C / C++ / MFC

transoft27-Oct-10 17:19

transoft

27-Oct-10 17:19

You can run two Modeless Dialog Boxes.

following might help you.

http://msdn.microsoft.com/en-us/library/ms644996%28VS.85%29.aspx[^]

Luc Pattyn27-Oct-10 17:24

Luc Pattyn

27-Oct-10 17:24

A dialog, i.e. a window shown as modal, by definition is unique within a process, as it grabs you, your mouse and keyboard until you dismiss it.

If you want two dialogs, you need two processes.

Or you switch to modeless windows, which aren't dialogs at all. But then other forms of the same process could also be brought to the foreground and operated on.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Stephen Hewitt27-Oct-10 18:47

Stephen Hewitt

27-Oct-10 18:47

Luc Pattyn wrote:
If you want two dialogs, you need two processes.

This isn't true. It's possible and quite common for a modal dialog to have a button (or some other mechanism) which brings up another "nested" (not nested in a parent-child sense) modal dialog. Both dialogs are modal and shown at the same time although while the nested one exists the parent one is disabled.

Steve

Re: how to simultaneously show 2 dialogs [modified]

Luc Pattyn28-Oct-10 1:35

Luc Pattyn

28-Oct-10 1:35

You're right of course, however that still leaves only one accessible dialog, not what the OP wants.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Xie Jinghui27-Oct-10 21:11

Xie Jinghui

27-Oct-10 21:11

define dlg2 as a member varibale of CDlg1.

CDlg2 * m_pDlg2;

BOOL CDlg1::OnInitDialog()
{
    // ...
    m_pDlg2 = new CDlg2();
    m_pDlg2->Create(IDD_DIALOG2, this);
    m_pDlg2->ShowWindow(SW_SHOW);
    // ...
}

void CDlg1::OnDestroy()
{
    CDialog::OnDestroy();

    // TODO: Add your message handler code here
    if(m_pDlg2)
        delete m_pDlg2;
    m_pDlg2 = NULL;
}

modified on Thursday, October 28, 2010 4:17 AM

Stephen Hewitt28-Oct-10 0:32

Stephen Hewitt

28-Oct-10 0:32

Why bother using new and delete and the pointer m_pDlg2? In general I'd lose the new and delete (and in this case the OnDestroy handler too) and embed CDlg2 directly:

class CDlg1 : /* Stuff removed */
{
// ... Stuff removed ...
   CDlg2 m_Dlg2;
// ... Stuff removed ...
};
 
BOOL CDlg1::OnShowOtherDialog()
{
   // ...
   m_Dlg2.Create(IDD_DIALOG2, this);
   m_Dlg2.ShowWindow(SW_SHOW);
   // ...
}

Steve

Xie Jinghui28-Oct-10 15:47

Xie Jinghui

28-Oct-10 15:47

Good advice,
en,, I prefer to use pointer..

Stephen Hewitt29-Oct-10 23:57

Stephen Hewitt

29-Oct-10 23:57

I prefer to avoid using the heap when it's not necessary: It's faster, safer and helps minimise heap fragmentation.

Steve

Ratio color bar for an MFC-based application

federico.strati28-Oct-10 2:57

federico.strati

28-Oct-10 2:57

If you don't need 2 dialogs at the same time but you need
them both displayable, then you're speaking about something like
a tabbed dialog: each tab will show a dialog.
I've a sample of doing this at the demo app that is in the article A Standard Multithreaded Dynamic Queue.

Otherwise you want to investigate modeless dialogs.

marc ochsenmeier27-Oct-10 9:42

27-Oct-10 9:42

Hi,

for those who know 'WinRar', when you select a file which has been compressed and right click and select Properties > Archive, you get a nice column showing the compression Ratio in %.

Can someone provide a URL to a sample that implements such a type of column bar? I need such column bar for a Ratio representation in an MFC-based app (aka. C++ based-app, NO .NET).

Thanks in advance for any hint.

Marc

Code-o-mat27-Oct-10 11:31

27-Oct-10 11:31

I don't have WinRar installed but just an idea: use Spy++ to find out the class of that control and then try googling it up, maybe it turn up something usefull...

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Leela: Fry, you're wasting your life sitting in front of that TV. You need to get out and see the real world.
Fry: But this is HDTV. It's got better resolution than the real world <

«_Superman_»27-Oct-10 12:16

«_Superman_»

27-Oct-10 12:16

It shows in the property window of compressed files.
So it must be a shell extension.
You may not be able to get to pick only the control out with spy.
It may not even be a control.
It could be simply drawn.
You never know.

«_Superman_»

I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

Polymorphism in C

marc ochsenmeier27-Oct-10 19:39

27-Oct-10 19:39

I fear, you are wright!

marc ochsenmeier27-Oct-10 20:10

27-Oct-10 20:10

Found this:
Enhanced Progress Bar Control[^]

This is the kind of Drawing I needed. Thanks

Code-o-mat27-Oct-10 21:52

Re: Ratio color bar for an MFC-based application [modified]

27-Oct-10 21:52

«_Superman_» wrote:
You never know.

