No such slot ?



  • Hey guys , sorry for asking lots of questions first :(

    second , I just finished my midterms " finally " :D , and I wanted to make a little calculator " I'm new so please don't get mad at me :D "

    so first I used a class that I used before to to convert to int " the line edit string " , so I added a button and a new line edit which is read only , and I wanted it to display x+y when the user clicks " compute " , the problem is it says no such slot for get_sum() and when I press compute after putting two numbers it doesn't show the answer.

    here's the header:

    @
    #ifndef CHECKCLASS_H
    #define CHECKCLASS_H
    #include<QLabel>
    #include<QHBoxLayout>
    #include<QLineEdit>
    #include<QIntValidator>
    #include<QWidget>
    #include<QPushButton>
    class checkclass : public QWidget
    {
    Q_OBJECT
    public:
    checkclass(QWidget *parent=0);

    private slots:

    void convert();
        void convert1();
        void get_sum();
    private:
        QPushButton *ReturnV;
        QLineEdit *edit;
        QLineEdit *edit1;
        QLineEdit *E;
    QIntValidator *Valid;
        QHBoxLayout *left;
    
        QHBoxLayout *Main;
    
        int x;
        int y;
    

    };

    #endif // CHECKCLASS_H
    @

    here's the imp:

    @
    #include "checkclass.h"

    checkclass::checkclass(QWidget *parent):
    QWidget(){
    Valid=new QIntValidator;
    edit = new QLineEdit;
    edit1=new QLineEdit;
    E=new QLineEdit;
    ReturnV=new QPushButton;
    ReturnV->setText("Compute");
    E->setReadOnly(true);

         left= new QHBoxLayout;
         Main=new QHBoxLayout;
            edit->setMaximumWidth(20);
            edit->setFixedWidth(20);
            edit->setValidator(Valid);
            edit1->setMaximumWidth(20);
            edit1->setFixedWidth(20);
            edit1->setValidator(Valid);
    
            QObject:: connect(edit,SIGNAL(editingFinished()),this,SLOT(convert()));
                   QObject:: connect(edit1,SIGNAL(editingFinished()),this,SLOT(convert1()));
                   QObject::connect(ReturnV,SIGNAL(clicked()),E,SLOT(get_sum()));
            left->addWidget(edit);
    
            left->addWidget(edit1);
            left->addWidget(E);
            left->addWidget(ReturnV);
            Main->addLayout(left);
    
    
            setLayout(Main);
    

    }

    void checkclass::convert(){
    QString numbertext=edit->text();
    x=numbertext.toInt();

    }
    void checkclass::convert1(){
    QString numbertext=edit1->text();
    y=numbertext.toInt();

    }
    void checkclass::get_sum(){
    int z=x+y;
    QString textN= QString::number(z);
    E->setText(textN);

    }
    @

    Thanks in advance.



  • Hi, this line:
    QObject::connect(ReturnV,SIGNAL(clicked()),E,SLOT(get_sum()));
    try change E to this:
    QObject::connect(ReturnV,SIGNAL(clicked()),this,SLOT(get_sum()));



  • Ah man thanks it worked , but could you explain why my way didn't work ? please :(



  • Well, it could, but then you have to check, if the E class also has a
    slot: void get_sum() declared?



  • Ah , thank you ^^


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