I guess no one knows about it. I've been asking the same question for 2 days, and no one answers.

I find a toDoList project about drag&drop. And I wonder Can I get the item that dragging or dropped. I'm reading the documentation for 2 days. I implement the methods.

protected:
    void dragEnterEvent( QDragEnterEvent *anEvent ) override;
    void dragMoveEvent( QDragMoveEvent *anEvent ) override;
    void dragLeaveEvent( QDragLeaveEvent *anEvent ) override;
    void dropEvent( QDropEvent *anEvent ) override;

There are 2 listviews and toolbar. I add add and remove to the toolbar.
I can drag or drop but, I can't get text of the the items dragging. This is the main code. And I really wonder, we override the methods right. But we do not connect the methods to something. How does the method works ?

todolist::todolist(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::todolist)
{
    QWidget* pWidget = new QWidget(this);
        pWidget->setStyleSheet("background-color: #ECF0F1");
        setCentralWidget(pWidget);

        QVBoxLayout* pMainLayout = new QVBoxLayout();
        pWidget->setLayout(pMainLayout);

        QLabel* pwTitle = new QLabel("To Do List", this);
        pMainLayout->addWidget(pwTitle);
        pwTitle->setAlignment(Qt::AlignCenter);
        pwTitle->setStyleSheet("font-size: 30pt; margin: 10%;");

        QHBoxLayout* pHLayoutLabels = new QHBoxLayout();
        pMainLayout->addLayout(pHLayoutLabels);

        QLabel* plblPending = new QLabel("Pending", this);
        plblPending->setStyleSheet("font-size: 15pt;");
        pHLayoutLabels->addWidget(plblPending);

        QLabel* plblCompleted = new QLabel("Completed", this);
        plblCompleted->setStyleSheet("font-size: 15pt;");
        pHLayoutLabels->addWidget(plblCompleted);

        QHBoxLayout* pHLayout = new QHBoxLayout();
        pMainLayout->addLayout(pHLayout);

        m_pwPending = new QListView(this);
        m_pwPending->setDragEnabled(true);
        m_pwPending->setAcceptDrops(true);
        m_pwPending->setDropIndicatorShown(true);
        m_pwPending->setDefaultDropAction(Qt::MoveAction);
        pHLayout->addWidget(m_pwPending);

        m_pwCompleted = new QListView(this);
        m_pwCompleted->setDragEnabled(true);
        m_pwCompleted->setAcceptDrops(true);
        m_pwCompleted->setDropIndicatorShown(true);
        m_pwCompleted->setDefaultDropAction(Qt::MoveAction);
        pHLayout->addWidget(m_pwCompleted);

        m_pwPending->setModel(new QStringListModel());
        m_pwCompleted->setModel(new QStringListModel());

        m_pwPending->setStyleSheet
        ("QListView { font-size: 20pt; font-weight: bold; }"
         "QListView::item { background-color: #E74C3C; padding: 10%;"
         "border: 1px solid #C0392B; }"
         "QListView::item::hover { background-color: #C0392B }");

        m_pwCompleted->setStyleSheet
        ("QListView { font-size: 20pt; font-weight: bold; }"
         "QListView::item { background-color: #2ECC71; padding: 10%;"
         "border: 1px solid #27AE60; }"
         "QListView::item::hover { background-color: #27AE60 }");


        QToolBar* pToolBar = new QToolBar(this);
        addToolBar(pToolBar);

        m_pActAdd = new QAction(this);
            m_pActAdd->setIcon(QIcon(":/resources/add.png"));
            connect(m_pActAdd, &QAction::triggered, this, &todolist::onAdd);

            m_pActRemove = new QAction(this);
            m_pActRemove->setIcon(QIcon(":/resources/remove.png"));
            connect(m_pActRemove, &QAction::triggered, this, &todolist::onRemove);

        pToolBar->addAction(m_pActAdd);
        pToolBar->addAction(m_pActRemove);

        setAcceptDrops(true);
}

void todolist::onAdd()
{
    m_pwPending->model()->insertRow(m_pwPending->model()->rowCount());
    QModelIndex oIndex = m_pwPending->model()->index(
    m_pwPending->model()->rowCount() - 1, 0);

    m_pwPending->edit(oIndex);

}

void todolist::onRemove()
{
    QModelIndex oIndex = m_pwPending->currentIndex();
    m_pwPending->model()->removeRow(oIndex.row());
}
void todolist::dropEvent(QDropEvent* event) {
    const QMimeData* mimeData = event->mimeData();
    QString temp;
    if(mimeData->hasText()) {
        temp = mimeData->text();
    }

    QMessageBox::information(this,"x",temp);
}

void todolist::dragEnterEvent(QDragEnterEvent *anEvent)
{
    anEvent->setAccepted(true);
}

void todolist::dragMoveEvent(QDragMoveEvent *anEvent)
{

}

void todolist::dragLeaveEvent(QDragLeaveEvent *anEvent)
{

}
todolist::~todolist()
{
    delete ui;
}

CodePudding user response：

I used the recommended site

Notes:

• There is no custom list view necessary. &emdash; The QListView can be used but Drag as well as Drop have to be configured. Thereby, a QListView can be configured for drag and drop in contrast to my sample code.
• Contrary to what I recommended in comments, there is admittedly no need to override dragEnterEvent() (or company). These events are already overridden in QListView and consult the corresponding model for drag & drop support.
• There is even no custom string list model necessary. After configuration of list views for drag & drop, it started to work with QStringListModel as well. I derived QStringListModel to demonstrate how to customize drag & drop.
• The overridden functions mimeData(), canDropMimeData(), and dropMimeData() are not necessary as well. Drag & drop will work even without them. (I tested this before I added them.) I don't know what MIME data is used to communicate the dragged contents. As drag site and drop site are the same widget class in my sample, it's not surprising that the dragged data can be dropped (however it's stored internally).