Dialog Box: Bitmap gets erased when a screen is dragged over. 1

[MrDwight]

I have a dialog box that contains two bitmaps built into the dialog box user interface. While my application runs, it displays new images over the original ones. Unfortunately, when I drag a another window over the images, the original bitmaps reappear instead of the current ones. I am currently using the ActiveX BitBlt to place the new images onto the screen.

How do I make the new images persist?

Thank you for your help.

 

[Jeffray]

post your code to see where you put your code.

 

[MrDwight]

OK, it's kinda lengthy, but here it is. This version actually has three bitmaps instead of the two I stated earlier, but it exhibits the same problem.

bool CMedicalDlg:rawImages()
{
// *** DIRECTDRAW PRIMARY SURFACE CREATION ***
// Prepare specifics of the surface to be created using ddsd (surface description).
ZeroMemory(&ddsd, sizeof(ddsd)); // Init surface description to zeroes.
ddsd.dwSize = sizeof(ddsd);
ddsd.dwFlags = DDSD_CAPS;
ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE;

// Create the surface on the DD2 object using the desired surface description.
ddrval = Image1DD2->CreateSurface(&ddsd, &Box1Primary, NULL);
if (FAILED(ddrval))
{
MessageBox("DirectDraw Surface Creation Failure!", NULL, MB_OK);
return FALSE;
}

// Create a handle to memory device (memoryDC) that is compatible with the screen.
HDC hdcImageReal, hdcImageImag, hdcImageAbs, hdcSurf;
hdcImageReal = CreateCompatibleDC(NULL);
hdcImageImag = CreateCompatibleDC(NULL);
hdcImageAbs = CreateCompatibleDC(NULL);
if (!hdcImageReal || !hdcImageImag || !hdcImageAbs)
{
MessageBox("Failed to create a memory device for hdcImage!", NULL, MB_OK);
Box1Primary->Release();
Box1Primary=NULL;
DeleteObject(hbm);
return FALSE;
}

// Expand the dimensions of the memoryDC to the bitmap dimensions.
if (CreateCompatibleBitmap(hdcImageReal, n, n) == NULL)
MessageBox("CreateCompatibleBitmap Failed for hdcImageReal!", NULL, MB_OK);
if (CreateCompatibleBitmap(hdcImageImag, n, n) == NULL)
MessageBox("CreateCompatibleBitmap Failed for hdcImageImag!", NULL, MB_OK);
if (CreateCompatibleBitmap(hdcImageAbs, n, n) == NULL)
MessageBox("CreateCompatibleBitmap Failed for hdcImageAbs!", NULL, MB_OK);

// Place the Image matrices into linear arrays with an RGB format.
int i, j, a = 0;
unsigned long TmpVal;

for(j=0; j<n; j++)
for(i=0; i<n; i++)
{
TmpVal = unsigned long(ImageMatrixReal[j]);
LinImageReal[a] = TmpVal + TmpVal * 256 + TmpVal * 65536; //Create RGB format.
TmpVal = unsigned long(ImageMatrixImag[j]);
LinImageImag[a] = TmpVal + TmpVal * 256 + TmpVal * 65536; //Create RGB format.
TmpVal = unsigned long(ImageMatrixAbs[j]);
LinImageAbs[a] = TmpVal + TmpVal * 256 + TmpVal * 65536; //Create RGB format.
a++;
}

// Prepare some variables to create a new DI Bitmap
__declspec(align(32)) BITMAPINFO *pbmi = NULL;
pbmi = new BITMAPINFO;
PBYTE pBitmapBits = NULL;
// Setup the BITMAPINFO structure with the bitmap specs.
pbmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
pbmi->bmiHeader.biWidth = n;
pbmi->bmiHeader.biHeight = -n;
pbmi->bmiHeader.biPlanes = 1;
pbmi->bmiHeader.biBitCount = 32;
pbmi->bmiHeader.biCompression = BI_RGB;
pbmi->bmiHeader.biSizeImage = n*n*4;

DeleteObject(hbm);
DeleteObject(hbm2);
DeleteObject(hbm3);

// Create new DI Bitmaps and stuff the image data into them.
hbm = CreateDIBSection(NULL, pbmi, DIB_RGB_COLORS, (PVOID*)pBitmapBits, NULL, 0);
if (hbm == NULL)
MessageBox(&quot;Failed to Create a new DI Bitmap for Real Image!&quot;, NULL, MB_OK);
SetDIBits(hdcImageReal, hbm, 0, n, &LinImageReal[0], pbmi, DIB_RGB_COLORS);

hbm2 = CreateDIBSection(NULL, pbmi, DIB_RGB_COLORS, (PVOID*)pBitmapBits, NULL, 0);
if (hbm2 == NULL)
MessageBox(&quot;Failed to Create a new DI Bitmap for Imaginary!&quot;, NULL, MB_OK);
SetDIBits(hdcImageImag, hbm2, 0, n, &LinImageImag[0], pbmi, DIB_RGB_COLORS);

hbm3 = CreateDIBSection(NULL, pbmi, DIB_RGB_COLORS, (PVOID*)pBitmapBits, NULL, 0);
if (hbm3 == NULL)
MessageBox(&quot;Failed to Create a new DI Bitmap for Absolute Image!&quot;, NULL, MB_OK);
SetDIBits(hdcImageAbs, hbm3, 0, n, &LinImageAbs[0], pbmi, DIB_RGB_COLORS);

// Select the new bitmaps into the memory DC's.
SelectObject(hdcImageReal, hbm);
SelectObject(hdcImageImag, hbm2);
SelectObject(hdcImageAbs, hbm3);

// Determine the Window Locations
CWnd *cPic;
CRect cRealPicRect, cImagPicRect, cAbsPicRect;
CDialog::SetForegroundWindow();
cPic = CDialog::GetDlgItem(Pic_Real);
cPic->GetWindowRect(cRealPicRect);
cPic = CDialog::GetDlgItem(Pic_Imag);
cPic->GetWindowRect(cImagPicRect);
cPic = CDialog::GetDlgItem(Pic_Abs);
cPic->GetWindowRect(cAbsPicRect);
// Adjust for Window borders
cRealPicRect.left += 5;
cImagPicRect.left += 5;
cAbsPicRect.left += 5;
cRealPicRect.top += 5;
cImagPicRect.top += 5;
cAbsPicRect.top += 5;

Box1Primary->GetSurfaceDesc(&ddsd);
if (Box1Primary->GetDC(&hdcSurf) == DD_OK)
{
BitBlt(hdcSurf, cRealPicRect.left, cRealPicRect.top, n, n, hdcImageReal, 0, 0, SRCCOPY);
BitBlt(hdcSurf, cImagPicRect.left, cImagPicRect.top, n, n, hdcImageImag, 0, 0, SRCCOPY);
BitBlt(hdcSurf, cAbsPicRect.left, cAbsPicRect.top, n, n, hdcImageAbs, 0, 0, SRCCOPY);
Box1Primary->ReleaseDC(hdcSurf);
}
else
MessageBox(&quot;Blitter Failure!&quot;, NULL, MB_OK);

FirstTime = FALSE;
Box1Primary->Release();
Box1Primary=NULL;
DeleteObject(hbm);
DeleteObject(hbm2);
DeleteObject(hbm3);
return TRUE;
}

 

[danielprovin]

u just have to handle the WM_PAINT messages, give a look at that:

http://www.flipcode.com/articles/article_win32skins.shtml

then just look at the skinning part, and u can download the code too

and there is one example from the MSDN library at:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/pantdraw_4z6p.asp