Refresh QLCDNumber

martial123

Hi ,
I have a probleme with a QLCDNumber.
When i want to refresh is value with connect in other class, nothing is appening...
also I want to incremented his value too but i don't know how i can do that .. (like, each passage in the slot, display(value ++) )

this is my slot who receive signal :

void Window018703::set_lcdNumber_seatUp(int a)
{
    int B = 1;
    ui->lcdNumber_seatUp->display(B);
}

class who call slot on push on button :

#include "window018704.h"
#include "ui_window018704.h"
#include <iostream>
 
using namespace std;
 
Window018704::Window018704(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Window018704)
{
    ui->setupUi(this);
    cout << " classe 704 ... " <<  endl;
 
   Window018703 *window018703 = new Window018703();
   QObject::connect(ui->pushButton_018704, &QPushButton::clicked , window018703, &Window018703::set_lcdNumber_seatUp);
 
}
 
Window018704::~Window018704()
{
    delete ui;
}
 
void Window018704::windowView()
{
    this->show();
}

class who countain slot receiver :

#include "window018703.h"
#include "ui_window018703.h"
#include <iostream>
 
//#define  B 1
using namespace std;
Window018703::Window018703(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Window018703)
{
    ui->setupUi(this);
    //int a =5;
    cout << " nous somme avant l'appuis " <<  endl;
 
    QObject::connect(ui->pushButton, &QPushButton::clicked, this, &Window018703::set_lcdNumber_seatUp);
    cout << " nous somme apres l'appuis " <<  endl;
 
}
 
Window018703::~Window018703()
{
    delete ui;
}
 
void Window018703::windowView()
 
{
    this->show();
}
 
void Window018703::set_lcdNumber_seatUp(int a)
{
    int B = 1;
    cout << " önt rentre ici et a vaut = " << B << endl;
    ui->lcdNumber_seatUp->display(B);
}

Thank you for your help
Martial

mrjj

Hi
One thing.
Button click do not have parameter but you slot has
QObject::connect(ui->pushButton_018704, &QPushButton::clicked , window018703, &Window018703::set_lcdNumber_seatUp);

void Window018703::set_lcdNumber_seatUp(int a) <<< int a is not valid
{
    int B = 1;
    cout << " önt rentre ici et a vaut = " << B << endl;
    ui->lcdNumber_seatUp->display(B);
}

also I want to incremented his value too but i don't know how i can do that .. (like, each passage in the slot, display(value ++) )

One option is to do

void Window018703::set_lcdNumber_seatUp()
{
 static   int B = 1;
    cout << " önt rentre ici et a vaut = " << B << endl;
    ui->lcdNumber_seatUp->display(B++);
}

that would keep raising B on each call till program ends.

martial123

@mrjj

Thank you for your response, the increment work well when the connect and slot are in the same class, when I try to call this slot by an other class, this doesn't work ...

mrjj

@martial123
It should work the same.
Are you sure its the right one, you are looking at ?
Yo create a new window here
Window018703 *window018703 = new Window018703(); <<< new window
QObject::connect(ui->pushButton_018704, &QPushButton::clicked , window018703, &Window018703::set_lcdNumber_seatUp);
but you dont seem to show it so i wonder if you already made one somewhere else
and are looking at that ?

martial123

@mrjj

You are right ...
I created a new instance but never show him with instance.show()
because the window is already open and the instance has already been created ... so I should get this instance and call the connect on it. but how to do that?

my window are open like this before push to connect slot display() :

#include "window018703.h"
#include "ui_window018703.h"
#include <iostream>

//#define  B 1
using namespace std;
Window018703::Window018703(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Window018703)
{
    ui->setupUi(this);
    //int a =5;
    cout << " nous somme avant l'appuis " <<  endl;

    QObject::connect(ui->pushButton, &QPushButton::clicked, this, &Window018703::set_lcdNumber_seatUp);
    cout << " nous somme apres l'appuis " <<  endl;

}

Window018703::~Window018703()
{
    delete ui;
}

void Window018703::windowView()

{
    this->show();
}

void Window018703::set_lcdNumber_seatUp()
{
    static int B = 0;
    cout << " önt rentre ici et a vaut = " << B << endl;
    ui->lcdNumber_seatUp->display(B++);
}

i think in windows018704 class , I have to recover this instance? :


void Window018703::windowView()

{
    this->show();
}

this is a slot who call by an other class when users are finished to fill in all entries...

mrjj

Hi
But where do you create the first instance?
Could you not connect it to the other window there?

