Thread: Super-Newbie. Need to see how to use LoadBitmap() correctly?

Hi, I am trying to load a bitmap as the background of my first windows app. So I tried using LoadBitmap() but I am using it wrong. I set the first parameter to "hwnd", and the second I set to the name of a pointer that contains the text: "C://a_bitmap.bmp". But this is not the type of pointer it wants. But the documentation specifically states:
_________________________________________


HBITMAP LoadBitmap(

HINSTANCE hInstance, // handle of application instance
LPCTSTR lpBitmapName // address of bitmap resource name
);
Parameters

hInstance

Identifies the instance of the module whose executable file contains the bitmap to be loaded.

lpBitmapName

Points to a null-terminated string that contains the name of the bitmap resource to be loaded.

________________________________________

Can someone help?

Well for a start hInstance is a peramiter passed to WinMain. Dont use the handle to a window (hwnd).

Second, if your using VC++, load the bitmap as a resource. Go to its properties and put inverted commas before and after its name (IE "MyBitmap" not MyBitmap)

Then do

char BM1[] = "MyBitmap";

LoadBitmap(hInstance,BM1);

I had loads of problems once with this function. This is the method I use and it should work.

Thanks, I will first change the "hwnd" to "hinstance" and see if it works. I don't have the Visual C++ compiler, I am using Bloodsheds Dev C++ compiler. Can't I keep the second parameter as a filepath(well a pointer to the text "C://myBitmap.bmp" ? If not then what?

I always use rc files.

Try creating a file with

Code:

MyBitmap BITMAP  "C:\MyBitmap.bmp"

and save it as yourproject.rc

now add that to the project when you compile (I have never used Bloodshed so I dont know how this is exactly done on that compiler).

You should then be able to use

Code:

char BM1[] = "MyBitmap"; 

LoadBitmap(hInstance,BM1);

Anyway - give it a go see if it works

Thank you. But shouldn't it be:

BITMAP MyBitmap "C:\MyBitmap.bmp"

...instead of:

MyBitmap BITMAP "C:\MyBitmap.bmp"

??



Either way, I will try it!! Thanks!!

Ok, here's what I did:

The program already generated a .rc file for the icon, I think, and so I just added that snippet to it, saved it, changed the "hwnd" to "hThisInstance"(that's my hinstance) in my program, and set the second parameter to "myBitmap". But not only does the compiler say that "myBitmap" is undeclared, but also "hThisInstance"!! I rechecked my code, and it should recognize "hThisInstance" at least. Now here's what the resource file looks like:
____________________________________
500 ICON MOVEABLE PURE LOADONCALL DISCARDABLE "C:/DEV-C++/Icon/MAINICON.ICO"

myBitmap BITMAP "C//:nuntitled.bmp"

_____________________________________

I also tried it the other way around, that is:

BITMAP myBitmap "C//:nuntitled.bmp"

...didn't work either.

Now, could it be that I should give it more "commands" as the icon also defined there was (the: ...MOVEABLE PURE LOADONCALL DISCARDABLE ...part?)

I just don't know.

As of now, all my app consists of is the window, it's title, a gray background, an ellipse, and text over that ellipse! At this rate, I should have a nice application written in Win95 by the release of Windows 2020!

Originally posted by Sebastiani
Ok, here's what I did:

The program already generated a .rc file for the icon, I think, and so I just added that snippet to it, saved it, changed the "hwnd" to "hThisInstance"(that's my hinstance) in my program, and set the second parameter to "myBitmap". But not only does the compiler say that "myBitmap" is undeclared, but also "hThisInstance"!! I rechecked my code, and it should recognize "hThisInstance" at least. Now here's what the resource file looks like:
____________________________________
500 ICON MOVEABLE PURE LOADONCALL DISCARDABLE "C:/DEV-C++/Icon/MAINICON.ICO"

myBitmap BITMAP "C//:nuntitled.bmp"

_____________________________________

I also tried it the other way around, that is:

BITMAP myBitmap "C//:nuntitled.bmp"

...didn't work either.

I also use Dev-C++ and this is the correct way to do it.

In the resource file include the bitmap like this

PHP Code:

myBitmap BITMAP "C:/nuntitled.bmp" 


In the source code declare a general variable for the bitmap.

PHP Code:

HBITMAP hBmp; 


You can do it also for HINSTANCE but I prefer to get it from hWnd.

In the windows procedure include the following

PHP Code:

....
case WM_CREATE:
        {
         HINSTANCE hInst = GetWindowLong(hWnd, GWL_HINSTANCE);
         hBmp = LoadBitmap(hInst, "myBitmap");
        }
break;

....

case WM_PAINT:
        /* Include here the functions to paint 
            the bitmap in the client area */
break;

.....

case WM_DESTROY:
        DeleteObject(hBmp);
break;

.... 


hth

Thank you, sir. I will try it right away!

Focusing on this bit of code:

////////////////////////////////////////////////////////

case WM_CREATE:
{
HINSTANCE hInst = GetWindowLong(hWnd, GWL_HINSTANCE);
hBmp = LoadBitmap(hInst, "myBitmap");
}
break;

//////////////////////////////////////////////////////////////

...there was an error. So I separated each sub-statement like so:

GetWindowLong(hWnd,

GWL_HINSTANCE); //line 105

...and there was definately an error at 105, though I looked it up and it looks correct.

I even tried other GWL_'s and still the error.

In every case, the compilers complaint was the same:

"attempt to make pointer from integer without a cast..."

Any ideas?