C / C++ / MFC

Using a Toolbar with Property Sheets

19-Sep-08 6:51

FWIW I created a quick MFC SDI app and put PostMessage(WM_CLOSE);
at the end of the OnCreate() function of the main window class.

The app closed cleanly.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

si_6918-Sep-08 6:31

si_69

18-Sep-08 6:31

Hi
I am using some propety pages in wizard mode, on one of my pages i am using a toolbar

The first time you use the wizard it all works fine

if you run the wizard again, the toolbar fails to load correctly

The toolbar appears to be there, but there are no images shown on any of the buttons

I am creating the toolbar in the oninitdialog() of the property page using

if(!m_toolBar2.Create(this) || !m_toolBar2.LoadToolBar(IDR_TOOLBAR2))
AfxMessageBox("Failed");

Can anyone help at all ?

thanks

Simon

Appearance of ActiveX Control at Design-time

hhh18-Sep-08 5:46

hhh

18-Sep-08 5:46

Hi all,

I made an ActiveX Control in VB 6.0 which uses region functions to give the control an irregular look, I mean, not a plain square or rectangle. The control looks as it should when placed on a VB Form at design time. However, when I put the same control on a dialog box in VC++ 6.0, it gets a square shape, though at run time the control appears how it should. Is there a difference in the ways VB and VC initalize the same control at design time? Or is there an issue with using the region functions? Please help. Thanks.

Henry.

public struct in a class

Cengine18-Sep-08 5:38

Cengine

18-Sep-08 5:38

Is it good to have a public struct in a class? If its private, is there any way to use getter to get the struct?

toxcct18-Sep-08 5:52

toxcct

18-Sep-08 5:52

you mean, the definition of the type ? or an instance of such a struct ?

[VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

Cengine18-Sep-08 5:58

Cengine

18-Sep-08 5:58

I meant definition

toxcct18-Sep-08 6:02

toxcct

18-Sep-08 6:02

so that doesn't make sense to have a getter to access a type definition.

a getter would be to retrieve a member of the class, which type could be of a defined struct...

so yes, either define your struct outside, or if inner, do it publically (unless it's for the class internal use only)

[VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

Cengine18-Sep-08 6:06

Cengine

18-Sep-08 6:06

thank you for replying my noob questions, regards.

BitBlt does not work in print preview

Matthew Faithfull18-Sep-08 6:12

Matthew Faithfull

18-Sep-08 6:12

I'm not sure what you're doing but perhaps you want something fun like this Smile | :)

<br />
<br />
class CSomething<br />
{<br />
<br />
public:<br />
<br />
  struct MyInterface<br />
  {<br />
    public:<br />
    int Increment( void );<br />
  };<br />
<br />
  MyInterface* QueryInterface()<br />
  {<br />
    return dynamic_cast<myinterface*>(&aHiddenInstance);<br />
  }<br />
<br />
private:<br />
<br />
  struct stHidden : public CSomething::MyInterface<br />
  {<br />
    int Increment( void )<br />
    {<br />
      iHiddenStructMember++;<br />
    }<br />
<br />
    int iHiddenStructMember;<br />
  };<br />
<br />
  stHidden aHiddenInstance;<br />
};<br />
<br />

Geek points obvously to the first person who points out that this is fairly pointless and double to anyone who can guess which old MS technology I'm playing with today Laugh | :laugh:

"The secret of happiness is freedom, and the secret of freedom, courage."
Thucydides (B.C. 460-400)

theCPkid18-Sep-08 5:29

18-Sep-08 5:29

I am trying to draw something into memory DC and then copy it to screen or printer DC. I get the correct output drawing on screen or when directly taking the print out on printer. BUt while viewing print preview, it does not show any output.

