C / C++ / MFC

Re: DialogBox Create Fails

15-May-15 6:01

What type of object is Show_storage?

What does Create() return?

Where is your code called from, or what is it in response to?

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modified 15-May-15 15:59pm.

ForNow15-May-15 6:15

ForNow

15-May-15 6:15

A CDialog

Create never return it aborts causes an an exception

In the assert highlighted in bold

Re: DialogBox Create Fails

Richard MacCutchan15-May-15 22:25

Property Grid alignment issue with sub-group

15-May-15 22:25

The assert fails because the CWnd* does not point to an object that contains a valid Window handle. Something in your code has not been initiailised correctly, or you are calling Create from outside of a Window class. What class is Show_storage?

Maximilien15-May-15 4:16

Maximilien

15-May-15 4:16

I am creating a simple property grid (CMFCPropertyGridCtrl) containing sub groups (value list)

There is a alignment issue for the sub groups where the labels are drawn with a left offset (see in particular the "Level2" label)

Why is the "Level2" label not aligned the same was as the "Level1" label?
I would imagine that it should be aligned at the same level as the "subLevel1" label.

See screenshot : http://imgur.com/9JeC4iz

Here is how I code the property grid:

CMFCPropertyGridProperty* level1Group = new CMFCPropertyGridProperty(_T("Level1"), 0, TRUE );
CMFCPropertyGridProperty* subLevel1 = new CMFCPropertyGridProperty(_T("subLevel1"), _T("subLevel1"), _T("subLevel1") );
level1Group->AddSubItem(subLevel1);

CMFCPropertyGridProperty* level2Group = new CMFCPropertyGridProperty(_T("Level2"), 0, TRUE );
CMFCPropertyGridProperty* subLevel21 = new CMFCPropertyGridProperty(_T("SubLevel2.1"), _T("SubLevel2.1"), _T("SubLevel2.1") );
CMFCPropertyGridProperty* subLevel22= new CMFCPropertyGridProperty(_T("SubLevel2.2"), _T("SubLevel2.2"), _T("SubLevel2.2") );
CMFCPropertyGridProperty* subLevel23 = new CMFCPropertyGridProperty(_T("SubLevel2.3"), _T("SubLevel2.3"), _T("SubLevel2.3") );

level2Group->AddSubItem(subLevel21);
level2Group->AddSubItem(subLevel22);
level2Group->AddSubItem(subLevel23);
level1Group->AddSubItem(level2Group);
m_PropertyGrid.AddProperty(level1Group);

I tried inheriting my own CMFCPropertyGridProperty class and overwrite the OnDrawName but because of many protected members in the base class. (see CMFCPropertyGridProperty::OnDrawName in afxpropertygridctrl.cpp )

Now, I did overwrite the OnDrawName method, but removed lot of code that was in the base method that did not compile (access to protected members); but it seems to be OK.

Thanks.

Max.

I'd rather be phishing!

An analog switch, but more efficient

Vladimi_r215-May-15 4:15

Vladimi_r2

15-May-15 4:15

As is well known when using switch (expression), thus:
"The expression must be of an integral type or of a class type for which there is an unambiguous conversion to integral type".
If the switch contains a number of case / 2 to 4 /, then there is no problem.
Well, if you say case is 30 pieces, then dostura to 29 in a row case, the compiler must make 29 comparisons.
Below is a one of the solutions to this problem.

And so the program as expression must transmit the index number to any array, containing the address points
transition operator goto.
Everything!

Notes: Of course array must contain the called function.

modified 15-May-15 11:09am.

Re: An analog switch, but more efficient

jeron115-May-15 5:06

jeron1

15-May-15 5:06

Have a gander here[^]. Pay particular attention to #11.

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Calculating average in a high priority thread

Member 935023714-May-15 23:18

Member 9350237

14-May-15 23:18

Hi Guys!,

I'm developing a simple tracking game using two haptic devices as controllers.
Haptic rendering is executed in a high priority thread.
During the experiment, force experienced will depends on the position of each player, it's calculated as follows:

C++

coupledForce1 = cMul(Kp, (newPosition2-newPosition1))-(cMul(Kb, (linearVelocity1)));

C++

coupledForce2 = cMul(Kp, (newPosition1-newPosition2))-(cMul(Kb, (linearVelocity2)));

I have 100 trials of tracking tasks and I have to calculate the average interaction force during each trial. How it can be done? my issue is: this manipulation have to be done in a thread with execution rate of around 8KHz

Thanks!

Jochen Arndt14-May-15 23:27

Jochen Arndt

14-May-15 23:27

Please don't repost questions. You have already asked this here Calculating average in a thread[^].

Member 935023714-May-15 23:36

Member 9350237

14-May-15 23:36

my bad!, just removed

Jochen Arndt14-May-15 23:42

Jochen Arndt

14-May-15 23:42

Thank you. The problem with duplicate questions is that you may get answers from different users to both questions.

A clarification question to yours: Do you need code to calculate the average?
If so, you may search for "moving average" or "rolling average".

