How to connect mainwindow and dialog using signal,slot

[harvey_slash]

my connect is in the mainwindow constructor.

I put connect here now

dialog =new Dialog();
     connect(ui->lineEdit, SIGNAL(textEdited(QString)), dialog, SLOT(seText(QString)));
    dialog->show();

dialog =new Dialog();
     connect(ui->lineEdit, SIGNAL(textEdited(QString)), dialog, SLOT(seText(QString)));
    dialog->show();

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its not showing any error, but the text is not getting displayed
(I tried textChanged and textEdited ,both)