Qt QComboBox with different background color for each item?

Question

Greetings all,

Is there a way to set a different background color for each item in a QComboBox ?

Thank in advance

Answer 1

I guess the only way to do it would be to write your own model, inheriting QAbstractListModel, reimplementing rowCount()and data() where you can set the background color for each item (using the BackgroundRole role).

Then, use QComboBox::setModel() to make the QComboBox display it.

Here is a simple example, where I created my own list model, inheriting QAbstractListModel :

class ItemList : public QAbstractListModel
{
   Q_OBJECT
public:
   ItemList(QObject *parent = 0) : QAbstractListModel(parent) {}

   int rowCount(const QModelIndex &parent = QModelIndex()) const { return 5; }
   QVariant data(const QModelIndex &index, int role) const {
      if (!index.isValid())
          return QVariant();

      if (role == Qt::BackgroundRole)
         return QColor(QColor::colorNames().at(index.row()));

      if (role == Qt::DisplayRole)
          return QString("Item %1").arg(index.row() + 1);
      else
          return QVariant();
   }
};

It is now easy to use this model with the combo box :

comboBox->setModel(new ItemList);