Member 935023715-May-15 0:19

Member 9350237

15-May-15 0:19

Thank you!. I have already seen some implementation of moving average. But I'm not sure about how to implement for my application. Since it's in a thread which is executing at 8Khz, I'm wondering how to store forces trial by trial and to take avareage?

Jochen Arndt15-May-15 0:53

Jochen Arndt

15-May-15 0:53

See this Stackoverflow thread: http://stackoverflow.com/questions/10990618/calculate-rolling-moving-average-in-c-or-c[^].

The fastest solution would be a ring buffer and a total sum variable (untested):

C++

int items = 0;
int ndx = 0;
int buffer[buffer_Size];
// May need floating point here when max. value * buffer_size >= INT_MAX
int sum = 0;

int get_av(int val)
{
    if (items >= buffer_size)
        sum -= buffer[ndx];
    else
        ++items;
    sum += val;
    buffer[ndx] = val;
    if (++ndx >= buffer_size)
        ndx = 0;
    return sum / items;
}

This should be fast enough for your requirements

Exception in code C

Member 1169244814-May-15 21:33

Member 11692448

14-May-15 21:33

Hello,
This is my code.
When i compile and execute it i have the following error:

1 [main] test 5952 exception::handle: Exception: STATUS_ACCESS_VIOLATION
    722 [main] test 5952 open_stackdumpfile: Dumping stack trace to test.exe.sta
ckdump

C++

#include <stdio.h>
#include<stdlib.h>
#include<string.h>

typedef struct Date{
int J ;
int M ;
int A ;
} Date;

typedef struct Operation{
char Obj[30];
float Mnt ;
Date Date_Tr ;
int Type_Tr ;
int Etat ;
} Operation;

typedef struct Cellule{
Operation Info ;
struct Cellule *succ ;
} Cellule ;

typedef Cellule * Liste ;

int EgaliteDates(Date d1 , Date d2)
{
    if ((d1.J==d2.J) && (d1.M==d2.M) && (d1.A==d2.A))
    return 0;
    else
    {
        if ((d1.A>d2.A) || ((d1.A==d2.A) && (d1.M>d2.M)) || (((d1.A==d2.A) && (d1.M==d2.A) && (d1.J==d2.J))))
            return 1;
        else
            return 2;
             }
}
Liste InsertionOperation(Liste L , Operation op)
{

		Liste temp;
		Liste pred;
		Liste element;
 		element = malloc(sizeof(Liste));
    	element->Info = op;
    	element->succ = NULL;

    	if(L == NULL)
    	{
			L=element;
    	}
    	else
    	{
        	if (EgaliteDates(L->Info.Date_Tr,op.Date_Tr)==2)
        	{
        		element->succ= L;
        		L=element;
			}
			else
			{
			temp=L;
			pred=L;
        	while((temp->succ != NULL) && (EgaliteDates(temp->Info.Date_Tr,op.Date_Tr)<2))
        	{
        		pred=temp;
            	temp = temp->succ;
        	}
        	element->succ=temp->succ;
        	pred->succ = element;

        	}
    	}
    	return L;
}

void afficherListe(Liste L)
{
    Cellule *tmp = L;
    int i=0;
    while(tmp != NULL)
    {
        i++;
        printf("Objet %d : %s, montant: %f, date : %d %d %d, type: %s\n", i,tmp->Info.Obj,tmp->Info.Mnt,tmp->Info.Date_Tr.J,tmp->Info.Date_Tr.M,tmp->Info.Date_Tr.M,tmp->Info.Type_Tr,tmp->Info.Etat);
        tmp = tmp->succ;
    }
}

void RechercheDate(Liste L, Date minDate , Date maxDate )
{
Cellule *tmp = L;
printf("liste des objets entre %d/%d/%d et %d/%d/%d: \n",minDate.J,minDate.M,minDate.A,maxDate.J,maxDate.M,maxDate.A);
    while(tmp != NULL)
    {
        if ((EgaliteDates(tmp->Info.Date_Tr , maxDate)<2) && (EgaliteDates(minDate,tmp->Info.Date_Tr)<2))
        printf("Objet : %s, montant: %f, date : %d %d %d, type: %s\n",tmp->Info.Obj,tmp->Info.Mnt,tmp->Info.Date_Tr.J,tmp->Info.Date_Tr.M,tmp->Info.Date_Tr.M,tmp->Info.Type_Tr,tmp->Info.Etat);
        tmp = tmp->succ;
    }
}

void ReglerOp(Liste en_cours , Liste reglee, char obj_op[])
{
Cellule *tmp = en_cours;
Cellule *pred = en_cours;
    while((tmp != NULL) && (strcmp(en_cours->Info.Obj,obj_op) != 0))
    {
        pred=tmp;
        tmp = tmp->succ;
    }
    if (tmp==en_cours)
    en_cours=en_cours->succ;
    else
        pred->succ=tmp->succ;
    tmp->Info.Etat=1;
    InsertionOperation(reglee , tmp->Info);
    free(tmp);
}

