Transfer variable from qmainwindow to qwidget

[weiweiqiao]

this is a sample for passing data from one dialog to dialog01.
In dialog: one qpushbutton, one qlienedit, in dialog01: qlineedit;

dialog.h

#ifndef DIALOG_H
#define DIALOG_H
 
#include <QDialog>
 
class Dialog01;
 
namespace Ui {
class Dialog;
}
 
class Dialog : public QDialog
{
    Q_OBJECT
 
public:
    explicit Dialog(QWidget *parent = 0);
    ~Dialog();
 
public slots:
    void sendText();
 
signals:
    void signalText(QString text);
 
private:
    Ui::Dialog *ui;
 
    Dialog01* pDialog;
};
 
#endif // DIALOG_H

#ifndef DIALOG_H
#define DIALOG_H

#include <QDialog>

class Dialog01;

namespace Ui {
class Dialog;
}

class Dialog : public QDialog
{
    Q_OBJECT

public:
    explicit Dialog(QWidget *parent = 0);
    ~Dialog();

public slots:
    void sendText();

signals:
    void signalText(QString text);

private:
    Ui::Dialog *ui;

    Dialog01* pDialog;
};

#endif // DIALOG_H

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dialog.cpp

#include "dialog.h"
#include "ui_dialog.h"
 
#include "dialog01.h"
 
Dialog::Dialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Dialog),
    pDialog(new Dialog01(this))
{
    ui->setupUi(this);
 
    connect(ui->pushButton, &QPushButton::clicked,
            this, &Dialog::sendText);
    connect(this, &Dialog::signalText,
            pDialog, &Dialog01::recvText);
}
 
Dialog::~Dialog()
{
    delete ui;
}
 
void Dialog::sendText()
{
    emit signalText(ui->lineEdit->text());
 
    pDialog->setVisible(true);
}

#include "dialog.h"
#include "ui_dialog.h"

#include "dialog01.h"

Dialog::Dialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Dialog),
    pDialog(new Dialog01(this))
{
    ui->setupUi(this);

    connect(ui->pushButton, &QPushButton::clicked,
            this, &Dialog::sendText);
    connect(this, &Dialog::signalText,
            pDialog, &Dialog01::recvText);
}

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

void Dialog::sendText()
{
    emit signalText(ui->lineEdit->text());

    pDialog->setVisible(true);
}

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dialog01.h

#ifndef DIALOG01_H
#define DIALOG01_H
 
#include <QDialog>
 
namespace Ui {
class Dialog01;
}
 
class Dialog01 : public QDialog
{
    Q_OBJECT
 
public:
    explicit Dialog01(QWidget *parent = 0);
    ~Dialog01();
 
public slots:
    void recvText(QString text);
 
private:
    Ui::Dialog01 *ui;
};
 
#endif // DIALOG01_H

#ifndef DIALOG01_H
#define DIALOG01_H

#include <QDialog>

namespace Ui {
class Dialog01;
}

class Dialog01 : public QDialog
{
    Q_OBJECT

public:
    explicit Dialog01(QWidget *parent = 0);
    ~Dialog01();

public slots:
    void recvText(QString text);

private:
    Ui::Dialog01 *ui;
};

#endif // DIALOG01_H

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dialog01.cpp

#include "ui_dialog01.h"
 
#include "dialog01.h"
 
Dialog01::Dialog01(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Dialog01)
{
    ui->setupUi(this);
}
 
Dialog01::~Dialog01()
{
    delete ui;
}
 
void Dialog01::recvText(QString text)
{
    ui->lineEdit->setText(text);
}

#include "ui_dialog01.h"

#include "dialog01.h"

Dialog01::Dialog01(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Dialog01)
{
    ui->setupUi(this);
}

Dialog01::~Dialog01()
{
    delete ui;
}

void Dialog01::recvText(QString text)
{
    ui->lineEdit->setText(text);
}

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main.cpp

#include <QApplication>
 
#include "maindialog.h"
 
#include "dialog.h"
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    //MainDialog w;
    //w.show();
 
    Dialog d;
    d.show();
 
    return a.exec();
}

#include <QApplication>

#include "maindialog.h"

#include "dialog.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    //MainDialog w;
    //w.show();

    Dialog d;
    d.show();

    return a.exec();
}

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