scroll bar in vc++ - C / C++ / MFC Discussion Boards

Re: Interacting with a Digital Camera

Jörgen Sigvardsson26-Oct-04 11:38

Jörgen Sigvardsson

26-Oct-04 11:38

std::fstream is the answer Poke tongue | ;-P

Seriously though, most cameras shows up as removable media in Windows 2k/XP. So all you need to do is to read the images as files (JPG, GIF, whatever the camera uses). Any other communication over the USB connection is probably proprietary, and is probably not disclosed without an NDA.

--
Weiter, weiter, ins verderben.
Wir müssen leben bis wir sterben.

Re: Interacting with a Digital Camera

markkuk26-Oct-04 12:30

markkuk

26-Oct-04 12:30

There's a standard protocol for communicating with non-mass storage digital cameras: PIMA/ISO 15740 Picture Transfer Protocol (PTP). Many cameras can be switched between mass storage and PTP modes.
There's an Open Source (GPL) library for communicating with PTP cameras: libptp See also the USB Still Image Capture Device Definition

Cancel button in window not working

Xzyx987X26-Oct-04 9:55

Xzyx987X

26-Oct-04 9:55

I wrote a set of functions for displaying a progress window while CopyFileEx() runs. The only problem is that the cancel button on the window won't work. Well, actually it will work if I display a message box right before I create the window, which I haven't been able to explain yet... Anyway, here is the full code for it, less the headers:

//Include files////////////////////////////////////////////////////////////////////////////

#include "global_definitions.h"

#include <windows.h>
#include <commctrl.h>
#include "debug.h"
#include "memory.h"
#include "stringio.h"
#include "window_classes.h"

///////////////////////////////////////////////////////////////////////////////////////////



//Function prototypes//////////////////////////////////////////////////////////////////////

void InitProgressWindowClass(void);

int CopyFileProgressEx(LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, DWORD dwCopyFlags, HWND hWndParent, char * title, char * message, BOOL popup, DWORD parentUpdate);

DWORD WINAPI ProgressWindowThread(LPVOID lParam);

INT_PTR CALLBACK ProgressWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

LRESULT ProgressWindow_OnCreate(HWND hWnd, WPARAM wParam, LPARAM lParam);

DWORD CALLBACK CopyProgressRoutine(LARGE_INTEGER TotalFileSize, LARGE_INTEGER TotalBytesTransferred, LARGE_INTEGER StreamSize, LARGE_INTEGER StreamBytesTransferred, DWORD dwStreamNumber, DWORD dwCallbackReason, HANDLE hSourceFile, HANDLE hDestinationFile, LPVOID lpData);

///////////////////////////////////////////////////////////////////////////////////////////



//Function definitions/////////////////////////////////////////////////////////////////////

void InitProgressWindowClass(void)
{

    WNDCLASSEX wc = {0};

	//Register the progress window class
    wc.cbSize         = sizeof(wc);
    wc.lpszClassName  = "Progress Window";
    wc.hInstance      = GetModuleHandle(NULL);
    wc.lpfnWndProc    = ProgressWindowProc;
    wc.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground  = (HBRUSH)GetSysColorBrush(COLOR_BTNFACE);
    wc.cbWndExtra     = sizeof(PROGRESSINFO *);

	RegisterClassEx(&wc);

}

int CopyFileProgressEx(LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, DWORD dwCopyFlags, HWND hWndParent, char * title, char * message, BOOL popup, DWORD parentUpdate)
{

	PROGRESSINFO * pip = ClearMemAlloc(sizeof(PROGRESSINFO));
	BOOL error;
	BOOL cancel = 0;
	DWORD threadId;

	if(!title)
		title = "";

	if(!message)
		message = "";

	pip->title = title;
	pip->message = message;

	pip->popup = popup;

	pip->cancel = &cancel;

	pip->hWndParent = hWndParent;

	pip->parentUpdate = parentUpdate;

	SetFocus(hWndParent);

