C / C++ / MFC

12-Jul-01 2:42

But i need picture which is unter the window ?? How can i do it ??

What worked OK in your VB program?

Tomasz Sowinski -- http://www.shooltz.com

Re: Error ...

12-Jul-01 3:16

This is code from program in VB :

Function hDCToPicture(ByVal hDCSrc As Long, ByVal LeftSrc As Long, ByVal TopSrc As Long, ByVal WidthSrc As Long, ByVal HeightSrc As Long) As Picture
Dim hDCMemory As Long, hBmp As Long, hBmpPrev As Long, R As Long
Dim hPal As Long, hPalPrev As Long, RasterCapsScrn As Long, HasPaletteScrn As Long
Dim PaletteSizeScrn As Long, LogPal As LOGPALETTE

'Create a compatible device context
hDCMemory = CreateCompatibleDC(hDCSrc)
'Create a compatible bitmap
hBmp = CreateCompatibleBitmap(hDCSrc, WidthSrc, HeightSrc)
'Select the compatible bitmap into our compatible device context
hBmpPrev = SelectObject(hDCMemory, hBmp)
R = BitBlt(hDCMemory, 0, 0, WidthSrc, HeightSrc, hDCSrc, LeftSrc, TopSrc, vbSrcCopy)
hBmp = SelectObject(hDCMemory, hBmpPrev)

R = DeleteDC(hDCMemory)

Set hDCToPicture = CreateBitmapPicture(hBmp, hPal)
End Function
Private Sub Form_Load()
dsk = GetDesktopWindow()
'Create a picture object from the screen
Screen.TwipsPerPixelX, Screen.Height / Screen.TwipsPerPixelY)
srcdc = GetDC(dsk)
Set Me.Picture = hDCToPicture(srcdc, Left / Screen.TwipsPerPixelX, Top / Screen.TwipsPerPixelY, Width / Screen.TwipsPerPixelX, Height / Screen.TwipsPerPixelY)
End sub

Function CreateBitmapPicture(ByVal hBmp As Long, ByVal hPal As Long) As Picture
Dim R As Long, Pic As PicBmp, IPic As IPicture, IID_IDispatch As GUID

'Fill GUID info
With IID_IDispatch
.Data1 = &H20400
.Data4(0) = &HC0
.Data4(7) = &H46
End With

'Fill picture info
With Pic
.Size = Len(Pic) ' Length of structure
.Type = vbPicTypeBitmap ' Type of Picture (bitmap)
.hBmp = hBmp ' Handle to bitmap
.hPal = hPal ' Handle to palette (may be null)
End With

'Create the picture
R = OleCreatePictureIndirect(Pic, IID_IDispatch, 1, IPic)

'Return the new picture
Set CreateBitmapPicture = IPic
End Function

Re: Error ...

Tomasz Sowinski12-Jul-01 3:31

12-Jul-01 3:31

It seems that you're trying to copy the desktop window to a bitmap first. Next, you want to display a dialog and paint its background using saved image. There's a class encapsulating a memory DC and a bitmap on code project; search for CMemDC.

Tomasz Sowinski -- http://www.shooltz.com

Memory monitoring

Geetha11-Jul-01 22:38

Geetha

11-Jul-01 22:38

I would to monitor the memory usage as given in the taskmanager , i would be more helpful if some one provide the solution .

GG

Re: Memory monitoring

Tomasz Sowinski12-Jul-01 1:25

Using of one object in three dialog ...

12-Jul-01 1:25

Check the GlobalMemoryStatus function.

Tomasz Sowinski -- http://www.shooltz.com

Hadi Rezaee11-Jul-01 22:37

11-Jul-01 22:37

Hi all,
I'm writing program about database,
In my program i have three dialogs, and i have to use of CDaoDatabase object in all dialogs ...
I want to use of only one object for do that,
How can i do that ???
Does i must create global variable ?
I mean, writing CDaoDatabase g_db; in first of my source code, and using of extern CDaoDatabase g_db; in other cpp files ???
Do you have any idea ?
My program is in SDI mode ...

