Can a top level item have a checkbox?

SRaD

I'm trying to create a TreeView that looks like this where there is a checkbox in the top level items.

[] Item1
    ItemA
    ItemB
[] Item2 
    ItemA
    ItemB
[] Item3
    ItemA
    ItemB

Yet, I'm not seeing what I expect. Checkboxes appear for ItemA and itemB of Item1 only. When I dynamically create my tree, here is how I add items to the tree ...

The TreeModel is initialized as:

QVector<QVariant> rootData;
rootData << "Col1" << "Col2";

parentItem = new MyTreeItem(rootData);

model = new MyTreeModel(parentItem);

And items are add by user like:

// ...
QCheckBox *cb = new QCheckBox;
cb->setCheckState(Qt::Checked);

QVector<QVariant> data;
QVector<QVariant> data1;
QVector<QVariant> data2;

data << name << QVariant::fromValue(cb);
data1 << a1_name; // <-- just qstring names
data2 << a2_name;
                                                                           
MyTreeItem *item = new MyTreeItem(data, parentItem);
item->setLabel(itemName);

parentItem->appendChild(item);

MyTreeItem *item1 = new MyTreeItem(data1, item);
item1->setLabel(itemName1);

item->appendChild(item1);

MyTreeItem *item2 = new MyTreeItem(data2, item);
item2->setLabel(itemName2);

item->appendChild(item2);

And here's the flags() of the TreeModel.

Qt::ItemFlags MyTreeModel::flags(const QModelIndex &index) const
{   
    if (!index.isValid())
        return 0;

    Qt::ItemFlags flags;

    if (index.column() <= 1) {
        
        flags = Qt::ItemIsEnabled | Qt::ItemIsUserCheckable;
    }

     return flags;
 }

Any thoughts as to why this isn't drawing the tree I'm looking for?

CKurdu

Hi SRad,
I am not sure that can solve your problem but I think flags method should be like that.

Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return 0;

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

    return  QAbstractItemModel::flags(index);;
}

And also you should imlement data and setData mehtods like below

QVariant TreeModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();

   TreeItem *item = static_cast<TreeItem*>(index.internalPointer());
   if ( role == Qt::CheckStateRole && index.column() == 0 && !index.parent().isValid() )
        return static_cast< int >( item->isChecked() ? Qt::Checked : Qt::Unchecked );

    if (role != Qt::DisplayRole)
        return QVariant();


    return item->data(index.column());
}
//! [3]
bool TreeModel::setData(const QModelIndex &index, const QVariant &value, int role)
{

    TreeItem *item = static_cast<TreeItem*>(index.internalPointer());
    if(role == Qt::CheckStateRole)
    {

                if(item->isChecked())
                    item->setChecked(false);
                else
                    item->setChecked(true);
                emit dataChanged(index, index);
                return true;
    }

    if (role != Qt::EditRole)
        return false;


    return QAbstractItemModel::setData(index,value,role);
}

Result

If you can show your MyTreeItem content, I can help much.

SRaD

@CKurdu - Thanks for the help, this worked out great.

CKurdu

@SRaD
You are welcome. Good luck.