access on main window from anothe window (e.g Dialog)

[Malek]

Zlatomir .Sorry for the delay.

Thank you for your replay.
I think that your suggestion is more professional ,but I have found another simple solution by make function in class dialog.This functoin have to return the content of lineEdit.
e.g

QString dialog::getLineEditText() const
{
    return ui->lineEdit->text();
}

QString dialog::getLineEditText() const
{
    return ui->lineEdit->text();
}

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Then call it like after execute the dialog

if (x.exec() == QDialog::Accepted)
        ui->lineEdit->setText(x.getLineEditText());

if (x.exec() == QDialog::Accepted)
        ui->lineEdit->setText(x.getLineEditText());

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THANK YOU FOR YOUR INTEREST.