C / C++ / MFC Discussion Boards

Mike Nordell26-Dec-02 6:24

26-Dec-02 6:24

It seems you don't really understand what a DC is. You can't draw lines in a DC, you can draw lines on a bitmap using a DC.

The DC is (among other things) more of a descriptor and abstraction layer of the target device and area.

If you however are sure no one else is selecting a new bitmap into the DC, you could possibly create two DIB sections, select one into the DC, select the other into a compatible DC, and blit the original bitmap into the second one. When you then want to check if anything has changed you can just memcmp the two memory areas.

It would probably be quite slow (I'd expect something like >5 milliseconds for just 640x480x24, even on a moderately fast machine), but short of alternatives it would at least work (maybe you'll have to use 32-bpp to not be bitten by DWORD-alignment and unspecified values at end of every line).

Re: DC (Device Context) Quiestion !

HellShrimp4free26-Dec-02 8:02

HellShrimp4free

26-Dec-02 8:02

oh Jesus.

thanks for your Very Very Great and Compelete Answer Rose | [Rose]

i read your previus answer about Flicker. it was wonderfulllll
thank for your helppp.
-=Ehsan-de-Burge=-

Re: DC (Device Context) Quiestion !

Paul M Watt26-Dec-02 11:55

Paul M Watt

26-Dec-02 11:55

If you are using Memory Device contexts (where you select your own bitmap into the DC) then you can use this function to find the bounding box to the last changes since you ask for the changes:

::GetBoundsRect

However, if you are trying to detect changes on a window, then you will have to resort to other methods.

Build a man a fire, and he will be warm for a day
Light a man on fire, and he will be warm for the rest of his life!

Merging Menus in MFC and OLE containers

super26-Dec-02 2:20

super

26-Dec-02 2:20

I have a an MFC application in which I insert and OLE object(Word Document)
Now the problem is that I have an "View" Menu for my application with 6 submenu...So when I insert the Ole object..My Application Menu dissappears and "View" Menu of Microsoft word appears.So any idea how to merge two "View" menus...Is urgent

cheers,
Super
------------------------------------------
Too much of good is bad,mix some evil in it

hwnd and min?

imran_rafique26-Dec-02 1:18

imran_rafique

26-Dec-02 1:18

how to get a hwnd from an id ?
how to get minuttes from clock?

r00d0034@yahoo.com

Re: hwnd and min?

Anonymous26-Dec-02 2:37

Anonymous

26-Dec-02 2:37

????
To ask the right question you have to know part of the answer. Try to read books, it helps.

Re: hwnd and min?

Rickard Andersson²⁰26-Dec-02 2:47

Rickard Andersson²⁰

26-Dec-02 2:47

Anonymous wrote:
To ask the right question you have to know part of the answer.

What do you mean with this?
Why does he have to know some part of the answer? Doooh.
Tell me that part!

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Re: hwnd and min?

Anonymous26-Dec-02 2:55

Anonymous

26-Dec-02 2:55

It is like , when person loves "C#, ASP.NET and C++", but advises others to use gmtime instead of standard windows APIs.

Re: hwnd and min?

Rickard Andersson²⁰26-Dec-02 3:12

Rickard Andersson²⁰

26-Dec-02 3:12

And why didn't you mention that to him then, stupid "Anonymous"?
Do you know why forums are made? They are made to help people who asking for help.
You didn't help!
But I did... I can acknowledge that I forgot the Win32 API (GetSystemTime) because I've been to long inside the C Runtime Library now. But you knew about the Win32 API so, Why didn't you mention that? Doooooooooohh!!
BTW: Why are you anonymous? Don't you take responsibility for what you say?

Help or be quiet!

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Re: hwnd and min?

Anonymous26-Dec-02 3:22

Anonymous

26-Dec-02 3:22

Would you like my home address too? I did not mention anything because with your irresponsible answers you are breading ignorant programmers. This person obviously does not know anything about Windows or programming in general. By giving him this "quick fix" you produced yet another hacker, rest of us have to clean up after. This guy should read something, anything, before even coming here.

Re: hwnd and min?

Rickard Andersson²⁰26-Dec-02 3:55

Rickard Andersson²⁰

26-Dec-02 3:55

Anonymous wrote:
Would you like my home address too?

Not necessary.

