Simple Problem? Blind Author cant see? - C / C++ / MFC Discussion Boards

CScrollView doesn't respond to mousewheel or keyboard

SeniorBob14-Mar-07 13:22

14-Mar-07 13:22

Hello,

I'm having a problem with a CScrollView in a CSplitterWnd. It doesn't respond to any keyboard commands (WM_KEYDOWN) or to WM_MOUSEWHEEL. The CSplitterWnd is a 1 row, 2 col splitter. The left side (0,0) is a CFormView and the right side (0,1) is the CScrollView (CMessageView : CScrollView). Unfortunately CMessageView originally inherited from just a CView and I later changed it to inherit from CScrollView by manually changing all the CView references to CScrollView, except where there was a pointer to CView. This may be an underlying cause to the problem.

Anyway the scrollview responds properly to the use of the scrollbars, but doesn't respond to the keyboard or mousewheel. I've been able to determine that the CMessageView does indeed have focus and that it does in fact receive WM_MOUSEWHEEL commands. I haven't tried WM_KEYDOWN commands, but I suspect that it will respond to them as well.

Does anyone have any ideas on what I'm doing wrong? Or some suggestions on other things to try? I've googled on this for quite a while now and nothing that I've found seems to work. I thought that a CScrollView was supposed to automatically work with mouse wheels and the keyboard.

Thanks in advance for any help.

im just learning to prgram and have troubleing starting this question

bigtimer102214-Mar-07 12:32

bigtimer1022

14-Mar-07 12:32

Write a program which outputs frequency of digits in a given integer. For example, if the number is 12424329, output will be
Number Frequency
1 (space) 1
2 (space) 3
3 (space) 1
4 (space) 2
9 (space) 1
Use a switch statement to obtain frequency of the digits.

im goin to try and work on it right now and see if i can get through just asking for alittle help thanks...
(space) doesn't mean anything just to make the numbers line up

Re: im just learning to prgram and have troubleing starting this question

Bram van Kampen14-Mar-07 16:30

Bram van Kampen

14-Mar-07 16:30

Reading your exam question properly is probably a good start. Learning how to Copy and Paste it on this Message Board would count as a good second, at least people would know what the question is about, A good Third would be to realise that this message board is NOT about doing your exam work for you, Point four is, If you ask a question that NoOne can understand, Don't expect a sebsible answer.

Moral of the story: Read Books about CPP,C,Operating Systems, Anything you can get your hands at.Alternatively, Enroll in a Course and hang on to every word said. They call that Studying.

When you're finished doing reading and doing courses, Read More Books, Enroll to More courses. There's No Shortcut to Knowledge.

LateNightsInNewry

Re: im just learning to prgram and have troubleing starting this question

_AnsHUMAN_ 14-Mar-07 18:52

_AnsHUMAN_

14-Mar-07 18:52

I think I provided you with the logic[^] a day or two before.

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: im just learning to prgram and have troubleing starting this question

bigtimer102214-Mar-07 18:54

bigtimer1022

14-Mar-07 18:54

#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;

int n, temp, count0 = 0, count1 = 0, count2 = 0, count3 = 0, count4 = 0, count5 = 0, count6 = 0, count7 = 0, count8 = 0, count9 = 0;

int main()
{
cout << "Enter the number to be evaluated." << endl;
cin >> temp;
while (temp != 0){
n=temp%10;
switch(n){
case 0: count0++;
break;
case 1: count1++;
break;
case 2: count2++;
break;
case 3: count3++;
break;
case 4: count4++;
break;
case 5: count5++;
break;
case 6: count6++;
break;
case 7: count7++;
break;
case 8: count8++;
break;
case 9: count9++;
break;
}
temp = temp / 10;

