C / C++ / MFC

[solved]Re: tracking down linker errors

27-Aug-22 6:44

If you actually provide some details then maybe we can help.

Calin Negru27-Aug-22 8:01

Calin Negru

27-Aug-22 8:01

I`m not sure what details you are expecting. All I have in the build output window is a one line message:
1>Tutorial07.obj : error LNK2001: unresolved external symbol "void __cdecl CheckCollisions(class std::vector<class gameelement="" *,class="" std::allocator<class="" *=""> > *,int,class contim *,int)"

I know an error of this type means that some parameters don`t match in the function definition, declaration and the place where the function is being used. I did a search for the function name within the code file, everything seems to be fine in the function header (return type, function name and parameters) everywhere. I need more details to know what exactly doesn`t match.

void CheckCollisions(vector<gameelement * > * GAllElements, int UnitCount, contim* OldNewTable,int frame);

never mind I found the error, it was a parameter mismatch, you have to be extra careful with those.

modified 27-Aug-22 15:51pm.

Using nlohmann JSON to insert more data

Kiran Satish26-Aug-22 7:03

Kiran Satish

26-Aug-22 7:03

I have a json file genrated in python from another system that needs to be read/updated in another MFC application. I can successfully read the existing data from the json file using nlohmann json add-in. For example, the file consists of two data fields with one field having any array of two subfields as below

C++

{
  "city_data":[
     {
       "t":"m",
       "l":[12.0,10.3,0.0,1.0]
     },
     {
       "t":"l",
       "l":[10.1,20.37,0.0,1.0]
     },
     {
       "t":"l",
       "l":[47.82,4.63,0.0,1.0]
     },
     {
       "t":"m",
       "l":[67.66,43.33,0.0,1.0]
     }
   ],
   "map_data":"JZDKZTCaTyWQymUwmk8lkMplMJpPJZDKZTCaTyWQymUwmk/8/+n8AVAZ1WCxk8rYAAAAASUVORK5CYII="
}

The "map_data" is basically base64 encoded png image.
I would like to add more entries into "city_data" field as {"t":"x","l":[0.0,0.0,0.0,0.0]} while the "map_data" stays the same. Then I can write the json object into a new file with updates.

To read the json file,

C++

std::ifstream f(file);
json data = json::parse(f);

To retreive "city_data" and then its type and location

C++

json& cityInfo = data["city_data"];
for (unsigned int i = 0; i < cityInfo.size(); i++)
        {
            json& cityType = cityInfo[i];
            std::string ctyTyp = cityType["t"];
            json& cityLoc = cityType["l"];
            std::float_t x = cityLoc[0];
            std::float_t y = cityLoc[1];
            // do something with the retrieved values      
        }
//To retreive map data
ofstream outfile;
outfile.open(m_strFolderPath + m_strFileName + ".png", ofstream::binary);
std::string mapFrame = data["map_data"];
string temp = base64_decode(mapFrame );
outfile.write(temp.c_str(), temp.size());
outfile.close();
f.close();

Any suggestions on how to insert new city_data fields into the nlohmann JSON object? or a way to create a new json file like in above format?
thanks

PKNT

modified 26-Aug-22 14:17pm.

Re: Using nlohmann JSON to insert more data

Mircea Neacsu26-Aug-22 8:53

Mircea Neacsu

26-Aug-22 8:53

I haven't used nlohmann json in a while (because I've made my own - see mlib/json.h at master · neacsum/mlib · GitHub[^]

However I think this should work:

C++

// do something with the retrieved values
cityInfo[i]["newval"] = to_string (i + 1);

--EDIT--
I read your message again and realized you want to extend the cityInfo array. In this case you would simply write something like:

C++

cityInfo[4] = json::parse(R"({"t":"x", "l" : [0.0, 0.0, 0.0, 0.0] })");

Mircea

modified 26-Aug-22 21:09pm.

Question About CToolTipCtrl

ForNow24-Aug-22 8:33

24-Aug-22 8:33

Hi
I have some question about the class. I would like to use it on My CRichEditctrl where the source code is for my debugger.

There are CWnd members in a number of the methods in the class would that in my case be the CrichEditCtrl in Addition the HiTest api which has a CPoint member is that point relative to (in my case) the CRichEditCtrl

Thanks

Victor Nijegorodov24-Aug-22 21:53

24-Aug-22 21:53

Umm, could you formulate your question(s) a bit more clear?

