QListWidget交换位置

#include <QtGui> #include <QtWidgets> #include "projectlistwidget.h" ProjectListWidget::ProjectListWidget(QWidget *parent) : QListWidget(parent) { setAcceptDrops(true); } void ProjectListWidget::mousePressEvent(QMouseEvent *event) { if (event->button() == Qt::LeftButton) startPos = event->pos(); QListWidget::mousePressEvent(event); } void ProjectListWidget::mouseMoveEvent(QMouseEvent *event) { if (event->buttons() & Qt::LeftButton) { int distance = (event->pos() - startPos).manhattanLength(); if (distance >= QApplication::startDragDistance()) performDrag(); } QListWidget::mouseMoveEvent(event); } void ProjectListWidget::dragEnterEvent(QDragEnterEvent *event) { ProjectListWidget *source = qobject_cast<ProjectListWidget *>(event->source()); if (source && source != this) { event->setDropAction(Qt::MoveAction); event->accept(); } } void ProjectListWidget::dragMoveEvent(QDragMoveEvent *event) { ProjectListWidget *source = qobject_cast<ProjectListWidget *>(event->source()); if (source && source != this) { event->setDropAction(Qt::MoveAction); event->accept(); } } void ProjectListWidget::dropEvent(QDropEvent *event) { ProjectListWidget *source = qobject_cast<ProjectListWidget *>(event->source()); if (source && source != this) { addItem(event->mimeData()->text()); event->setDropAction(Qt::MoveAction); event->accept(); } } void ProjectListWidget::performDrag() { QListWidgetItem *item = currentItem(); if (item) { QMimeData *mimeData = new QMimeData; mimeData->setText(item->text()); QDrag *drag = new QDrag(this); drag->setMimeData(mimeData); drag->setPixmap(QPixmap(":/images/person.png")); if (drag->exec(Qt::MoveAction) == Qt::MoveAction) delete item; } }