}
cout << " Answer is " << endl;
if(count0>0)
cout<< "0" << " " << count0 << endl;
if(count1>0)
cout<< "1" << " " << count1 << endl;
if(count2>0)
cout<< "2" << " " << count2 << endl;
if(count3>0)
cout<< "3" << " " << count3 << endl;
if(count4>0)
cout<< "4" << " " << count4 << endl;
if(count5>0)
cout<< "5" << " " << count5 << endl;
if(count6>0)
cout<< "6" << " " << count6 << endl;
if(count7>0)
cout<< "7" << " " << count7 << endl;
if(count8>0)
cout<< "8" << " " << count8 << endl;
if(count9>0)
cout<< "9" << " " << count9 << endl;

return 0 ;
}

Re: im just learning to prgram and have troubleing starting this question

_AnsHUMAN_ 14-Mar-07 19:03

_AnsHUMAN_

14-Mar-07 19:03

<code>
int _tmain(int argc, _TCHAR* argv[])
{
	int number;
	cout<<"Please enter the number-";
	cin>>number;
	int temp,r;
	int count=0;
	bool numberFound=false;
	for(int i=0;i<=9;i++)
	{
		count=0;
		temp=number;
		while(temp!=0)
		{
			r=temp%10;
			temp=temp/10;
			if(r==i)
			{
				count++;
				
			}
		}
		if(count>0)
			cout<<i<<" " <<count<<endl;
	}
	return 0;
}

You can modify this to use switch case

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: im just learning to prgram and have troubleing starting this question

bigtimer102214-Mar-07 19:03

bigtimer1022

14-Mar-07 19:03

i think it right im just checking...
and i did copy it and paste it right...

#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;

int n, temp, count0 = 0, count1 = 0, count2 = 0, count3 = 0, count4 = 0, count5 = 0, count6 = 0, count7 = 0, count8 = 0, count9 = 0;

int main()
{
cout << "Enter the number to be evaluated." << endl;
cin >> temp;
while (temp != 0){
n=temp%10;
switch(n){
case 0: count0++;
break;
case 1: count1++;
break;
case 2: count2++;
break;
case 3: count3++;
break;
case 4: count4++;
break;
case 5: count5++;
break;
case 6: count6++;
break;
case 7: count7++;
break;
case 8: count8++;
break;
case 9: count9++;
break;
}
temp = temp / 10;

}
cout << " Answer is " << endl;
if(count0>0)
cout<< "0" << " " << count0 << endl;
if(count1>0)
cout<< "1" << " " << count1 << endl;
if(count2>0)
cout<< "2" << " " << count2 << endl;
if(count3>0)
cout<< "3" << " " << count3 << endl;
if(count4>0)
cout<< "4" << " " << count4 << endl;
if(count5>0)
cout<< "5" << " " << count5 << endl;
if(count6>0)
cout<< "6" << " " << count6 << endl;
if(count7>0)
cout<< "7" << " " << count7 << endl;
if(count8>0)
cout<< "8" << " " << count8 << endl;
if(count9>0)
cout<< "9" << " " << count9 << endl;

return 0 ;
}

Simple Problem? Blind Author cant see?

LeighRogers14-Mar-07 11:50

LeighRogers

14-Mar-07 11:50

Hello all,
small problem with a simple app.

Its a simple Mp3 player app (simultation only). I have an MP3 Class that appears to load fine. It crashes out when I call the PrintMP3Details() function in Mp3.h. I get part of the output ie:
I'd really appreciate any help that anyone could provide - I've asked my lecturer four times over the past 7 days and he hasn't even replied... Sniff | :^)

Thanks in advance - Much appreciated.

"
Track 0 Contains:
Artist : BOMBS OUT HERE.....
"