ForNow24-Aug-22 22:19

24-Aug-22 22:19

I’ll ask a more specific question the create api of the CtooltipCtrl class has 2 parameters CWnd and dwstyle

I would like to use it in my derived CrichEditctrl class whose parent is a CDialog should the Cwnd be the CRichEditrl or The CDialog

Thanks

Victor Nijegorodov24-Aug-22 23:56

24-Aug-22 23:56

It depends upon what and how are you going to display tooltips for your control.
If it would be some text for the whole control then pass the CDialog CWnd* (in this case you will handle the TTN_NEEDTEXT notification in the dialog class).
If the tooltip text would depend on some position or some content within the controls then it could be better passing the control CWnd* (then you will handle the TTN_NEEDTEXT notification in the control's class).

ForNow25-Aug-22 1:36

25-Aug-22 1:36

Maybe its best if I used as an example if I have the following text in my CrichEditctrl

D203 B11A 801C 0011A 0001C MVC FIELDA,FILEDB

and I however the mouse over FIELDB which has a value of X'00000003' I would like the tool tip control to display it much like the visual studio debugger

Hope this makes sense

thanks

Victor Nijegorodov25-Aug-22 2:18

25-Aug-22 2:18

Then you should create the tooltip control within your CrichEditctrl class passing the CrichEditctrl CWnd* as the parent.
Then you would have to implement some handling (the mouse move - ?) procedure to determine what text is to be displayed in tooltip. If the will be some (new!) text then use the following CToolTipCtrlmethods:
UpdateTipText
TrackPosition
TrackActivate

Victor Nijegorodov25-Aug-22 2:44

25-Aug-22 2:44

This article with a code and example would be a good start: XTipComboBox - Display tooltips for combobox

ForNow25-Aug-22 3:01

Properly document C++ code for use in Intellisense ?

25-Aug-22 3:01

THANK YOU

Maximilien22-Aug-22 5:14

Maximilien

22-Aug-22 5:14

Using VS2019 (/std:c++20) and VS2022

I'm trying to formally document some code in header files.

Most of the time, adding comments does not seem to work properly in Intellisense.

What is the proper C++ comment format ?

This is mostly used to generate offline documentation (as far as I can see) and does not plays well with intellisense.

Seems sometimes intellisense breaks down and does not fully display or does not format the comments in the info tooltips.

For example :

sometimes this works or not:

C++

/// Application arguments.
struct ApplicationArguments {};

sometimes this works or not :

C++

/// <summary>
/// Application arguments.
/// </summary>
struct ApplicationArguments {};

I'm kind of baffled.

CI/CD = Continuous Impediment/Continuous Despair

Re: Properly document C++ code for use in Intellisense ?

Richard MacCutchan22-Aug-22 21:28

Need insight as to how VS2008 parses vcproj files

22-Aug-22 21:28

That is the format I use and it seems to work fine. However, I have noticed with some of the system functions that a double slash works as well.

charlieg21-Aug-22 8:45

Re: Need insight as to how VS2008 parses vcproj files

21-Aug-22 8:45

elephant me.

First, don't tell me to upgrade, for this project I'm stuck on VS2008 for an embedded project. From time to time, I need to move a development project to new hardware. Lets say I start on LAPA (laptop A) and I copy it to LAPB. When I open the project (we'll call it Fred and my user name is chg) on LAPB, I now have to user project files in the folder:

- Fred.vcproj
- Fred.vcprog.LAPA.chg.user
- Fred.vcprog.LAPB.chg.user

Now I can see VS loading fred.vcproj and then adding a specific user's settings - sort of - but I cannot come up with a good reason why the machine name would be included. In any event, on LAPB, I would expect to pick up those settings. Instead, I find that some of my project settings have changed:

- Deployment changes from the old setting to %CSIDL_PROGRAM_FILES%\fred.exe
- Debugging remote executable changes from the default to %CSIDL_PROGRAM_FILES%\fred\fred.exe

for ALL targets.

This would be a minor irritation if we were just talking about my example, but my actual application has over 80.

Comparing the user vcproj files, I see where the RemoteMachine has changed as well as the RemoteExecutable. But if I update these in the new LAPB project file, I still get %CSIDL_PROGRAM_FILES% inserted.