...unless you try. Was just an idea, maybe it works, maybe it does not.

marc ochsenmeier27-Oct-10 19:38

27-Oct-10 19:38

very good idea. Thanks. I have tried with Spy++ and it is NOT an OCX control, it is pure drawing functions. This IS the kind of Drawing functions I am looking for!

modified on Thursday, October 28, 2010 1:44 AM

CImage and transparency

Craig Longman27-Oct-10 7:39

Craig Longman

27-Oct-10 7:39

I have a button that I want an image in, a basic colour swatch. I liked the idea of having a partially transparent shadow around it, so in GIMP, I created a 32 bit BMP with the desired alpha shadow, and a white, totally non-transparent square in the middle. The intention was to fill the white area in with the colour that the user chooses. Sounds simple enough. So, the basic code is such:

HDC hDC;
HANDLE hOldBmp;
HBRUSH hBrush;
LOGBRUSH zLogBrush;

HBITMAP hColourShadowBmp_ = ::LoadBitmap( hInst, MAKEINTRESOURCE(IDB_COLOUR_SHADOW) );

zLogBrush.lbStyle = BS_SOLID;
zLogBrush.lbColor = RGB( m_Props.uiRed, m_Props.uiGreen, m_Props.uiBlue );
zLogBrush.lbHatch = NULL;

hBrush = ::CreateBrushIndirect( &zLogBrush );

CImage zFinalImage;
CImage zSwatchImage;

zFinalImage.Attach( hColourShadowBmp_ );
zSwatchImage.Create( 20, 20, 24 );

hDC = zSwatchImage.GetDC();
::SelectObject( hDC, hBrush );
::Rectangle( hDC, 0, 0, 20, 20 );
zSwatchImage.ReleaseDC();

hDC = zFinalImage.GetDC();
zSwatchImage.AlphaBlend( hDC, 2, 2, 255 );
zFinalImage.ReleaseDC();

hOldBmp = (HANDLE)
    ::SendMessage( ::GetDlgItem( m_hWnd, IDC_COLOUR ),
                   BM_SETIMAGE,
                   (WPARAM)IMAGE_BITMAP,
                   (LPARAM)zFinalImage.Detach() );

::DeleteObject( hBrush );

All I end up with is the source shadow image, with a lovely fully transparent square where the swatch should be. I know the swatch painting is working, as I can send that image and get the colour square I expect.

Yet nothing I do seems to be able to make the colours get transferred. Crazily enough, the alpha is, if I set the alpha in the AlphaBlend() call to 0, I get the original shadow image unchanged. So I know that it is modifying the alpha channel properly at least. The source is opaque, so no amount of pre-multiplying will help.

FWIW, I also tried making the zSwatchImage a 32 bit with alpha, but it made no difference.

The only solution I can see now is jumping into the bits for the shadow image and changing the RGB values to what I want.

But surely I'm doing something wrong? It's hard to believe that a simply blend like this fails.

Thanks,

CraigL

Code-o-mat27-Oct-10 7:47

27-Oct-10 7:47

Don't be surprised, GDI drawing methods zero out the aplha channel. When you call Rectangle it "makes a hole" in your alpha channel. Use GDI+ or fill the pixels by writing memory directly.

Craig Longman27-Oct-10 8:13

Craig Longman

27-Oct-10 8:13

I can see that being a problem if I had an alpha channel in the zSwatchImage. And at one point I did, so I guess I'd expect the behaviour I saw.

But it's absurd to me that an "alpha blend" function can't take a 24bit image and "do the right thing" by copying it will the alpha channel opaque. Especially when you TELL it what the alpha value to copy with should be. If it isn't there, you'd think it would use the alpha provided as the source alpha, not just the blend alpha. But to take a 24bit image and assume the alpha is zero?

And, I had thought that CImage did use GDI+, so the 24 -> 32 bpp copy would make sense.

I guess I just expect too much from CImage.

Course, now I'm having fun trying to get the bits directly from a BMP loaded via ::LoadBitmap... I guess graphics never really was a win32 strong point.

Thanks for the reply. Normally, I totally exclude win32 APIs wrt image handling, just needed the BMP to use the easy way one can put it on a button. This exercise has just cinched that opinion even more =)

Craig Longman27-Oct-10 8:27

Craig Longman

27-Oct-10 8:27

OK, I stumbled upon the ::LoadImage() after thinking there must be a function more up-to-date that ::LoadBitmap(), and it lets me load a DIB from a resource, and then ::GetObject() gives me the bits.

Thanks,

CraigL

Code-o-mat27-Oct-10 8:52

27-Oct-10 8:52

Cool

Alain Rist27-Oct-10 8:30

Alain Rist

27-Oct-10 8:30

Hi Craig,

Craig Longman wrote:
Course, now I'm having fun trying to get the bits directly from a BMP loaded via ::LoadBitmap

From LoadBitmap[^] LoadBitmap creates a compatible bitmap of the display.

Use LoadImage()[^] with LR_CREATEDIBSECTION to use the xxxBlend GDI functions.
As was already answered GDI+ (not MFC CImage which uses it only for file exchanges) handles that correctly.
cheers,
AR

When the wise (person) points at the moon the fool looks at the finger (Chinese proverb)

transoft27-Oct-10 17:23

transoft

27-Oct-10 17:23

FYI:

GDI+ is not working properly under windows 7.