

When I load the compiled exe into a hex editor I can see the text is included in the file, so I know the resource is 'on board'.

However, when I try to load the resource...

    hResource = LoadResource (hInst, FindResource (hInst, TEXT("ANNABELLEE"),TEXT ("TEXT"))) ;

...I get Error 1812 "The Specified Image File did not contain a resource section".  Having isolated the FindResource statement I am sure that it is returning a null pointer, so it either doesn't like the ANNABELLEE reference, or it doesn't like the custom TEXT reference.

If I try to get cute with it and force it to use 102...

    hResource = LoadResource (hInst, FindResource (hInst, TEXT("#102"),TEXT ("TEXT"))) ;

... I get Error 183, "Cannot create a file when that file already exists", which is odd if I'm trying to get a handle to a resource.

I'm using Visual Studio 6, on Windows 2000.

Your help would be appreciated.
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Hiblet
Asked:
Hiblet
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1 Solution
 
Jaime OlivaresCommented:
I feel your hInst is not correct. Please specify how have you obtained.
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HibletAuthor Commented:
The hInst variable is declared at Global scope, and it *seems* to come back filled from a child scroll bar creation...

         hScroll = CreateWindow (TEXT ("scrollbar"), NULL,
                                  WS_CHILD | WS_VISIBLE | SBS_VERT,
                                  0, 0, 0, 0,
                                  hwnd, (HMENU) 1, hInst, NULL) ;
 
However, when I debug this, I can see hInst has a null value, which probably means this is Win95 code???

I'm thinking that the FindResource call needs the handle to the parent window to get to the resource, and instead it's currently using a handle to the child control that returns null in Win2k.  How do I get the right handle?
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Jaime OlivaresCommented:
FindResource  don't need the parent to a window (HWND). It need a parent to your application (HINSTANCE).

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HibletAuthor Commented:
OK, so I set up a global variable hInst, and set it to the value of hInstance in WinMain.  In this way, it should be in scope, and should hold a value for when I'm in the call back Windows procedure.

Debugging shows that the value is held, to the Callback procedure.  So far so good, I have a valid hInst value now, not null, and it's the value of hInstance from the WinMain routine.

I have also set up an HRSRC hRes variable to hold the resource handle before attempting to loadResource it.

As such I can now get the error from FindResource, even when it has (what I believe to be is a) valid handle to the current instance.  

Now I get error 1814: The specified resource name cannot be found in the image file, which at least is a bit more sensible than previous errors...
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Jaime OlivaresCommented:
try with

hResource = LoadResource (hInst, FindResource (hInst, MAKEINTRESOURCE(102),TEXT ("TEXT"))) ;


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HibletAuthor Commented:
With this, I get Error 183 "Cannot create a file when that file already exists".
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Jaime OlivaresCommented:
Who is the error from? LoadResource or FindResource?
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HibletAuthor Commented:
This is from FindResource, now that I've separated it from the composite LoadResource statement.

*Here, our Noobie programmer figures it out*

I have left the error trap in the path, so no matter what happens, I get an error.  I have just take the error trap out, and the programme now works.

I think the correction occurred when you pointed the finger at hInst, so I couldn't have got it working without this help.  Petzold's code does not set hInst to the hInstance value, so that was where it was going wrong, hInst was NULL, hence the FindResource returned NULL also.

Job done.
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Jaime OlivaresCommented:
Ok, glad to help you. See you on the next Noobie question. ;-)
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