Anonymous wrote:
I did not mention anything because with your irresponsible answers you are breading ignorant programmers.

Hm... I answered him with "Look up time(...) and gmtime(...) in MSDN Library....". That is an answer for what he were asking for! And the first one, that thing with HWND and ID I didn't understood so I asked what he meant with that. What did You answered him? Nothing! You said he had to know some damn part of the answer!!
Do I bread ignorant programmers??? You're so stupid!

Anonymous wrote:
This person obviously does not know anything about Windows or programming in general.

Right, then I told him to look up some functions that might be what he were looking for.
Better he look up things and read about it then I give him already written code!

Anonymous wrote:
By giving him this "quick fix" you produced yet another hacker, rest of us have to clean up after.

Hacker? ROTFLMAO! Laugh | :laugh:

We are talking about a way to get the minutes from time and how to get a HWND from some ID!

Anonymous wrote:
This guy should read something, anything, before even coming here.

Give him some advice then!
He may be don't have money to buy books and tutorials is hard to find, the good one is.

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Re: hwnd and min?

Rickard Andersson²⁰26-Dec-02 2:40

Rickard Andersson²⁰

26-Dec-02 2:40

imran_rafique wrote:
how to get a hwnd from an id ?

What kind of ID do you have?

imran_rafique wrote:
how to get minuttes from clock?

Look up time(...) and gmtime(..) in MSDN Library
nd not to forget, look up the tm struct also! Smile | :)

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Re: hwnd and min?

imran_rafique26-Dec-02 10:41

imran_rafique

26-Dec-02 10:41

say id of a button ?

r00d0034@yahoo.com

Re: hwnd and min?

Joaquín M López Muñoz26-Dec-02 21:19

Joaquín M López Muñoz

26-Dec-02 21:19

Maybe with GetDlgItem?

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

memory dc and scrolling problems:repost

Bonjo Kofi Ntini26-Dec-02 1:12

Bonjo Kofi Ntini

26-Dec-02 1:12

hi,

:-DI did not get convincing answer the last time.sorry if considered spam. Big Grin | :-D

I am drawing these engineering related drawings that need a lot of pre calculation for neat display before actually being rendered to the user.Every time.Zooming included.I (naturally) used CreateCompatibleDC() function,drew onto that, calculated stuff and continued from there.

The problem arises while scrolling.I set the scrolling sizes according to the bounds of the drawing plus spaces.The bound is calculated as said earlier.When i scroll, things get eaten away.However, moving the drawing slowly using the arrow keys works fine.

Why is this happening?Help.Drawing is the soul and life and ... of my sw

Kofi Ntini

Last row not visible

S O S26-Dec-02 0:57

S O S

26-Dec-02 0:57

I'm doing a MFC MDI app, with CScrollView view.
I am getting a very strange problem, the last row of the view is not visible until I resize the window in any way. I can scroll to the bottom, but it won't be visible until the window is resized(Even smaller, I can scroll there and it'll be drawn then)

This is how I set the scroll size
SetScrollSizes(MM_TEXT, CSize(1026, 1026),
CSize(64, 64),
CSize(1, 1));

Everything else draws fine though
This is how the last row is drawn

if (dc->RectVisible(CRect(CPoint(0, 1025), CSize(1026, 1))))
dc->FillSolidRect(0, 1025, 1026, 1, RGB(70, 70, 70));

Still happens if I do it without the RectVisible()

ON_NOTIFY(NM_RETURN, IDC_EDIT1,edit1Return)

Uffe Sundis26-Dec-02 0:33

Uffe Sundis

26-Dec-02 0:33

I can not get the above message to work in an ordinart CDialog messages map.
where the memberFxn looks like:
void edit1Return(NMHDR * pNotifyStruct, LRESULT * result )
{
MessageBox("Carrage return occured");
}

Must there be some kind of initializing in the program? Or how will I get the message to work?