	CreateThread(NULL, 0, ProgressWindowThread, pip, 0, &threadId);

	while(!pip->hWndProgress)
		Sleep(0);

	error = CopyFileEx(lpExistingFileName, lpNewFileName, CopyProgressRoutine, pip, NULL, dwCopyFlags);

	if(!error)
		return 1;
	else if(cancel)
		return 2;

	return 0;

}

DWORD WINAPI ProgressWindowThread(LPVOID lParam)
{

	MSG msg;
	DWORD exitCode = 0;
	PROGRESSINFO * pip = (PROGRESSINFO *) lParam;
	DWORD dwStyle = (pip->hWndParent != NULL ? WS_CHILD : 0) | WS_VISIBLE;
	RECT progressCords;

	if(pip->popup)
	{
		progressCords.left = GetSystemMetrics(SM_CXSCREEN) / 2 - PROGRESSWINDOW_WIDTH / 2;
		progressCords.top = GetSystemMetrics(SM_CYSCREEN) / 2 - PROGRESSWINDOW_HEIGHT / 2;

		dwStyle |= WS_POPUPWINDOW;
	}
	else
	{
		dwStyle |= WS_DLGFRAME;

		GetClientRect(pip->hWndParent, &progressCords);

		progressCords.left = (progressCords.right - progressCords.left) / 2 - PROGRESSWINDOW_WIDTH / 2;
		progressCords.top = (progressCords.bottom - progressCords.top) / 2 - PROGRESSWINDOW_HEIGHT / 2;
	}

	pip->hWndProgress = CreateWindowEx(
		0,
		"Progress Window",
		pip->title,
		dwStyle,
		progressCords.left,
		progressCords.top,
		PROGRESSWINDOW_WIDTH,
		PROGRESSWINDOW_HEIGHT,
		pip->hWndParent,
		NULL,
		GetModuleHandle(NULL),
		pip);

	while(GetMessage(&msg, NULL, 0, 0))
	{ 
		TranslateMessage(&msg); 
		DispatchMessage(&msg); 
	} 

	GetExitCodeThread(GetCurrentThread(), &exitCode);

	ExitThread(exitCode);

	ErrorMessage("Abnormal thread termination", NULL, NULL, MB_ICONEXCLAMATION, 1);

	return FALSE;

}

INT_PTR CALLBACK ProgressWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{

	switch(uMsg)
	{

	case WM_CREATE:
		return ProgressWindow_OnCreate(hWnd, wParam, lParam);
		break;

	case WM_COMMAND:
		switch(LOWORD(wParam))
		{

		case BN_CLICKED:
			*(((PROGRESSINFO *)(GetWindowLongPtr(hWnd, GWL_USERDATA)))->cancel) = 1;
			break;

		}
		break;

	case WM_CLOSE:
		DestroyWindow(hWnd);
		break;

	case WM_DESTROY:
		free((void *) GetWindowLongPtr(hWnd, GWL_USERDATA));
		break;

	}

    return DefWindowProc(hWnd, uMsg, wParam, lParam);

}

LRESULT ProgressWindow_OnCreate(HWND hWnd, WPARAM wParam, LPARAM lParam)
{

	PROGRESSINFO * pip = *(PROGRESSINFO **) lParam;
	RECT rect;

	SetWindowLongPtr(hWnd, GWL_USERDATA, (LONG) pip);

	GetClientRect(hWnd, &rect);

	pip->progressBar = CreateWindowEx(
		WS_EX_CLIENTEDGE,
		PROGRESS_CLASS,
		NULL,
		WS_CHILD | WS_VISIBLE | PBS_SMOOTH,
		rect.left + 2,
		PROGRESSWINDOW_HEIGHT / 2 - GetSystemMetrics(SM_CYVSCROLL),
		rect.right - 5,
		GetSystemMetrics(SM_CYVSCROLL),
		hWnd,
		0,
		GetModuleHandle(NULL),
		NULL);

	pip->hWndStatic = CreateWindowEx(
		0,
		"Static",
		NULL,
		WS_CHILD | WS_VISIBLE | SS_CENTER,
		rect.left + 2,
		rect.top + 10,
		rect.right - 5,
		rect.top + 20,
		hWnd,
		0,
		GetModuleHandle(NULL),
		NULL);