MP3Player.Cpp

#include <fstream><br />
#include <iostream><br />
#include "mp3.h"<br />
<br />
using namespace std;<br />
int main (void)<br />
{<br />
    int length, count, iNo, menu, loop;<br />
    char str[80], fil[80], track[80], artist[80];<br />
    count = 0;<br />
    string filename;<br />
    cout << "Welcome to the MP3 player" << endl;<br />
    cout << "please enter filename (playlist.txt is default)" << endl;<br />
cin >> fil;                                                                     //Stores filename<br />
ifstream in(fil);                                                               //Opens file<br />
if(!in)                                                                         //if File cannot open<br />
{ <br />
cout << "Cannot open file.\n" << endl; <br />
} <br />
while(!in.eof())                                                                // While not end of file...<br />
{<br />
  in >> artist;                                                                 //Store first item as artist<br />
  in >> track;                                                                  //Store second item as track<br />
  in >> length;                                                                 //Store third item as length<br />
  count++;                                                                      <br />
} <br />
cout << endl;<br />
iNo=count;                                                                      //Copy total no. of records to iNO.<br />
<br />
cout << endl <<"File contains " << count << " files." << endl;                  //Print no. of records in file<br />
  in.close();                                                                   //Close file.<br />
Mp3 *Playlist[iNo];                                                             //Create pointer array of size iNO.<br />
//in.open();                                                                    //Open file<br />
count = 0;                                                                      //Reset Counter<br />
ifstream in2(fil);                                                              //Opens file<br />
if(!in)                                                                         //if File cannot open<br />
{ <br />
cout << "Cannot open file.\n" << endl; <br />
} <br />
cout << "marker " << endl;<br />
while(!in.eof())          <br />
{<br />
  in2 >> artist;                                                                //Store first item as artist<br />
  in2 >> track;                                                                 //Store second item as track<br />
  in2 >> length;                                                                //Store third item as length<br />
  count++;            <br />
  Playlist[count] = new Mp3(artist, track, length);    <br />
  cout << count << " contains " << artist << track << length << endl;                                                      <br />
} <br />
cout << endl;<br />
in.close();<br />
  <br />
  <br />
  <br />
  <br />
  while (menu !=0){<br />
     cout << "Please select from the following..." << endl<br />
     << "1) Print playlist (currently loaded)" << endl<br />
     << "0) Close MP3 player " <<endl << endl;<br />
     cin >> menu;<br />
     cout << endl;       <br />
  <br />
  switch (menu)<br />
{<br />
case 1:<br />
    for (int loop=0; loop<iNo;loop++)<br />
{<br />
//    Portfolio[iAC]->PrintAccountDetails();<br />
    cout << "Track " << loop << " Contains : " << endl;<br />
    Playlist[loop]->PrintMP3Details();<br />
    cout << endl << endl;<br />
}<br />
break;<br />
  <br />
case 2:<br />
     break;<br />
     return 0; <br />
}//End switch<br />
}//End While<br />
}//End of main<br />

MP3.h

<br />
    #include <fstream><br />
    #include <iostream><br />
    using namespace std;<br />
    <br />
    class Mp3<br />
    {   <br />
    private<br />
    :<br />
// Attributes...................................................................<br />
            string Artist;<br />
            string Track;<br />
            int Length;<br />
    <br />
    public:<br />
           <br />
//Constructor...................................................................<br />
    Mp3::Mp3(string Nartist, string Ntrack, int Nlength)<br />
    {<br />
    Artist = Nartist;<br />
    Track = Ntrack;<br />
    Length = Nlength;             <br />
    }<br />
    <br />
// Methods......................................................................<br />
// Gets.........................................................................<br />
    string GetArtist()const           {return Artist;}<br />
    string GetTrack()const            {return Track;}<br />
    int GetLength()const              {return Length;}<br />
    <br />
// Sets.........................................................................<br />
    void SetArtist (string strArtist) {Artist = strArtist;}<br />
    void SetTrack  (string strTrack)  {Track = strTrack;}<br />
    void SetLength (int    iLength)   {Length = iLength;}<br />
    <br />
//Functions.....................................................................<br />
      void PrintMP3Details() <br />
    {<br />
cout  << "Artist                   : " << Artist << endl<br />
      << "Track                    : " << Track  << endl<br />
      << "Length                   : " << Length << endl;<br />
    }<br />
    }; // end of Account class<br />

Re: Simple Problem? Blind Author cant see?

John R. Shaw14-Mar-07 15:33

John R. Shaw

14-Mar-07 15:33

I think the problem is the following:

count++; // WRONG!
Playlist[count] = new Mp3(artist, track, length);

Try this:

Playlist[count] = new Mp3(artist, track, length);
count++;

Or this:

Playlist[count++] = new Mp3(artist, track, length);

The first is wrong because you start by filling in Playlist[1] instead of PlayList[0]. Also at the end you will be filling in slot Playlise[iNo], which does not exist. As a further check in your loop, you may what to use while( !in.eof() && count < iNo ) as additional safety; although the way it is written now, that will not help.

The actual cause of an error is not always reported when it occurs, so remember to work backwards from the error (what happen before it).