Re: ON_NOTIFY(NM_RETURN, IDC_EDIT1,edit1Return)

Joaquín M López Muñoz26-Dec-02 3:51

Joaquín M López Muñoz

26-Dec-02 3:51

The dialog is intercepting the pressing of the enter key (and calling OnOK) before it gets to the focused control. You can try disabling the translation of enter hits as follows:

BOOL CYourDlg::PreTranslateMessage(MSG* pMsg) 
{
  if(pMsg->message==WM_KEYDOWN&&pMsg->wParam==VK_RETURN)return 0;
 
  return CDialog::PreTranslateMessage(pMsg);
}

but we warned that playing with PreTranslateMessage can lead to all sorts of strange behaviors with your app.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Change Mouse Cursor

nelzanoide26-Dec-02 0:20

nelzanoide

26-Dec-02 0:20

Does anybody know how to change the mouse cursor form ? I've been trying using lhCursor = AfxGetApp()->LoadStandardCursor(....) to change the cursor image, then SetCursor(lhCursor) make the change visible and finally OnSetCursor to stick with the changes whenever the mouve moves. The problem is that when the mouse leaves the window and comes backin again, it resets it's cursor to the old image, not the one I changed it to.

Thank you

Nelson Gonçalves

Re: Change Mouse Cursor

Joaquín M López Muñoz26-Dec-02 3:58

Joaquín M López Muñoz

26-Dec-02 3:58

Load the cursor once in OnInitDialog and set it every time OnSetCursor is called just like this:

BOOL CYourDlg::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message) 
{
  SetCursor(lhCursor);
  return TRUE;
}

I've tried it and it works OK.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Change Mouse Cursor

nelzanoide26-Dec-02 4:09

nelzanoide

26-Dec-02 4:09

Thank you. I've tried and it works. Smile | :)

Nelson Gonçalves

CArray woes

raner25-Dec-02 23:05

raner

25-Dec-02 23:05

Hi
I'm a VC beginner.I'm attempting to make use of the CArray template but i'm at a lost now.(i used CArray as the size of my array is not fixed)I declared a CArray object in my document class and wants to create a function so that other classes might access the array.

Below is an abstract of my program.

in CDocument header file, where m_array1 and GetRawDataArray are declared as public...
----------------

struct SRawData
{
double x;
double y;
};

CArray<srawdata, srawdata=""> m_array1;
CArray GetRawDataArray();

--------------------------------
in the CDocument .cpp file...
------------------------------

CArray CRainAttDoc::GetRawDataArray()
{
return m_array1;
}

this gives me the error message:
(a)error C2955: 'CArray' : use of class template requires template argument list
(b)error C2553: no legal conversion of return value to return type 'class CArray *'

Does anyone know what is happening and what i can do?
Thanks.

Re: CArray woes

KaЯl25-Dec-02 23:24

KaЯl

25-Dec-02 23:24

Try this:

in your header file, declare outside of the doc class declaration

typedef CArray <SRawData *, SRawData *> CSRawDataArray;

In the document class definition:

CSRawDataArray m_myDataArray;

Now you may use m_myDataArray like

SRawData *pNewData = new SRawData;
m_myDataArray.Add(pNewData);

while(m_myDataArray.GetCount())
delete m_myDataArray.RemoveHead()

HTH,

K.

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<hr color=#A0AFA0 width = 60% align=left><i>
One small village of indomitable geeks still holds out against the invaders. And life is not easy for the managers legionaries who garrison the fortified camps of Microsoftum, Javum, Ceplumplum and Vebasum</i></font>

Re: CArray woes

raner26-Dec-02 7:00

raner

26-Dec-02 7:00

haa ok

i said thks for your suggestion.gave me quite some insight really.But i still dunno how to create a function to return the array in some way so that other classes may access it.u have any suggestion on that?

Re: CArray woes

KaЯl26-Dec-02 7:26

KaЯl

26-Dec-02 7:26

There are several solutions:

* You may add public member functions to your document to manipulate the array from the outside of the document object
* You may directly "lend" the array to other classes like this:

CSRawDataArray &CMyDocument::GetArray()<br />
{<br />
     return m_myDataArray;<br />
}

Beware that this method returns a reference on the array, i.e. the "real" object, not a copy.

void COtherClass::AddData(CMyDocument *pDoc, CSRawDataArray *pData)<br />
{<br />
     CSRawDataArray &myArray = pDoc->GetArray();<br />
<br />
     myArray.Add(pData);<br />
}

HTH,

K.

One small village of indomitable geeks still holds out against the invaders. And life is not easy for the managers legionaries who garrison the fortified camps of Microsoftum, Javum, Ceplumplum and Vebasum

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