	SetWindowText(pip->hWndStatic, pip->message);

	pip->hWndCancel = CreateWindowEx(
		0,
		"Button",
		NULL,
		WS_CHILD | WS_VISIBLE | BS_TEXT | BS_PUSHBUTTON,
		((rect.right - rect.left) / 2) + rect.left - 30,
		rect.bottom  - 30,
		60,
		24,
		hWnd,
		0,
		GetModuleHandle(NULL),
		NULL);

	SetWindowText(pip->hWndCancel, "Cancel");

	pip->hWndProgress = hWnd;

	SetFocus(pip->hWndCancel);

	return FALSE;

}

DWORD CALLBACK CopyProgressRoutine(LARGE_INTEGER TotalFileSize, LARGE_INTEGER TotalBytesTransferred, LARGE_INTEGER StreamSize, LARGE_INTEGER StreamBytesTransferred, DWORD dwStreamNumber, DWORD dwCallbackReason, HANDLE hSourceFile, HANDLE hDestinationFile, LPVOID lpData)
{

	int i;
	unsigned __int64 biasBit = 0x8000000000000000;
	int progressRange;
	int progressAchieved;
	PROGRESSINFO * pip = lpData;

	if(!pip->progressBias)
	{
		if(!(TotalFileSize.QuadPart & 0xFFFFFFFF80000000))
			pip->progressBias = 0;

		else  //Untested...
		{
			for(i = 33; i; i--)
			{
				if(biasBit & TotalFileSize.QuadPart)
					break;

				biasBit = biasBit>>1;
			}

			pip->progressBias = 32 - i;
		}
	}

	progressRange = (int) (TotalFileSize.QuadPart>>(pip->progressBias + 1));

	progressAchieved = (int) (TotalBytesTransferred.QuadPart>>(pip->progressBias + 1));

	SendMessage(pip->progressBar, (UINT) PBM_SETRANGE32, (WPARAM) 0, (LPARAM) progressRange);

	SendMessage(pip->progressBar, (UINT) PBM_SETPOS, (WPARAM) progressAchieved, (LPARAM) 0);

	if(pip->parentUpdate && pip->lastParentUpdate + pip->parentUpdate >= GetTickCount())
		UpdateWindow(pip->hWndParent);

	pip->lastParentUpdate = GetTickCount();

	if(TotalFileSize.QuadPart == TotalBytesTransferred.QuadPart)
	{
		PostMessage(pip->hWndProgress, WM_CLOSE, 0, 0);
		return PROGRESS_CONTINUE;
	}

	if(*pip->cancel)
	{
		PostMessage(pip->hWndProgress, WM_CLOSE, 0, 0);
		return PROGRESS_CANCEL;
	}
	else
		return PROGRESS_CONTINUE;

}

///////////////////////////////////////////////////////////////////////////////////////////

Streaming Audio

nlecren26-Oct-04 9:09

nlecren

26-Oct-04 9:09

Anyone know of any samples on how to write a streaming audio server??

Re: Streaming Audio

NietzscheDisciple26-Oct-04 9:45

NietzscheDisciple

26-Oct-04 9:45

Check out the DirectSound samples in the DirectX SDK.

The SDK does not provide an out-of-the-box streaming server solution. However the examples (in native C++ and in C#) give you a good introduction to the handling the audio data.

Can't comment about the network aspects.

Re: Streaming Audio

dharani26-Oct-04 21:14

dharani

26-Oct-04 21:14

Do u mean u want to stream uncompressed PCM format? if so u can refer Multimedia SDK .

Dharani babu S

redindian

sscanf question

act_x26-Oct-04 8:58

act_x

26-Oct-04 8:58

say i have
char strdata[100];
strcpy(strdata,"0.0000136");
float f;

the call
sscanf(strdata,"%f",&f) ; // works ok (ie f gets the correct value)
// but I cannot get

// need precision upto 6 places
sscanf(strdata,"%.6f",&f) ;

// I need formatted input
// to work
Please help .

scroll bar in vc++

Araj0126-Oct-04 8:50

Araj01

26-Oct-04 8:50

I have a graph which plots 14 million points. I want to include a scroll bar which would be sized based on the visible portion of the graph. initally all 14 million points are displayed. User can then use zoom function to zoom the graph where a max of 450 points can be seen. I am not able to include the scroll bar function. can anyone tell me what are the properties i need to set in the Scrollbar info structure?

thanks,

How to return string type in class

Cramp26-Oct-04 8:47

Cramp

26-Oct-04 8:47

First, I really appreciate that you spend your time to read my question.