CMyView::OnDraw(CDC* pDC)
{
    CTestDoc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);
    if (!pDoc)
        return;

    CRect rcClient;

    if (pDC->IsPrinting()) 
    {
        rcClient = m_rcPrintRect; //obtained from CPrintInfo
    }
    else
    {
        GetClientRect(&rcClient);
    }    

    CBitmap bmp;
    CDC memDC;
    
    memDC.CreateCompatibleDC(pDC);
    bmp.CreateCompatibleBitmap(pDC, rcClient.Width(), rcClient.Height());
    memDC.SelectObject(&bmp);

    memDC.DrawText(L"Hello", &rcClient, DT_CENTER | DT_VCENTER);
    pDC->BitBlt(0,0,rcClient.Width(), rcClient.Height(), &memDC, 0, 0, SRCCOPY);

    bmp.DeleteObject();
    memDC.DeleteDC();

    return;
}

I suspect something is wrong with creating compatible DC. pDC represents printer dc but the display is on screen. How to remove this problem? Sigh | :sigh:

Mark Salsbery18-Sep-08 5:49

18-Sep-08 5:49

What is the value of rcClient when it fails?

I'm not seeing anything wrong with your DC creation...

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

theCPkid18-Sep-08 5:54

18-Sep-08 5:54

I checked it in debug mode. the program does not fail in print preview. BitBlt also completes successfully. only I do not get any output. I can initialize rcClient to (0,0,0,0) but that does not make a difference.
Thanks.

Mark Salsbery18-Sep-08 5:57

18-Sep-08 5:57

ok....and the answer to my question is? Smile | :)

From the debugger, what is the left/top/right/bottom values of the rect?????

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

theCPkid18-Sep-08 6:03

18-Sep-08 6:03

oh sorry...
in print preview, top=0, bottom=6400, left = 0, right=4900 (size of A4 sheet in pixels @600 dpi)

in print, height= 6300, widht=4800...(because of different margin settings?)

the fruits of your success will be in direct ratio to the honesty and sincerity of your own efforts in keeping your own records, doing your own thinking and, reaching your own conclusions.
..surviving in autumn..in love with spring..

Mark Salsbery18-Sep-08 6:34

Re: BitBlt does not work in print preview [modified]

18-Sep-08 6:34

Arghh I'm drawing a blank here LOL

What happens if you do

pDC->MoveTo(rcClient.left, rcClient.top);
pDC->LineTo(rcClient.right, rcClient.bottom);

Do you get a diagonal line?

Also is the bitmap creation succeeding?

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

theCPkid18-Sep-08 7:01

18-Sep-08 7:01

Yes, I get a diagonal line. In fact. there's no problem with drawing directly on print preview dc. I am using memory dc in my code only to avoid flickering (perhaps it was obvious)

The following code draws properly in print preview... by using DIB. But it's heavily slowing down my system. perhaps, I need to create DIB section in more elegant way. DDB provided by create compatible bitmap perhaps does not work. D'Oh! | :doh:

void CMyView::OnDraw(CDC* pDC)
{
    CTestDoc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);
    if (!pDoc)
        return;

    CRect rcClient;

    if (pDC->IsPrinting()) 
    {
        rcClient = m_rcPrintRect;
    }
    else
    {
        GetClientRect(&rcClient);
    }    

    HBITMAP bmp;
    BYTE* drawingSurfaceBits;
    BITMAPINFOHEADER            BMIH;
    BMIH.biSize = sizeof(BITMAPINFOHEADER);
    BMIH.biBitCount = 24;
    BMIH.biPlanes = 1;
    BMIH.biCompression = BI_RGB;
    BMIH.biWidth = rcClient.Width();
    BMIH.biHeight = rcClient.Height();
    BMIH.biSizeImage = ((((BMIH.biWidth * BMIH.biBitCount) + 31) & ~31) >> 3) * BMIH.biHeight;
    bmp = CreateDIBSection(pDC->GetSafeHdc(), (CONST BITMAPINFO*)&BMIH, DIB_RGB_COLORS, (void**)&drawingSurfaceBits, NULL, 0);
    if((bmp == NULL) || (drawingSurfaceBits == NULL))
    {
        AfxMessageBox(L"Bitmap not created", MB_OK | MB_ICONSTOP);
        return;
    }