Any insight before I start slogging through this crap?

some of my deployment settings default to whatever MS deems appropriate.

Charlie Gilley

“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759

Has never been more appropriate.

modified 21-Aug-22 14:59pm.

Mircea Neacsu21-Aug-22 10:35

Mircea Neacsu

21-Aug-22 10:35

With the disclaimer that I couldn't possibly try my suggestion on VC2008 (got rid of it long time ago) here is how I handle a similar issue.

- Keep everything under Git source control
- Add *.user to .gitignore
- Have everything setup once the way you like it on LAPA and LAPB.

Now every time you want to transfer from LAPA to LAPB you do git push on LAPA and git pull on LAPB. That keeps all *.user files the way you set them.

Mircea

Re: Need insight as to how VS2008 parses vcproj files

charlieg22-Aug-22 0:56

Re: Need insight as to how VS2008 parses vcproj files

22-Aug-22 0:56

Reasonable suggestion, but let's say I create a LAPC? Or I give the project to another developer?
He/she then run into the exact same issue.

Charlie Gilley

“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759

Has never been more appropriate.

Mircea Neacsu22-Aug-22 1:45

Mircea Neacsu

22-Aug-22 1:45

Newer versions of VS can run happily without *.user file. If it's missing it will be recreated with some reasonable defaults. So in your case if you go to LAPC you do a git pull and than, the first time, you will have to adjust the .user file to your liking. After that it will stay on that machine.

Mircea

Re: Need insight as to how VS2008 parses vcproj files

charlieg22-Aug-22 1:53

Re: Need insight as to how VS2008 parses vcproj files

22-Aug-22 1:53

You would *think* that. Even though it's obvious what changed, I can set that and it still misbehaves. I'll keep digging.

Charlie Gilley

“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759

Has never been more appropriate.

charlieg28-Mar-23 9:40

DialogBox fuction not executing its procedure [SOLVED]

28-Mar-23 9:40

Dusting this gripe off and putting it to bed.

For a certainty, VS2008 creates project files on a per system and person basis. It is what it is.

After multiple occurrences of having to slog through this nonsense, I finally came across the Import and Export Settings Wizard.

Go to Tools -> Import Export and follow the steps. I have yet to find any documentation from Microsoft that starts with "So, you're moving to a new machine..."

Charlie Gilley

“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759

Has never been more appropriate.

coco24318-Aug-22 23:39

coco243

18-Aug-22 23:39

Hi,

I am trying to compile a project who use message crackers and is different from those wich I am used with(those projects that uses WindProc procedure and the other functions automatically created by the VS IDE)

This is the windows main function where I call DialogBox function:

C++

int WINAPI WinMain(HINSTANCE hinstExe, HINSTANCE hinstPrev, LPSTR pszCmdLine, int nCmdShow)
{


DialogBox(hinstExe, MAKEINTRESOURCE(IDD_DIRWALK), NULL, Dlg_Proc);

return(0);
}

If I place a breakpoint on the Dlg_Proc preocedure, the program never goes there to start it:

C++

BOOL CALLBACK Dlg_Proc (HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	switch (uMsg)
	{
	chHANDLE_DLGMSG(hwnd, WM_INITDIALOG, Dlg_OnInitDialog);
	chHANDLE_DLGMSG(hwnd, WM_SIZE, Dlg_OnSize);

	}

	return(FALSE);
}

Here is the resource for the dialog box:

C++

// Dialog
IDD_DIRWALK DIALOG DISCARDABLE 10, 18, 250, 250
STYLE WS_MINIMIZEBOX | WS_MAXIMIZEBOX | WS_POPUP|
              WS_VISIBLE| WS_CAPTION | WS_SYSMENU |WS_THICKFRAME
CAPTION "Directory Walk"
FONT 8, "System"
BEGIN
       LISTBOX     IDC_TREE,0,0,0,0,NOT LBS_NOTIFY |
	                      LBX_NOINTEGRAL_HEIGHT | NOT WS_BORDER |
			   WS_VSCROLL | WS_HSCROLL | WS_GROUP |
			   WS_TABSTOP
END

Here is the macro definition for messages:

C++

#define chHANDLE_DLGMSG(hWnd, message, fn)                                         \
	case (message):                                                                \
return (SetDlgMsgResult(hwnd, uMsg, HANDLE_##message((hwnd),  (wParam), (lParam), (fn))))

I don't think that the problem could be on the resource code for dialog box as long as the program even don't execute de
dialog box procedure.

