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c++qtlistviewsignals

QListView selectionModel not sending selectionChanged signal

I have an interface with two QListViews, where the left determines what is displayed in the right: layout

To update the list on the right, I have the following function:

void CodePlug::handleSelectionChanged()
{
    QModelIndex portIndex = ui->listPorts->currentIndex();
    QString portItemText = portIndex.data(Qt::DisplayRole).toString();
    ui->listPlugs->setModel(ListModelFromMap(plugs[portItemText]));
    currentPort = portItemText;
    qDebug(currentPort.toStdString().data());
}

and it's connected to the selectionChanged signal here:

CodePlug::CodePlug(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::CodePlug)
{
    ui->setupUi(this);
    ui->listPorts->setModel(ListModelFromMap(ports));
    QModelIndex portIndex = ui->listPlugs->currentIndex();
    QString portItemText = portIndex.data(Qt::DisplayRole).toString();
    ui->listPlugs->setModel(ListModelFromMap(plugs[portItemText]));

    connect(ui->listPorts->selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)), this, SLOT(handleSelectionChanged()));
}

However, changing the selected item by either the keyboard or the mouse never triggers handleSelectionChanged(). It doesn't generate any errors, it just doesn't do anything. Could anybody give me an idea why?

Solution

  • I figured it out, and it was silly.

    When a new item was added to the list, I was calling setModel() on listPorts, which of course broke the connection. I suspect there is a better way to handle the change, so I'll try and fix that but for now, I'm reconnecting every time the model is changed.