How to make a countdown was displayed in the label,that's what I did but I have displays the current time
QTextStream in(&file);
QTime start = QTime::currentTime();
while (!in.atEnd())
{
QString line = in.readLine();
if (line.contains(v) || line.contains(s) || line.contains(k) || line.contains(m) || line.contains(q) || line.contains(r))
ui.textEdit->append(line);
ui.lineEdit_6->setText(QString().number(ui.textEdit->document()->lineCount()));
}
Finish QTime = QTime::currentTime();
QString time;
ui.label->setText((finish.toString("")));
}