main()
{
    Date d1 = {2,10,2012};
    Date d2 = {2,12,2012};
    Date d3 = {12,10,2012};
    Date d4 = {10,12,2011};
    Date d5 = {2,10,2012};
    Date d6 = {2,10,2012};
    printf("Comapraison %d/%d/%d et %d/%d/%d donne %d\n",d1.J,d1.M,d1.A,d2.J,d2.M,d2.A,EgaliteDates(d1 , d2));
    printf("Comapraison %d/%d/%d et %d/%d/%d donne %d\n",d3.J,d3.M,d3.A,d4.J,d4.M,d4.A,EgaliteDates(d3 , d4));
    printf("Comapraison %d/%d/%d et %d/%d/%d donne %d\n",d5.J,d5.M,d5.A,d6.J,d6.M,d6.A,EgaliteDates(d5 , d6));
    Liste L;
    Operation op1= {"objet1",23.5,{30,3,2012},1,1};
    Operation op2= {"objet2",24.5,{2,2,2012},1,1};
    Operation op3= {"objet3",25.5,{12,4,2013},1,1};
    Operation op4= {"objet4",26.5,{15,10,2014},1,1};
    Operation op5= {"objet5",27.5,{9,8,2014},1,1};
    Operation op6= {"objet6",28.5,{10,11,2015},1,1};
    L=InsertionOperation(L , op1);
    L=InsertionOperation(L , op2);
    L=InsertionOperation(L , op3);
    L=InsertionOperation(L , op4);
    L=InsertionOperation(L , op5);
    L=InsertionOperation(L , op6);
    printf("\n liste réglée \n");
    afficherListe(L);
    Date dmin = {1,1,2014};
    Date dmax = {30,12,2015};
    RechercheDate(L,dmin,dmax);
    Liste en_cours;
    Operation ec1= {"ec1",20.5,{7,2,2012},2,0};
    Operation ec2= {"ec2",33.5,{30,3,2010},2,0};
    Operation ec3= {"ec3",43.5,{9,12,2014},2,0};
    Operation ec4= {"ec4",53.5,{10,10,2013},2,0};
    L=InsertionOperation(en_cours , ec1);
    L=InsertionOperation(en_cours, ec2);
    L=InsertionOperation(en_cours , ec3);
    L=InsertionOperation(en_cours , ec4);
    printf("\n liste en cours \n");
    afficherListe(en_cours);
    ReglerOp(en_cours , L, "ec4");
    ReglerOp(en_cours , L, "ec1");
    printf("\n liste réglée \n");
    afficherListe(L);
    printf("\n liste en cours \n");
    afficherListe(en_cours);

}

So what is wrong with my code and how can i fix it?
Thanks.

Richard MacCutchan14-May-15 22:35

14-May-15 22:35

You will need to use your debugger to find where the exception occurs, and update the question with that information.

Member 1169244814-May-15 22:59

Member 11692448

14-May-15 22:59

in line 54 i have (Liste InsertionOperation(Liste L , Operation op))
Program received signal SIGSEGV

modified 15-May-15 5:13am.

Richard MacCutchan15-May-15 2:53

15-May-15 2:53

Where exactly is line 54, and what are the values of the variables that are being referenced?

David Crow15-May-15 2:13

15-May-15 2:13

Single step through the code using the debugger.

Philippe Mori16-May-15 2:45

Philippe Mori

16-May-15 2:45

And test one function at a time for each case. Put breakpoint in each branch and ensure you test each one or better yet, make unit test for each one.

Philippe Mori

Copy Text from dialog box

Philippe Mori16-May-15 2:41

Philippe Mori

16-May-15 2:41

C++

element = malloc(sizeof(Liste));

should be

C++

element = malloc(sizeof(Cellule));

You are allocating 4 bytes (on 32 bit platform) instead of approximatively 60 bytes.

The following line is also incorrect:

C++

en_cours=en_cours->succ;

Since you are Inside a function, the pointer is passed by value and a change inside the function has no effect outside of it. You need to have a pointer to a pointer to be able to update the pointer at the caller location.

You don't initialized new list to NULL so first insertion might fails because the pointer is garbage.

Philippe Mori

Thakur JAI SINGH13-May-15 23:31

Thakur JAI SINGH

13-May-15 23:31

Hi ,

I am using a dialog box and there are some text in the dialog box and want to copy that text from the dialog box .

Just want to know how to do it.

Richard MacCutchan14-May-15 1:22

14-May-15 1:22

See https://msdn.microsoft.com/en-us/library/windows/desktop/ms645489%28v=vs.85%29.aspx[^]. It really makes life easier if you read the documentation for the controls you use.

David Crow14-May-15 4:04

14-May-15 4:04

Thakur JAI SINGH wrote:
I am using a dialog box...

So the dialog box is created and displayed via your code, or are you wanting to access a dialog box from some other app?

Thakur JAI SINGH wrote:
...and there are some text in the dialog box...

What type of control specifically?

Thakur JAI SINGH18-May-15 0:48

Thakur JAI SINGH

18-May-15 0:48

@DavidCroww

Dialog box is displayed via my code.

And there are lots of text on my dialog box and I have to copy the whole text available there on the dialog box.

David Crow18-May-15 2:21