bitmap not going onto screen

i just did up a bitmap (.bmp) in mspaint so i can display on my main window when the program starts up. i first put the bitmap as a resource and then loaded it. in the code i load the bitmap and work with a device context and a memdc so i can display the bitmap on the client area. but when i run the program, the bitmap does not show up on the window like i thought i coded it to.

here's my resource file with the bitmap in it:

Code:

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#include <windows.h>
#include "resources.h"

500 ICON MOVEABLE PURE LOADONCALL DISCARDABLE "C:/Dev-C++/Icon/MAINICON.ICO"

MainBMP BITMAP "C:/Progs/WinAPI/WinQuiz/WinQuiz.bmp"

OptDlg DIALOG 5, 5, 150, 100
STYLE DS_MODALFRAME | WS_VISIBLE | WS_SYSMENU | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | DS_MODALFRAME
CAPTION "Quizer Options/Settings"
{
 DEFPUSHBUTTON "Continue...", IDD_OKAY, 32, 50, 30, 14, WS_CHILD | WS_VISIBLE | WS_TABSTOP
 PUSHBUTTON "Exit", IDB_EXIT, 32, 50, 30, 14, WS_CHILD | WS_VISIBLE | WS_TABSTOP
 EDITTEXT IDE_EFILE, 5, 5, 25, 10, ES_LEFT | ES_AUTOHSCROLL | WS_CHILD | WS_VISIBLE | WS_BORDER | WS_TABSTOP
 GROUPBOX "File Chooser", IDF_FFRAME, 1, 1, 40, 20
 PUSHBUTTON "Browse...", IDB_BROWSE, 1, 1, 40, 20, WS_CHILD | WS_VISIBLE | WS_TABSTOP
 CTEXT "Recent Files:", IDS_RECLAB, 1, 1, 40, 20, WS_CHILD | WS_VISIBLE
 LISTBOX IDL_RECENT, 1, 1, 40, 20, WS_CHILD | LBS_NOTIFY | WS_VISIBLE | WS_BORDER | WS_VSCROLL |WS_TABSTOP
 PUSHBUTTON "Add/Remove", IDB_ADDREM, 1, 1, 40, 20, WS_CHILD | WS_VISIBLE | WS_TABSTOP
}

---

and here's the snippet of code that i use to load and display the bitmap:

Code:

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/* get a handle to the bitmap */
            hMainBMP = LoadBitmap(hInst, "MainBMP");

            if(hMainBMP == NULL)
                MessageBox(NULL, TEXT("Couldn't display bitmap!"), TEXT("Error!"), 0);

            /* display the bitmap on the window */
            hDC = GetDC(hwnd);
            memDC = CreateCompatibleDC(hDC);
            SelectObject(memDC, hMainBMP);
            BitBlt(hDC, 0, 0, 363, 222, memDC, 0, 0, SRCCOPY);
            ReleaseDC(hwnd, hDC);
            DeleteDC(memDC);

---

what could i possibly be doing wrong so that the bitmap is not being displayed on the window like i'm expecting it to?

thanks!

I had this problem once. Try making the handle to the bitmap a static variable.

Instead of this......

Code:

---

/* get a handle to the bitmap */
            hMainBMP = LoadBitmap(hInst, "MainBMP");

            if(hMainBMP == NULL)
                MessageBox(NULL, TEXT("Couldn't display bitmap!"), TEXT("Error!"), 0);

            /* display the bitmap on the window */
            hDC = GetDC(hwnd);
            memDC = CreateCompatibleDC(hDC);
            SelectObject(memDC, hMainBMP);
            BitBlt(hDC, 0, 0, 363, 222, memDC, 0, 0, SRCCOPY);
            ReleaseDC(hwnd, hDC);
            DeleteDC(memDC);

---

Try this.....

Code:

---

/* get a handle to the bitmap */
            hMainBMP = LoadBitmap(hInst, "MainBMP");
            HBITMAP OldBitmap;

            if(hMainBMP == NULL)
                MessageBox(NULL, "Couldn't display bitmap!", "Error!"), MB_OK | MB_ICONERROR);

            /* display the bitmap on the window */
            hDC = GetDC(hwnd);
            memDC = CreateCompatibleDC(hDC);
            // Draws Bitmap
            OldBitmap= (HBITMAP)SelectObject(memDC, hMainBMP);
            BitBlt(hDC, 0, 0, 363, 222, memDC, 0, 0, SRCCOPY);
            SelectObject(memDC, OldBitmap);

            ReleaseDC(hwnd, hDC);
            DeleteDC(memDC);

---

What about your hInstance?is it global ? and how are you retracting it?;

if not global.before loadbitmap do this;
hInstance = (LPCREATESTRUCT) lParam)->hInstance)))

and as minesweeper said, make your handle static.



cheers!

i have fixed the problem but i dont know why i have fixed it and the reasons behind what my other problem was. now the bitmap is correctly place on the screen where i want it. what i had before was i was putting the bitmap on the window in the wm_create message, so i decided that i should probably put it when the window receives the wm_paint message. so i did that and it all worked out. here's the code snipped:

Code:

---

            /* get a handle to the bitmap */
            hMainBMP = LoadBitmap(hInst, TEXT("MainBMP"));

            if(hMainBMP == NULL)
                MessageBox(NULL, TEXT("Couldn't display bitmap!"), TEXT("Error!"), 0);

            /* display the bitmap on the window */
            return 0;

        case WM_PAINT:
            hDC = BeginPaint(hwnd, &ps);

            memDC = CreateCompatibleDC(hDC);
            SelectObject(memDC, hMainBMP);

            BitBlt(hDC, 13, 8, 363, 222, memDC, 0, 0, SRCCOPY);

            DeleteDC(memDC);
            EndPaint(hwnd, &ps);
            return 0;

---

now, i have no idea why the code didnt work while it was in wm_create. maybe because the window had not had its initial drawing and i was trying to put an image on something that didnt exist? but that cant be, because the window, even if not on the screen, should still have a device context, which i was writing to.

any idea why that didnt work then but does work now? thanks.