Hi! I try to build a class that has several functions. Some of them will return string.
But my complier say I have something wrong.
The complier show the message that undefine error.
Please help me to figure out. Thank you.

I paste my complete code below

// filename:studentinfo.h
class studentinfo
{
public:
void set_lastname(string);
void set_firstname(string);
void set_ssn(string);
void set_age(int);
void set_phone(string);
string show_lastname();
string show_firstname();
string show_ssn();
int show_age();
string show_phone();
private:
string lastname;
string firstname;
string ssn;
int age;
string phone;
};
// filename:studentinfo.cpp
#include <iostream>
#include <string>
#include "studentinfo.h"
//--------------------------------------------------------------------------------
// The following functions declare for my class.
//--------------------------------------------------------------------------------
string studentinfo::show_lastname()
{
return lastname;
}
string studentinfo::show_firstname()
{
return firstname;
}
string studentinfo::show_ssn()
{
return ssn;
}
int studentinfo::show_age()
{
return age;
}
string studentinfo::show_phone()
{
return phone;
}
void studentinfo::set_lastname(string text)
{
lastname=text;
}
void studentinfo::set_firstname(string text)
{
firstname=text;
}
void studentinfo::set_ssn(string text)
{
ssn=text;
}
void studentinfo::set_age(int number)
{
age=number;
}
void studentinfo::set_phone(string text)
{
phone=text;
}

Re: How to return string type in class

LeeeNN26-Oct-04 8:57

LeeeNN

26-Oct-04 8:57

Are you sure it's string not CString? Laugh | :laugh:

Re: How to return string type in class

Nemanja Trifunovic26-Oct-04 8:59

Nemanja Trifunovic

26-Oct-04 8:59

Replace string with std::string

My programming blahblahblah blog. If you ever find anything useful here, please let me know to remove it.

Re: How to return string type in class

markkuk26-Oct-04 9:18

markkuk

26-Oct-04 9:18

The standard string type is std::string, you can add using namespace std; after the includes to avoid adding the std:: prefix everywhere.

time critical

LeeeNN26-Oct-04 8:19

LeeeNN

26-Oct-04 8:19

is there any way to guarantee a PC thread run at 200ms+_100ms period interval? Timer or multimedia timer seems don't fit.

Confused | :confused:

Re: time critical

Xzyx987X26-Oct-04 9:45

Xzyx987X

26-Oct-04 9:45

Well, there's always the Sleep() funtion. I'm not sure how gurenteed the amount of time it waits is though.

Edit: Just checked. It's not gurenteed to resume excecution after the given time period, but you could probobly fix that with a heavy priority boost or something.

Re: time critical

LeeeNN26-Oct-04 10:34

LeeeNN

26-Oct-04 10:34

Yes I set the thread to high priority, it still won't guarantee. by the way, what is heavy priority boost? Confused | :confused:

Re: time critical

Nemanja Trifunovic26-Oct-04 16:07

Nemanja Trifunovic

26-Oct-04 16:07

I told you in a previous post that you can't have any such guarantees with a non-realtime OS like Windows. If you don't trust me, read this article[^].

Can you use some RTOS, like QNX[^]?

My programming blahblahblah blog. If you ever find anything useful here, please let me know to remove it.

using MFC in win32 application

includeh1026-Oct-04 7:33

includeh10

26-Oct-04 7:33

I have a win32 app and copy MFC code into it.
but the app can not be compiled now because of MFC classes.
MFC is in "Use MFC in a static library".

how to change settings for compiling?

thx

includeh10

Re: using MFC in win32 application

Christian Graus26-Oct-04 8:49

Christian Graus

26-Oct-04 8:49

Create two Win32 apps, tick 'use MFC' for one. Diff the files, and make sure you have all those things set in your own code.