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

Tomasz Sowinski12-Jul-01 1:07

12-Jul-01 1:07

Make your CDaoDatabase an application data member and provide an accessor function in your app class...

class CYourApp : public CWinApp
{
// ...
public:
CDaoDatabase& GetDatabase() { return m_db; }
private:
CDaoDatabase m_db;
// ...
};

... and use AfxGetApp in your dialogs to get access to db:

// ... somewhere in dialog methods
CDaoDatabase &db = static_cast<CYourApp *>(AfxGetApp())->GetDatabase();

Tomasz Sowinski -- http://www.shooltz.com

Hadi Rezaee12-Jul-01 2:15

12-Jul-01 2:15

Hi Tomasz, and thanks for reply ...
Can you explain more about your source codes ...
For example, first, you make private member variable CDaoDatabase m_db; and then you make public member function CDaoDatabase &GetDatabase(){return m_db;} !!!
WHY ???
Why you make GetDatabase() function ? why i shouldn't use of only m_db ?
And please explain to me how can i use of GetDatabase() function ...
Because i'm beginner ...
Thanks again ...

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

Tomasz Sowinski12-Jul-01 2:36

12-Jul-01 2:36

For example, first, you make private member variable CDaoDatabase m_db; and then you make public member function CDaoDatabase &GetDatabase(){return m_db;} !!! WHY ???

This is called encapsulation. The main benefit is that you can rename m_db and you'll have to change the name only in two places Poke tongue | ;-P

Tomasz Sowinski -- http://www.shooltz.com

Hadi Rezaee12-Jul-01 4:18

12-Jul-01 4:18

Hi again,
AfxGetApp() is object of CWinApp class, so can't use of m_db or GetDatabase() in AfxGetApp() !!!

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

Tomasz Sowinski12-Jul-01 4:24

12-Jul-01 4:24

You know what static_cast does, don't you?

Tomasz Sowinski -- http://www.shooltz.com

Stan Shannon12-Jul-01 4:59

Stan Shannon

12-Jul-01 4:59

Actually, Tomasz, I would not mind having an explanation of the advantage of static_cast over the old fashioined ((CMyApp*)AfxGetApp())->WhatEver() in this case. Confused | :confused:

Tomasz Sowinski12-Jul-01 7:00

12-Jul-01 7:00

The only syntactic difference is that static_cast won't compile if CYourApp isn't derived from CWinApp, which is highly unlikely. It's just my personal preference to cast the C++ way.

Tomasz Sowinski -- http://www.shooltz.com

Hadi Rezaee13-Jul-01 18:26

13-Jul-01 18:26

Hi Tomasz,
Thank you for your explain ...
Now, can you write example about using of m_db from AfxGetApp() ?

Because in your example you use of GetDatabase() in AfxGetApp(), now can you write example about using m_db in AfxGetApp() ?

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

C~~MFC6.0~~VS.NETUser12-Jul-01 4:48

C~~MFC6.0~~VS.NETUser

12-Jul-01 4:48

AfxGetApp() (if I rememeber right)is a gobal function in MFC which returns a pointer to your CWinApp derived class so you can use "->GetDatabase()" Any public function in this CWinApp derived class called from dialog(other class also outside this discussion) can be called this way.

Stan Shannon12-Jul-01 5:49

Stan Shannon

12-Jul-01 5:49

In all honesty, I don't feel that exposing your db as a pointer or a reference is the best design. I think it would be far better to simply put the db in the mainframe class (or possible a doc class) and have a means of communicating data back and forth between the db and the UI by some sort of intermediate set of classes.

i.e.:

class CSomeDBData // or a struct if your prefer.
{
//whatever
};

CMainFrmame::OnSomeCommand()
{
CMyDialog MyDlg;
CSomeDBData somedata;

m_db.GetSomeData(&somedata);
MyDlg.EditSomeData(somedata);// or however you like.
if( MyDlg.DoModal() == IDOK )
{
MyDlg.GetSomeEditedData(somedata);// or however you like.
m_db.SetSomeData(&somedata);
}
}

This way, you don't end up with pointers and references to your core objects scattered all over your application. Which, as the application grows, will certainly happen unless you take steps to limit it. If your app is large you should concentrate on keeping data centralized and not globally available to anything that might need to access it or which might store pointers to it. This takes a little extra work, but pays off in the long run.

Hadi Rezaee13-Jul-01 18:19

13-Jul-01 18:19

Hi,
Thank's it was nice help ...

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

Hadi Rezaee14-Jul-01 1:49

14-Jul-01 1:49

Hi again Stan,
Your idea was very good, but i have little problem ...

I can check the return value of DoModal() for checking the hited button ...
But when i click on button in the dialog, dialog will close !!!

Now, i want to use of button in the dialog in CManFrame class without dialog will close ...
How can i do that ?

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie