QT connect Signal from QDialog with Main Window
<p>I'm probably missing something so basic, that I'll be ashamed once you point it out to me, but right now I've been working on this matter for nearly 3 days, so I think it might be time to get some help.</p>

<p>I have a QWizardProject on qt5 and for one of these pages I want a QPushButton, that launches a new Dialog, where I have a QCheckbox (among others). Signals from the QCheckbox should change the QLineEdit on the QWizardPage.
Sounds simple enough, I just can't get it to work - at all. I've tried out so many different versions of that (most of them failed building). The most recent version just does nothing. Thanks for any help in advance!</p>

<p>main.h</p>

<pre><code>#ifndef main_H
#define main_H

#include &lt;QWizard&gt;
#include &lt;QtWidgets&gt;

class QCheckBox;
class QLabel;
class QLineEdit;
class QRadioButton;

class OMVGguiWizard : public QWizard
{
    Q_OBJECT

public:
    enum { Page_Main1, Page_Main2, Page_Main3};

    OMVGguiWizard(QWidget *parent = 0);
};

class Page_Main3 : public QWizardPage
{
    Q_OBJECT;

public:
    Mainpage_3(QWidget *parent = 0);

private slots:
    void btnOptionsbuttonsClicked(QString mode);
private:
    QPushButton *OptionsButton;
    QLineEdit *receiver;
};

class FindDialog : public QDialog
{
     Q_OBJECT

public:
     FindDialog(QWidget *parent = 0);

private:
     QCheckBox *checkbox;
     QGridLayout *mainLayout;
};

#endif
</code></pre>

<p>main.cpp</p>

<pre><code>Page_Main3::Page_Main3(QWidget *parent)
    : QWizardPage(parent)
{
    // ...

    DensifyOptionsButton = new QPushButton(tr("Densify Settings"));
    receiver = new QLineEdit(tr("empty"));

    connect(OptionsButton, &amp;QPushButton::clicked, [this]() { btnOptionsbuttonsClicked("field1"); });

    // ...
}

void Page_Main3::btnOptionsbuttonsClicked(QString mode)
{
     FindDialog *dialog = new FindDialog;
     dialog-&gt;show();
}

void Page_Main3::checkboxClicked()
{
receiver-&gt;setText("test");
}

FindDialog::FindDialog(QWidget *parent)
      : QDialog(parent)
{
     checkbox = new QCheckBox(tr("Advanced Options"));
     mainLayout = new QGridLayout;
     mainLayout-&gt;addWidget(checkbox);
     setLayout(mainLayout);
     connect(checkbox, SIGNAL(clicked()), this, SLOT(Page_Main3::checkboxClicked() ) );
}
</code></pre>