add checkbox to qtreewidgetitem

Question

i want to add a check box to my qtreewigetitem, i tried this code to setflag, then i add item is selectable for sake of maybe this will solve my problem but nothing happened, would you please help me how can i add check box to my item? thank you in advance

m_eventList->addTopLevelItem(new QTreeWidgetItem);
       QTreeWidgetItem *item = m_eventList->topLevelItem(m_eventList->topLevelItemCount()-1)

    item->setFlags(item->flags() | Qt::ItemIsUserCheckable |Qt::ItemIsSelectable);

Answer 1

The ItemIsUserCheckable flag is already set by default in QTreeWidgetItem, so that's not the issue.

All you need is to do

item->setCheckState(Qt::Unchecked);

and you should see a checkbox.

Answer 2

Try to reorganize your code:

QTreeWidgetItem* item = new QTreeWidgetItem();
item->setFlags(item->flags() | Qt::ItemIsUserCheckable | Qt::ItemIsSelectable);
item->setCheckState(Qt::Checked);
m_eventList->addTopLevelItem(item);

Another method would be to write your own model and overwrite the flags() method. In this method, you return

Qt::ItemFlags flags = Qt::ItemIsEnabled | Qt::ItemIsSelectable;
if (index.column() == 0)
{
    flags |= Qt::ItemIsUserCheckable;
}
return flags;

Answer 3

Qt::ItemIsUserCheckable and Qt::ItemIsSelectable are default setting for QTreeWidget.

item->setCheckState(column, Qt::Unchecked) is Okay.

https://doc.qt.io/qt-5/qtreewidgetitem.html#flags