[C++] Call a pushbutton and a LineEdit

SGaist

Hi,

Did you properly initialize it before trying to access it ?

Cervo2paille

@SGaist Thanks for your answer.
This is the question of my post : how to initialize them when they exist in my UI ?
Thanks

SGaist

If you created the widget with the Qt Creator wizard, it should already be done. Otherwise, the Designer document contains an example.

Cervo2paille

@SGaist said in [C++] Call a pushbutton and a LineEdit:

Otherwise

Thanks but i don't find in this documentation what i'm looking for.
I already put a screenshot of what i did : i created my buttons and my LineEdit in my file.ui.

Now i want to use them in my file.cpp, in my connect, but my buttons "are not declared in this scope".

Someone can help me to initialize them ?
Thanks

SGaist

The code you posted is incomplete so we can only guess what is happening.

Cervo2paille

@SGaist See all of my code :

ajouterproduit.cpp :

#include "ajouterproduit.h"
#include "ui_ajouterproduit.h"
#include "compteur.h"
#include "compteur.cpp"

ajouterproduit::ajouterproduit(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::ajouterproduit)
{
    ui->setupUi(this);
    setup();
}

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

void ajouterproduit::setup(){

    QString quantite = ui->quantite->text();
    ui->pushButtonPlus;
    quantite.setNum(compteur_.getQuantite());


    connect(pushButtonPlus, SIGNAL(clicked()), this, SLOT(incrementerQuantite));
    connect(pushButtonLess, SIGNAL(clicked()), this, SLOT(decrementerQuantite));
    connect(&compteur_, SIGNAL(envoyerQuantite(int)), quantite, SLOT(setNum(int)));
}

void ajouterproduit::incrementerQuantite(){
    compteur_.augmenterQuantite();
}
void ajouterproduit::decrementerQuantite(){
   compteur_.reduireQuantite();
}

void ajouterproduit::on_pushButton_3_clicked()

ajouterproduit.h :

#ifndef AJOUTERPRODUIT_H
#define AJOUTERPRODUIT_H

#include "compteur.h"
#include <QDialog>

namespace Ui {
class ajouterproduit;
}

class ajouterproduit : public QDialog
{
    Q_OBJECT

public:
    explicit ajouterproduit(QWidget *parent = nullptr);
    ~ajouterproduit();

    void setup();

public slots:
    void incrementerQuantite();
    void decrementerQuantite();

private slots:
    void on_pushButton_3_clicked();

    void on_pushButton_clicked();

private:
    Ui::ajouterproduit *ui;

    compteur compteur_;
};

#endif // AJOUTERPRODUIT_H

Thanks for advance

SGaist

@Cervo2paille said in [C++] Call a pushbutton and a LineEdit:

void ajouterproduit::setup(){
QString quantite = ui->quantite->text();
ui->pushButtonPlus;

The line above does nothing.

quantite.setNum(compteur_.getQuantite());


connect(pushButtonPlus, SIGNAL(clicked()), this, SLOT(incrementerQuantite));
connect(pushButtonLess, SIGNAL(clicked()), this, SLOT(decrementerQuantite));

ui-> is missing.

mpergand

@Cervo2paille said in [C++] Call a pushbutton and a LineEdit:

connect(&compteur_, SIGNAL(envoyerQuantite(int)), quantite, SLOT(setNum(int)));

Je prévois un autre problème :)

JonB

@Cervo2paille said in [C++] Call a pushbutton and a LineEdit:

connect(pushButtonPlus, SIGNAL(clicked()), this, SLOT(incrementerQuantite));
connect(pushButtonLess, SIGNAL(clicked()), this, SLOT(decrementerQuantite));

I don't think your SLOT(...)s are correct, when you get that far.

Cervo2paille

@SGaist said in [C++] Call a pushbutton and a LineEdit:

ui->pushButtonPlus;

I try to get my button ! If I do a mistake can you give me the correct code to call my button ? Thanks

@mpergand En effet j'ai aussi ce problème ci : "quantite" est une QString et pas Qobject donc ça pose problème. Comment procéder ? Merci

@JonB Oh thanks in fact :

connect(pushButtonPlus, SIGNAL(clicked()), this, SLOT(incrementerQuantite()));
connect(pushButtonLess, SIGNAL(clicked()), this, SLOT(decrementerQuantite()));

If you need to test my project, see here :
http://e.pc.cd/bcMotalK
Thanks.

jsulm

@Cervo2paille said in [C++] Call a pushbutton and a LineEdit:

If I do a mistake can you give me the correct code to call my button ?

All you have to do is to add ui-> to pushButtonPlus as @SGaist already told you:

connect(ui->pushButtonPlus, SIGNAL(clicked()), this, SLOT(incrementerQuantite()));

And you really should switch to newer Qt5 connect syntax: https://doc.qt.io/qt-6/signalsandslots.html

Cervo2paille

@jsulm thanks between the answers and you message, this is what i understand after few minutes :D
I understand but the documentation never show how to call and UI button by using ui->. :S

My last problem concerns this line :

    connect(&compteur_, SIGNAL(envoyerQuantite(int)), quantite, SLOT(setNum(int)));

Sans titre.png
Thanks

jsulm

@Cervo2paille If you read the error message you should know what the problem is: the third parameter is a QString, so quantite is a QString, right? That can't work.
And again: please use new connect syntax...

Cervo2paille

Ok i understand :

    connect(&compteur_, SIGNAL(envoyerQuantite(int)), ui->quantite, SLOT(setNum(int)));

I got again an error on this line :

But this is a classic class :

Thanks for advance.

PS : don't anwer i'm looking for

JonB

@Cervo2paille
Looks like compteur_ (the compteur class) is not a QObject, and you can only use QObjects for signals or slots.

Cervo2paille

In fact it was a simple class
I put it in QObjet :

#ifndef COMPTEUR_H
#define COMPTEUR_H

#include <QObject>

class compteur: public QObject
{
       Q_OBJECT
public:
    compteur();
    int getQuantite();
    void augmenterQuantite();
    void reduireQuantite();

signals:
    int envoyerQuantite(int);

private:
    int quantite_;
};

#endif // COMPTEUR_H

But i got many error in my compteur.cpp :

"Multiple definition of compteur". I clean, recompilate my project...
Any idea? Thanks

jsulm

@Cervo2paille said in [C++] Call a pushbutton and a LineEdit:

I clean

Did you also try to delete the build folder?

Please post the error messages as text, not images...

Cervo2paille

@jsulm yes i did, but nothing change.

My compteur.cpp :

#include "compteur.h"

compteur::compteur():quantite_(0)
{

}

int compteur::getQuantite(){
    return quantite_;
}
void compteur::augmenterQuantite(){
    quantite_++;
    emit envoyerQuantite(quantite_);
}
void compteur::reduireQuantite(){
    quantite_--;
    emit envoyerQuantite(quantite_);
}

Thanks

JonB

@Cervo2paille
I do not know whether it would cause the error messages you see, but where does your compteur() constructor call the base QObject constructor?

Cervo2paille

@JonB Sorry i don't understand your question.
I got the filling that put my class like a ": public QObject" was enough.

If you need more information see my compteur.h :

#ifndef COMPTEUR_H
#define COMPTEUR_H

#include <QObject>

class compteur: public QObject
{
       Q_OBJECT
public:
    compteur();
    int getQuantite();
    void augmenterQuantite();
    void reduireQuantite();

signals:
    int envoyerQuantite(int);

private:
    int quantite_;
};

#endif // COMPTEUR_H

Thanks