Christian

I have several lifelong friends that are New Yorkers but I have always gravitated toward the weirdo's. - Richard Stringer

DialogBar in a DLL? Please help!

Exe026-Oct-04 7:27

Exe0

26-Oct-04 7:27

Hi there!

I've got a problem with a simple, self-written DialogBar.

The DialogBar is not amazing at all, it simply displays a Dialog in a dockable ControlBar and is part of a DLL. If I try to create the DialogBar (in my MainFrame-Class), it fails and the control bar can not be created.

After a little research, I found out that the following line in the MFC-Core failed:

 <br />
HWND hWnd = ::CreateWindowEx(cs.dwExStyle, cs.lpszClass,<br />
   cs.lpszName, cs.style, cs.x, cs.y, cs.cx, cs.cy,<br />
   cs.hwndParent, cs.hMenu, cs.hInstance, cs.lpCreateParams);<br />

Another strange thing I found out while researching:

 <br />
m_wndDialog.Create("bla fasel", this, 123456, WS_VISIBLE|WS_CHILD|CBRS_FLYBY|CBRS_SIZE_DYNAMIC|CBRS_TOOLTIPS)<br />

In that line a pointer to the parent window is passed to the Create() method (here this) of the DialogBar which is in the DLL.
If I verify the this-pointer before I enter the Create() method the member m_hWnd is valid and seems to be correct. But if I enter the Create() method (is a call to the DLL method), the m_hWnd of the parent window pointer becomes NULL.

Anybody out there with a solution to the problem?

Thanks in advance!
Axel

A method to collapse code in the IDE

NietzscheDisciple26-Oct-04 7:17

NietzscheDisciple

26-Oct-04 7:17

While coding in C# in the Visual Studio .NET 2003 IDE, one is able to mark regions using #region and #endregion.

Is a similar option available when coding in Visual C++?

Re: A method to collapse code in the IDE

BlackDice26-Oct-04 10:03

BlackDice

26-Oct-04 10:03

you should be able to right-click in your editor window, go to 'Outlining' on the popup menu, and get a list of options there.

Who are all these people and what are they doing in my house?...Me in 30 years, inside a grocery store

My articles[^]
bdiamond Sleepy | :zzz:

Menu on CFormView Derived

aman200626-Oct-04 6:27

aman2006

26-Oct-04 6:27

Hi
I have some 4 views all derived from CFormView. There is no system default menu in all. But i want to hang one menu in one of the view like Tools-->Copy.

I tried some options but it is failed. Can anybody tell me how to create this menu using CMenu class or with some other method??

Thanks in advance
Shailesh

Knowing resource ID

0v3rloader26-Oct-04 6:02

0v3rloader

26-Oct-04 6:02

Hello,

Given a CDocument object, how does one do about knowing the ID of the resource (the IDR_resource) which was associated to the document template?

Thanks,

David

long compile time ... vs.net 2003 ...

Maximilien26-Oct-04 5:57

Maximilien

26-Oct-04 5:57

I have a project that is taking WAAAAYYYY too much time to compile... ( IMHO )

all files are C++ and are using precompile headers.

I use Program Database ( Zi ), minimal build ( and link ).

the only thing that I'm not sure, is that some of my source files are in subfolders of the main project file, and do

#include "../stdafx.h"

can that be a problem ?

also, there's a vc7.idb and vc7.pdb that are created ( and recreated ) quite often, I assume that the .pdb is the program database, but is it supposed to be recreated at every couple of files ?

THanks.

Maximilien Lincourt
Your Head A Splode - Strong Bad

Re: long compile time ... vs.net 2003 ...

Blake Miller26-Oct-04 6:02

Blake Miller

26-Oct-04 6:02

With minimal build and link enabled, it can take longer and longer to compile and link because certain files are hashed, instead of being rewitten every time. You might try a FULL rebuild (or rebuild all) periodically to keep this thrashing to a minimum. I see this same problem with VC 6.0 when I have incremental link enabled.

The PDB must correlate the lines in your source with the locations on the executables, so it is common for that to rebuild each time you recompile and relink.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.