Thread: Error loading custom cursor

When I try to load a custom cursor into my program using this code

Code:

  wndclass.hCursor        = LoadCursor(NULL, IDC_CROSSHAIR);

and it gives me this error

Code:

error: invalid conversion from 'int' to 'const CHAR*'

if it helps any, here is my resource.h file

Code:

//incon range: 1000 - 1999
#define IDI_DUCKHUNT 1000
#define IDI_DUCKHUNT_SM 1001

//Bitmap range: 2000 - 2999
#define IDB_DUCK 2000

//Cursor range: 4000 - 4999
#define IDC_CROSSHAIR 4000

and here is my DuckHunt.rc file (I'm making a bad Duck Hunt clone)

Code:

#include "Resource.h"

//Icon
IDI_DUCKHUNT ICON "Res\\DuckHunt.ico"
IDI_DUCKHUNT_SM ICON "Res\\DuckHunt_sm.ico"

//Bitmap
IDB_DUCK BITMAP "Res\\Duck.bmp"

//Curspr
IDC_CROSSHAIR CURSOR "Res\\CrossHair.cur"

So to get it to work I have to change IDC_CROSSHAIR to a const CHAR?

Thanks, it woked

After finishing, the program, and after I compiled it, it just show the loading arrow, then it uses the normal arrow, what's wrong?

In your resource file name your cursor something like MYCURSOR ... not a number and lose the
whole IDC_CROSSHAIR....

In LoadCursor use the cursor's name

LoadCursor (PgmInstance,"MYCURSOR");


If you have the instance handle set to null it will try to load one of Window's stock cursors and error off without finding it. The instance handle you need is passed into your WindMain at startup...

Originally Posted by Sebastiani

Assuming that the OP has stored the icon in the resource section of the executable, MAKEINTRESOURCE should map the identifier to the icon. Textual cursor names open files.

Ummm... no....

The numeric references most C programmers use in windows resources are simply names.

For example if my .rc file says...

Code:

LANGUAGE LANG_ENGLISH,SUBLANG_ENGLISH_US

AMAINICON ICON "RMBrowse.ico"

I can load the icon with LoadIcon(Instance,"AMAINICON");

The file "RMBrowse.ico" is the disk file and it's included in the resources at compile time.
"AMAINICON" is the internal name of the resource.

As long as the Instance handle is not NULL, windows looks for the string name in the resource for that Instance... When it is NULL it looks in it's own resource DLLs...

Icons, Cursors, Bitmaps, Dialogs and Menus have names, not numbers.
Strings are numbered.

Even if you had...

4101 CURSOR "MyCursor.cur"

You could still load it with LoadCursor(Instance,"4101"); because it's a name not a number.

Look at the prototype for MAKEINTRESOURCE...

#define MAKEINTRESOURCEA(i) (LPSTR)((ULONG_PTR)((WORD)(i)))

It just converts your numeric Identifier to a string...

You weren't aware of it because it's not right. You either have a numeric ID and use MAKEINTRESOURCE (or a string starting with a #) or you have a name and use a string. It's trivially provable that you can't use both, just run the following. If strings and IDs were interchangeable you'd expect the LoadCursors to fail or succeed in union, the fact one fails and one succeeds says they aren't.

Code:

#include <windows.h>
#include <iostream>
int main()
{
    HMODULE hMod = LoadLibraryEx(TEXT("shell32.dll"), NULL, LOAD_LIBRARY_AS_DATAFILE);
    HCURSOR hCur = LoadCursor(hMod, TEXT("1001"));
    if(!hCur)
    {
        DWORD err = GetLastError();
        std::cout << "Failed to load hCur with error " << err << '\n';
    }
    else
    {
        DestroyCursor(hCur);
        std::cout << "Loaded hCur successfully\n";
    }
    HCURSOR hCur2 = LoadCursor(hMod, MAKEINTRESOURCE(1001));
    if(!hCur2)
    {
        DWORD err = GetLastError();
        std::cout << "Failed to load hCur2 with error " << err << '\n';
    }
    else
    {
        DestroyCursor(hCur2);
        std::cout << "Loaded hCur2 successfully\n";
    }
    FreeLibrary(hMod);
}

Originally Posted by adeyblue

You weren't aware of it because it's not right. You either have a numeric ID and use MAKEINTRESOURCE (or a string starting with a #) or you have a name and use a string. It's trivially provable that you can't use both, just run the following. If strings and IDs were interchangeable you'd expect the LoadCursors to fail or succeed in union, the fact one fails and one succeeds says they aren't.

Look at my example again...

I used ... 4101 CURSOR "MyCursor.cur"

If it was #4101 CURSOR "MyCursor.cur"

you would be correct.

I don't believe in all the time I've been programming windows I've ever used MAKEINTRESOURCE. I just give stuff names... it's so much easer.

MAINMENU MENU ... LoadMenu(MyProg, "MAINMENU");

SETTINGS DIALOG... DialogBox(...., "SETTINGS"....);

It's almost too easy