Changing the value of a dial slide with an input in QT? - c++

Question

Well, I am kind of stuck on this issue - I am trying to change the value of a dial slider and I want to change it using an input with QLineEdit input field and so far I couldn't find anything that could have helped me on the internet.
Code snip
void MainWindow::on_lineEditGain_textChanged(const QString &arg1)
{
QString getVal=ui->lineEditGain->text();
// qint16 intVal = getVal.split(" ")[0].toInt();
connect(getVal, SIGNAL(textChanged(QString)), this, SLOT(setValue(QString)));
}

Answer 1

Create slots:
private slots:
void MySlot(QString text);
In the constructor connect textChanged() with MySlot():
connect(lineedit, &QLineEdit::textChanged, this, &YourWidget::MySlot);
and then
void YourWidget::MySlot(QString text)
{
QRegExp re("\\d*"); // a digit (\d), zero or more times (*)
if (re.exactMatch(text)){
int value = text.toInt();
if(value >= -127 && value<=127)
slider->setValue(value);
}
}
You could also place a QValidator
lineedit->setValidator( new QIntValidator(-127, 127, this) );
In your case:
void MainWindow::on_lineEditGain_textChanged(const QString &arg1)
{
QRegExp re("\\d*"); // a digit (\d), zero or more times (*)
if (re.exactMatch(arg1)){
int value = arg1.toInt();
if(value >= -127 && value<=127)
ui->slider->setValue(value);
}
}