P.S. Prefer ++count to count++, because if those operators are ever overload the difference will give you headaches.

INTP
"Program testing can be used to show the presence of bugs, but never to show their absence."Edsger Dijkstra

Re: Simple Problem? Blind Author cant see?

Hamid_RT14-Mar-07 19:15

Hamid_RT

14-Mar-07 19:15

If you want to play mp3 files you can also use of MCI functions.

WhiteSky

Need help communicating with MFC dialog boxes (domodal) [modified]

CoffeeAddict1914-Mar-07 11:10

CoffeeAddict19

14-Mar-07 11:10

Basically what I am trying to do is have two text strings pop in text boxes (CEdit) for the user when they open a dialog box. The problem is that when you call domodal, all control transfers to the dialog box, so everything has to be done before the call. In the past I have just set a flag in the dialog box class to let it know that something needs to be loaded, and placed the information there beforehand, and then called domodal. OnInitDialog gets called when the dialog pops up, checks for the flag, and loads whatever. It seems kind of messy though. Is there another more elegant way to do it? Is there some way I can modify DoModal to accept arguments?

Re: Need help communicating with MFC dialog boxes (domodal)

toxcct14-Mar-07 11:23

toxcct

14-Mar-07 11:23

have you seen This[^] article ?

[VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

Re: Need help communicating with MFC dialog boxes (domodal)

andersod214-Mar-07 12:27

andersod2

14-Mar-07 12:27

Along these same lines, do you know how to put carriage returns into the CEdit? Yeah, I know, noob question, but I haven't worked much with CStrings and CEdit controls, and I just realized that putting a "\n" into a char buffer then converting it to a CString won't work in a CEdit...how do I do this?

Re: Need help communicating with MFC dialog boxes (domodal) [modified]

CoffeeAddict1914-Mar-07 18:24

CoffeeAddict19

14-Mar-07 18:24

~~I think you have to use "\r \r".~~

Edit...sorry that's wrong here...it's "\r\n".

http://microsoft.ease.lsoft.com/scripts/wa-msn.exe?A2=ind9709a&L=mfc&T=0&P=10710[^]

-- modified at 0:29 Thursday 15th March, 2007

Re: Need help communicating with MFC dialog boxes (domodal)

andersod214-Mar-07 18:42

andersod2

14-Mar-07 18:42

that did the trick...thanks...seems counterintuitive, like I was programming for unix or something...I never even would have guessed that in a million years...

Re: Need help communicating with MFC dialog boxes (domodal)

andersod214-Mar-07 13:13

andersod2

14-Mar-07 13:13

Also, a totally unrelated way of doing this, but may be of use if you're using a DLL, is to create a shared data segment with #pragam data_seg() and put in a global variable in there which will keep track of the number of instances of subscribers to the DLL. Of course your program will have to import the DLL etc, which is not preferable at all, but like I said if you're already using a DLL it's another option.

Re: Need help communicating with MFC dialog boxes (domodal)

toxcct14-Mar-07 22:07

toxcct

14-Mar-07 22:07

globals are most of the time bad, and can be avoided using OOP data members.

[VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

Re: Need help communicating with MFC dialog boxes (domodal)

andersod215-Mar-07 10:30

andersod2

15-Mar-07 10:30

I made that post in the wrong thread...my bad

passing function pointer

ScotDolan14-Mar-07 10:53

ScotDolan

14-Mar-07 10:53

Right now, We have a ClxThreadClass that provides the capablity to create single worker thread for the class that inherits it. The function below shows the class member function that creates and starts the new thread. The desire worker code reside in _ThreadFunc.

<br />
<br />
The Current working design<br />
/*************************************************/<br />
bool ClxThreadClass::CreateNewThread()<br />
{<br />
     if( m_hThread == NULL )<br />
     {<br />
	// _beginthreadex(Security attributes, stack, Thread proc, Thread param, creation mode, Thread ID)<br />
	m_hThread = (HANDLE)_beginthreadex(NULL,   0,_ThreadFunc, this, CREATE_SUSPENDED, &uiThreadId);	<br />
        //<br />
	if ( NULL != m_hThread)<br />
	{<br />
		//SetThreadPriority(hThread, THREAD_PRIORITY_HIGHEST);<br />
        	ResumeThread( m_hThread );<br />
		m_bActive = true;<br />
		return true;<br />
	}else{<br />
		m_bActive = false;<br />
	}<br />
    }<br />
<br />
   return true;<br />
}<br />

However, We sometimes would like to use different function other than _ThreadFunc. How can we overload CreateNewThread member function to take an external and pass to beginthreadex. This external obect is not a member function of base or inherited class.

