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How to Send Data from One Ui to Another



  • Hi,

    I have one MainWindow and one Class; I want to send data between them using custom signal and slot. I can't seem to figure it out, I need help.

    Here is my code:
    MainWindow.h

    #ifndef MAINWINDOW_H
    #define MAINWINDOW_H
    
    #include <QMainWindow>
    #include <iostream>
    #include "receive.h"
    QT_BEGIN_NAMESPACE
    namespace Ui { class MainWindow; }
    QT_END_NAMESPACE
    
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
    
    public:
        MainWindow(QWidget *parent = nullptr);
        ~MainWindow();
    signals:
        void sendit(QString name);
    private slots:
        void on_send_button_clicked();
        void display(QString e)
        {        
         std::cout<<"Here is where I am called this "<<e.toStdString()<<std::endl;
        }
    
    private:
        Ui::MainWindow *ui;
       
    };
    #endif // MAINWINDOW_H
    

    MainWindow.cpp

    #include "mainwindow.h"
    #include "ui_mainwindow.h"
    #include "receive.h"
    
    MainWindow::MainWindow(QWidget *parent)
        : QMainWindow(parent)
        , ui(new Ui::MainWindow)
    {
        ui->setupUi(this);    
       Receive *r = new Receive();
       connect(this, SIGNAL(sendit(QString)), r, SLOT(display(QString)));
    
    }
    
    MainWindow::~MainWindow()
    {
        delete ui;
    }
    
    
    void MainWindow::on_send_button_clicked()
    {
        emit sendit(ui->lineEdit->text());
    
    }
    

    receive.h

    #ifndef RECEIVE_H
    #define RECEIVE_H
    
    #include <iostream>
    #include <QDialog>
    
    class Receive : public QDialog
    {
    public:
        Receive();
    private slots:
        void display(QString e);
    };
    
    #endif // RECEIVE_H
    

    receive.cpp

    #include "receive.h"
    #include "mainwindow.h"
    
    Receive::Receive()
    {
        
    }
    
    void Receive::display(QString e)
    {    
     std::cout<<"Here is where I am called this "<<e.toStdString()<<std::endl;
    }
    

    When I run this program, I get this message:

    06:26:29: Starting C:\Users\Troy\Documents\build-tests-Desktop_Qt_5_14_1_MinGW_32_bit-Debug\tests.exe ...
    QObject::connect: No such slot QDialog::display(QString) in ..\tests\mainwindow.cpp:11
    QObject::connect: (sender name: 'MainWindow')

    How do I get this done, please?

    Thank you for your help.


  • Qt Champions 2019

    @delivite Make your slot public, not private


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