Show a context menu when the a column in a QTableView is selected

RDiGuida

Hello, as the title says I am trying to implement a context menu that appears on left click if a whole column is selected in a TableView.

In my MainWindow I have these attributes

private:
    QString mFilePath;
    DatasetModel model;
    myTabView* view;
    DataFrame data;
    TabSelModel* selModel;

where myTabView is just a reimplemented QTableView. I installed an event filter in the constructor of the MainWindow like this view->installEventFilter(this); and I implemented di eventfilter in the Main Window like this

bool MainWindow::eventFilter(QObject *watched, QEvent *e)
{
    if(watched==view && e->type()==QEvent::MouseButtonPress)
    {
        QModelIndexList idxl = view->selectedIndexes();
        QMouseEvent *mou = static_cast<QMouseEvent*>(e);
        if(mou->button()==Qt::RightButton && selModel->ColSelected.first)
        {
            ShowContextMenu(mou->pos());
            return true;
        }
    }
    return QWidget::eventFilter(watched,e);
}

Where ColSelected is a QPair implemented in a slot of my TabSelModel (a reimplemented QItemSelectionModel). The slot looks like this

void TabSelModel::CheckSelection(const QModelIndex& mod,)
{
    qDebug() << "Inside mod.column=" << mod.column();

    if(isColumnSelected(mod.column(),mod))                 //never evaluates to true
        ColSelected = qMakePair(true,mod);
    else
        ColSelected.first = false;
}

which is connected to a simple SIGNAL(currentChanged()) from the selection model. I manage to get into the slot (the qDebug outputs the correct column) but the first condition never evaluates to true. How is that possible?

Chris Kawa

isColumnSelected checks for selection in the parent given in second param, so this should rather be
if(isColumnSelected(mod.column(),mod->parent())).

RDiGuida

I changed the code but still I never reach ColSelected = qMakePair(true,mod);.

Chris Kawa

Maybe a silly question, but is the whole column actually selected ? If you get selected items in that slot does that contain all indices in the column?

RDiGuida

Actually I get all the rows but I get the previously selected column. The code is

void TabSelModel::CheckSelection(const QModelIndex& mod)
{
    qDebug() << "Inside mod.column=" << mod.column();
    QModelIndexList ls = selectedIndexes();

    foreach(QModelIndex i, ls)
        qDebug() << i.column() << "," << i.row();

And the first time I select the first column of the table the output is just

Inside mod.column= 0

When I select the next column I get

Inside mod.column= 1
0 , 0
0 , 1
0 , 2
0 , 3
...
0, 66

How is that possible?

Chris Kawa

Most things in c++ are indexed from 0, so first column has index 0, second 1 and so on.

RDiGuida

I know, what is strange is that mod.column() evaluates to 1 and selectedIndexes()[0].column() evaluates to 0 while they should be the same.

RDiGuida

May it be related to some sort of dragging of the previous selection?