<br />
bool ClxThreadClass::CreateNewThread( void *ptr )<br />
{<br />
<br />
    if( m_hThread == NULL )<br />
    {<br />
	// _beginthreadex(Security attributes, stack, Thread proc, Thread param, creation mode, read ID)<br />
	m_hThread = (HANDLE)_beginthreadex(NULL,   0,	ptr, this, CREATE_SUSPENDED, &uiThreadId);	<br />
        //<br />
	if ( NULL != m_hThread)<br />
	{<br />
        	//SetThreadPriority(hThread, THREAD_PRIORITY_HIGHEST);<br />
		ResumeThread( m_hThread );<br />
		m_bActive = true;<br />
		return true;<br />
	}else{<br />
		m_bActive = false;<br />
	}<br />
    }<br />
    return true;<br />
<br />
}<br />

Scott Dolan
Jernie Corporation
Engineering & Manufacturing
Software, Hardware, & Enclosures

Re: passing function pointer

Mark Salsbery14-Mar-07 11:42

Mark Salsbery

14-Mar-07 11:42

Maybe something like this:

typedef unsigned (__stdcall *PTHREADFUNC)(void *);
...
bool ClxThreadClass::CreateNewThread(PTHREADFUNC pThreadFunc)
{
if( m_hThread == NULL )
{
   // _beginthreadex(Security attributes, stack, Thread proc, Thread param, creation mode, read ID)
   m_hThread = (HANDLE)_beginthreadex(NULL, 0, pThreadFunc, this, CREATE_SUSPENDED, &uiThreadId); 
 
   ...
 
}

"Great job, team. Head back to base for debriefing and cocktails."
(Spottswoode "Team America")

Re: passing function pointer

ThatsAlok14-Mar-07 19:34

ThatsAlok

14-Mar-07 19:34

Mark Salsbery wrote:
typedef unsigned (__stdcall *PTHREADFUNC)(void *);

if this function points to global function, it will work .. if it point to class member function.. then there would be some trouble.. i.e. we have to change the Funtion ptr declaration and pass the pointer of the class to that function!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
Global Interface Table: An Easy Way to Marshal an Interface Pointer[new]
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

Re: passing function pointer

Mark Salsbery14-Mar-07 20:13

Mark Salsbery

14-Mar-07 20:13

Right. The OP stated "This external obect is not a member function of base or inherited class"
which ~~sounded~~read like it wasn't a class method to me.

Mark

"Great job, team. Head back to base for debriefing and cocktails."
(Spottswoode "Team America")

Re: passing function pointer

ThatsAlok14-Mar-07 20:20

ThatsAlok

14-Mar-07 20:20

Mark Salsbery wrote:
he OP stated "This external obect is not a member function of base or inherited class"
which soundedread like it wasn't a class method to me.

oops my mistake.. it seems work is taking over me [ Smile | :)

]

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
Global Interface Table: An Easy Way to Marshal an Interface Pointer[new]
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

Get users names list

Caos00014-Mar-07 9:59

Caos000

14-Mar-07 9:59

Hi,
Can someone help me?
Im just trying to get a list of all windows users names in a local computer.

GetUserName gives us just the current user:

BOOL GetUserName(
LPTSTR lpBuffer,
LPDWORD lpnSize
);

but I dont know D'Oh! | :doh:

how can I get all the other users in the same machine.
Thanks.

Re: Get users names list

Mark Salsbery14-Mar-07 10:32

Mark Salsbery

14-Mar-07 10:32

Maybe this link will help - Users in Active Directory Domain Services[^]

I chose this link since it also has links to an "old" way to enumerate users Smile | :)

Mark

"Great job, team. Head back to base for debriefing and cocktails."
(Spottswoode "Team America")

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