QComboBox *combo = new QComboBox(this); combo->addItem("Option 1"); combo->addItem("Option 2"); combo->addItem("Option 3"); combo->setItemData(0, 100, Qt::UserRole); combo->setItemData(1, 200, Qt::UserRole); combo->setItemData(2, 300, Qt::UserRole);
struct CustomData { int value1; QString value2; }; QComboBox *combo = new QComboBox(this); combo->addItem("Option 1"); combo->addItem("Option 2"); combo->addItem("Option 3"); CustomData data1 = { 100, "Data for option 1" }; CustomData data2 = { 200, "Data for option 2" }; CustomData data3 = { 300, "Data for option 3" }; combo->setItemData(0, QVariant::fromValue(data1), Qt::UserRole); combo->setItemData(1, QVariant::fromValue(data2), Qt::UserRole); combo->setItemData(2, QVariant::fromValue(data3), Qt::UserRole);In this example, we create a custom data structure to store multiple values. We then create a QComboBox and add three items. We use setItemData to assign instances of our custom data structure to each item. These examples use the Qt library's QComboBox class.