    memDC.CreateCompatibleDC(pDC);
    memDC.SelectObject(bmp);

     memDC.DrawText(L"Hello", &rcClient, DT_CENTER | DT_VCENTER);
     pDC->BitBlt(0,0,rcClient.Width(), rcClient.Height(), &memDC, 0, 0, SRCCOPY);

    return;
}

Also, in print preview mode, the quality of picture shown on screen is extremely poor. I am perhaps using only rgb etc. I need to study bitmapinfoheader further.

Thanks for the precious help. Smile | :)

modified on Thursday, September 18, 2008 1:07 PM

Mark Salsbery18-Sep-08 7:25

18-Sep-08 7:25

Creating that big bitmap on every draw is going to be a little slow.
I would only (re)create it when the size changes.

theCPkid wrote:
(CONST BITMAPINFO*)&BMIH

Bad cast!!!!! No bueno! You need to pass a pointer to a BITMAPINFO,
not a pointer to a BITMAPINFOHEADER. The cast just hides the error from
the compiler Smile | :)

Try

BITMAPINFO bmi;
memset(&bmi, 0, sizeof(BITMAPINFO));
bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
bmi.bmiHeader.biWidth = rcClient.Width();
bmi.bmiHeader.biHeight = rcClient.Height();
bmi.bmiHeader.biPlanes = 1;
bmi.bmiHeader.biBitCount = 24;
bmi.bmiHeader.biCompression = BI_RGB;
bmi.bmiHeader.biSizeImage = ((((bmi.bmiHeader.biWidth * bmi.bmiHeader.biBitCount) + 31) & ~31) >> 3) * bmi.bmiHeader.biHeight;
//bmi.bmiHeader.biXPelsPerMeter = 0;
//bmi.bmiHeader.biYPelsPerMeter = 0;
//bmi.bmiHeader.biClrUsed = 0;
//bmi.bmiHeader.biClrImportant = 0;

bmp = ::CreateDIBSection(NULL, &bmi, DIB_RGB_COLORS, (void**)&drawingSurfaceBits, NULL, 0);

I'm not sure what's going on with the rendering quality....I'll ponder that
and let you know if I think of something...(maybe the code fix above will do better?)

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

theCPkid18-Sep-08 22:44

18-Sep-08 22:44

Does not make any difference on rendering quality and the quality is very poor. So, I am not using it in my code as of now.
Thanks.

Mark Salsbery19-Sep-08 5:17

19-Sep-08 5:17

It's not your code or my code causing poor quality...either way
should work.

Rendering some text in a 6400x4900 offscreen buffer then squishing it down to fit
a window is going to look bad.

The only way to make it look 100% correct is to make your bitmap the exact
size it will be rendered on the screen.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

theCPkid19-Sep-08 19:49

19-Sep-08 19:49

oh! I got your point. I did not think about it earlier.
Thanks again.

Roger Allen18-Sep-08 14:37

Roger Allen

18-Sep-08 14:37

The issues you may be seeing could be down to what raster operations are supported by the DC types in question.

If you had been saying it shows in preview and not on the printer I would definately have said this, but you have it reversed which makes me intrigued (and I have even come out of CP semi-retirment to answer OMG | :OMG:

)

The first thing I would say is drop BitBlt altogether. its not guaranteed to be compatible with both display DCs and printer DCs. Your best option would be to switch to StretchDIBits, from memory this is compatible with all DC types.

Another thing that could be causing you problems is that your creating a DC compatible with a preview DC, this means you will have all the world transforms which map from print to preview display probably active on your memory DC. Try creating your comapatible DC directtly from the screen by passing NULL instead of pDC. If that fixes the issues then I would say its down to the preview DC supporting all the world transforms and your in effect drawing of the edge of the comaptible bitmap.

If you vote me down, my score will only get lower

theCPkid18-Sep-08 22:42