QLineEdit change text weight on activation - c++

Question

I want to make QLineEdit looks like QLabel with bold text if it's inactive and like QLineEdit with normal weight if active. In my understanding "active" = when text cursor shown and user can enter a text.
I tried to apply this css:
QLineEdit {
font-weight: normal;
border: 1px solid black;
}
QLineEdit:!focus {
font-weight: bold;
border: none;
}
Border works as expected, but font-weight is always bold.
I was thinking of creating my class to handle activation event, but can't found anything related with it.
I will be very thankful if somebody can help me.

Answer 1

You need to get your custom slot for the focusChanged event. There you can change the font like this:
QFont font = ui->lineEdit_search->font();
font.setWeight(QFont::Bold); // or
font.setWeight(QFont::Normal);
ui->lineEdit_search->setFont(font);
An example where I handled a LineEdit search box is here, but you have to customize it with the bold text.
void MainWindow::focusChanged(QWidget* old, QWidget* now)
{
if(now != NULL &&
now->objectName() == "lineEdit_search")
{
if(ui->lineEdit_search->text() == tr("Search..."))
{
ui->lineEdit_search->clear();
QPalette *palette = new QPalette();
palette->setColor(QPalette::Text,Qt::black);
ui->lineEdit_search->setPalette(*palette);
delete palette;
}
}
else if(old != NULL &&
old->objectName() == "lineEdit_search")
{
if(ui->lineEdit_search->text().isEmpty())
{
ui->lineEdit_search->setText(tr("Search..."));
QPalette *palette = new QPalette();
palette->setColor(QPalette::Text,Qt::gray);
ui->lineEdit_search->setPalette(*palette);
delete palette;
}
}
}

Answer 2

When you turn your line edit to inactive,
//Set your line edit to read only
yourLineEdit->setReadOnly(true);
//Get your widget background color
const QColor clr = this->palette().color(QWidget::backgroundRole());
//Set the widget background color to both the line edit background and its border
QString backGroundstyle = "background-color: rgb(%1, %2, %3);";
QString borderStyle = "border: 1px solid rgb(%1, %2, %3);";
yourLineEdit->setStyleSheet(backGroundstyle.arg(clr.red()).arg(clr.green()).arg(clr.blue()) + borderStyle.arg(clr.red()).arg(clr.green()).arg(clr.blue()));
When you turn line edit to active
//Make your line edit read-write
yourLineEdit->setReadOnly(false);
//Bring back your styles.
QString backGroundstyle_active = "background-color: white;";
QString borderStyle_active = "border: 1px solid black;";
yourLineEdit->setStyleSheet(backGroundstyle_active + borderStyle_active);