Qt官方示例可拖拽本文

可对文本进行拖动到指定位置。

部分主要代码

• 当被鼠标拖动的对象进入其容器范围内时触发此事件

void DragWidget::dragEnterEvent(QDragEnterEvent *event){    if (event->mimeData()->hasText()) {        if (event->source() == this) {            event->setDropAction(Qt::MoveAction);            event->accept(); /* 接受拖拽事件 */        } else {            event->acceptProposedAction();        }    } else {        event->ignore();    }}

在一个拖动过程中，释放鼠标键时触发此事件

void DragWidget::dropEvent(QDropEvent *event){    if (event->mimeData()->hasText()) {        const QMimeData *mime = event->mimeData();        QStringList pieces = mime->text().split(QRegularExpression(QStringLiteral("\\s+")),                             QString::SkipEmptyParts);        QPoint position = event->pos();        QPoint hotSpot;        QByteArrayList hotSpotPos = mime->data(hotSpotMimeDataKey()).split(' ');        if (hotSpotPos.size() == 2) {            /* 松开拖拽设置为当前位置 */            hotSpot.setX(hotSpotPos.first().toInt());             hotSpot.setY(hotSpotPos.last().toInt());        }        for (const QString &piece : pieces) {            QLabel *newLabel = createDragLabel(piece, this);            newLabel->move(position - hotSpot);            newLabel->show();            newLabel->setAttribute(Qt::WA_DeleteOnClose);            position += QPoint(newLabel->width(), 0);        }        if (event->source() == this) {            event->setDropAction(Qt::MoveAction);            event->accept(); /* 接受拖拽事件 */        } else {            event->acceptProposedAction();        }    } else {        event->ignore();    }    for (QWidget *widget : findChildren<QWidget *>()) {        if (!widget->isVisible())            widget->deleteLater();    }}

• 捕获鼠标按下事件

void DragWidget::mousePressEvent(QMouseEvent *event){    QLabel *child = qobject_cast<QLabel*>(childAt(event->pos()));    if (!child)        return;    QPoint hotSpot = event->pos() - child->pos();    QMimeData *mimeData = new QMimeData;    mimeData->setText(child->text());    mimeData->setData(hotSpotMimeDataKey(),                      QByteArray::number(hotSpot.x()) + ' ' + QByteArray::number(hotSpot.y()));    qreal dpr = window()->windowHandle()->devicePixelRatio();    QPixmap pixmap(child->size() * dpr);    pixmap.setDevicePixelRatio(dpr);    child->render(&pixmap);    QDrag *drag = new QDrag(this);    drag->setMimeData(mimeData);    drag->setPixmap(pixmap);    drag->setHotSpot(hotSpot);    Qt::DropAction dropAction = drag->exec(Qt::CopyAction | Qt::MoveAction, Qt::CopyAction);    if (dropAction == Qt::MoveAction)        child->close();}

关于更多

• 在QtCreator软件可以找到：

• 或在以下Qt安装目录找到

C:\Qt\{你的Qt版本}\Examples\{你的Qt版本}\widgets\draganddrop\draggabletext

• 相关链接

https://doc.qt.io/qt-5/qtwidgets-draganddrop-draggabletext-example.html

• Qt君公众号后台回复『Qt示例』获取更多内容。