martial123

@mrjj

in fact, my program are composed by 3 classe :

a graphical class is used by users to fill fields
when all fieds are filled,
this class sets off this slot with this connect :

        if(this->get_m_boxGGI() == 18703)
        {
            Window018703 *window018703 = new Window018703();
            QObject::connect(ui->pushButtonOk, &QPushButton::clicked , window018703, &Window018703::windowView);

        }

the slot :

void Window018703::windowView()

{
    this->show();
}

so after that, first class is hide() and the second class is show with this->show.
then, the third class countain juste 1 button ( for example,
because later it's a reception on the serial port that will declancher the incrementation of the QLCDNumber) to connect with slot who increment display ...

so the second window is already open , so i need to recover the first instance that served to show him but i don't know how ...

if i do that :

void Window018703::set_lcdNumber_seatUp()
{
    static int B = 0;
    cout << " önt rentre ici et a vaut = " << B << endl;
    this->show();
    ui->lcdNumber_seatUp->display(B++);
}

Window018703 redisplay and after that , it work ..
but normally, window are already open so that's not quite what I want

it is clearer ?
Thanks a lot ...

mrjj

Hi
So is
if(this->get_m_boxGGI() == 18703)
{
Window018703 *window018703 = new Window018703(); << the real instance ?
QObject::connect(ui->pushButtonOk, &QPushButton::clicked , window018703, &Window018703::windowView);

the only one ?
also then its the THIRD class that needs to talk to Window018703 ?

martial123

@mrjj

unless I'm wrong but yes it's the first instance
and

yes the third class talk to increment display ...

the first class is hide because it just serves in start to fill variables especially : m_boxGGI ...

mrjj

Hi
ok.
Where is the code ?
if(this->get_m_boxGGI() == 18703)
{...
is that in first window ?
So if you store
Window018703 *window018703 as a member, you can use it later to connect
when you open the third one?

martial123

@mrjj yes the code is in the first class ( first window)

how i can store in in membre ??

mrjj

@martial123
and from first window, you also open the third one ? correct?
To make it memeber.
simply put
Window018703 *window018703 = nullptr; in first window.h inside class
like

class MainWindow : public QMainWindow
{
    Q_OBJECT
......
private:
    Ui::MainWindow *ui;
  Window018703 *window018703 = nullptr;  // also include the #include "Window018703.H" in top of file
};

and then change code here

if(this->get_m_boxGGI() == 18703)
{
window018703 = new Window018703(); << use the one from .h
QObject::connect(ui->pushButtonOk, &QPushButton::clicked , window018703, &Window018703::windowView);

Then later the variable in .h (window018703 ) points to the instance.

martial123

@mrjj

in fact, it is the main who show the third window but its not importante,

i did what you told me , but i can not to catch my instance ( or member ...) like this with get methode to call him in the third classe :

in first window .cpp :

Window018703* get_window018703()
{
    return window018703;
    
}

.h :

        Window018703* get_window018703();

he tell me an error :
use of undeclared identifier 'window018703'

mrjj

Hi
Well then maybe you can connect in main ?
You really need access to the instance and there is no magical way to get it.
So if main know all 3 windows, you can connect there ?

martial123

@mrjj
the instance is created when i do that no ? :

if(this->get_m_boxGGI() == 18703)
       {
           window018703 = new Window018703();

           QObject::connect(ui->pushButtonOk, &QPushButton::clicked , window018703, &Window018703::windowView);

       }

mrjj

@martial123
Yes but you need that window018703 variable in third form.
And third form is created in main ?

martial123

@mrjj
yes my main show first and third window ... :

#include <QApplication>
#include <QtWidgets>
#include <QLabel>

#include "window1.h"
#include "window018703.h"
#include "window018704.h"


using namespace std;
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
       window1 window1;
       window1.show();

       Window018704 window2;
       window2.show();
  
    return app.exec();
}

mrjj

@martial123

So connect it all up there?
Im getting a bit confused with the names, so not sure if 04 has 03 or reverse.


     window1 window1;
     window1.show(); << this has window018703 ?

     Window018704 window2;
     connect( window1.get_window018703(), xxxx )
       
       window2.show();

martial123

@mrjj

No ^^

i have 3 classes :

first : window1
second: Window018703
third : Window018704 ...

mrjj

@martial123
well you need one place where you have the instance you want to connect.
I not sure where Window018703 comes to life, but cant you call the get_window018703()
on it from main to get the instance.
It must be in window1 or window2 ? (variables)