If you know where the problem could be, please help me.

Thank you,

modified 23-Aug-22 12:32pm.

Richard MacCutchan19-Aug-22 0:38

19-Aug-22 0:38

I think you are missing the DS_MODALFRAME style from your dialog template. And your message handlers could contain anything - we cannot see the code. As I already suggested to you, get rid of these big defines and put the source in your handler. You will then at least have a chance of finding out what is wrong, as will we. And a better place to learn how to code for Dialogs is at About Dialog Boxes - Win32 apps | Microsoft Docs[^.

coco24319-Aug-22 1:14

coco243

19-Aug-22 1:14

Thank you for your response, unfortunately not DS_MODALEFRAME is the problem

The problem is ( I think ), that when DialogBox function is called in WinMain, its associated procedure function Dlg_ProcDlg_Proc isn't executed.

Richard MacCutchan wrote:
And your message handlers could contain anything - we cannot see the code.

Are you reffering to Dlg_OnInitDialog as message handlers? It's code is:

C++

BOOL Dlg_OnInitDialog (HWND hwnd, HWND hwndFocus, LPARAM lParam)
{
	RECT rc;

	// Associate an icon with the dialog box.
	chSETDLGICONS(hwnd, IDI_DIRWALK, IDI_DIRWALK);
    
    // here is some code that I didn't got to, or have patience to write

	GetClientRect(hwnd, &rc);
	SetWindowPos(GetDlgItem(hwnd, IDC_TREE), NULL, 0, 0, rc.right, rc.bottom, SWP_NOZORDER);

	return(TRUE);
}

And the macro for chSETDLGICONS(hwnd, IDI_DIRWALK, IDI_DIRWALK); Big Grin | :-D

is:

<pre lang="C++">

#define chINITSTRUCT(structure, fInitSize)                       \
        (ZeroMemory(&(structure), sizeof(structure)),             \
	fInitSize ? (*(int*) &(structure) = sizeof(structure)) : 0)

// Dialog Box Icon Setting Macro
// The call to SetClassLong is for Windows NT 3.51 or less.
// The WM_SETICON messages are for Windows NT 4.0 and Win 95
#define chSETDLGICONS(hwnd, idiLarge, idiSmall)                  \
		{                                                              \
		OSVERSIONINFO VerInfo;                                      \
		chINITSTRUCT(VerInfo, TRUE);                             \
		GetVersionEx(&VerInfo);                                  \
		if ((VerInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) &&   \
			(VerInfo.dwMajorVersion <=3 &&                      \
			VerInfo.dwMinorVersion <= 51))                       \
		{                                                        \
			SetClassLong(hwnd, GCL_HICON, (LONG)                      \
				LoadIcon(GetWindowInstance(hwnd),                \
				MAKEINTRESOURCE(idiLarge)));                     \
		}                                                        \
		else                                                    \
		 {                                                       \
			 SendMessage(hwnd, WM_SETICON, TRUE, (LPARAM)        \
				 LoadIcon(GetWindowInstance(hwnd),                    \
				 MAKEINTRESOURCE(idiLarge)));                    \
			 SendMessage(hwnd, WM_SETICON, FALSE, (LPARAM)       \
				 LoadIcon(GetWindowInstance(hwnd),                    \
				 MAKEINTRESOURCE(idiSmall)));                    \
		}                                                        \
	}

But the program dosen't reach the Dlg_OnInitDialog, I placed a breakpoint there.

What do I miss? If it is really necessary for the clearness of the code I wll add and the macros in code.

And guys please don't get upset on me because I insist to solve this old kind of program, but I am curious about this different style of managing windows messages and please help me to go through.

Thank you Smile | :)

Richard MacCutchan19-Aug-22 1:47

19-Aug-22 1:47

coco243 wrote:
But the program dosen't reach the Dlg_OnInitDialog, I placed a breakpoint there.

Where is the code for chHANDLE_DLGMSG? I keep telling you to get rid of these ridiculous #define statements; they are just making it more difficult to see what is happening.