的Qt：重新排序的ListView項目使用拖放

Question

我已經實現了拖動下面的方法和下降

void mousePressEvent(QMouseEvent *event); 
void dragEnterEvent(QDragEnterEvent *event); 
void dragMoveEvent(QDragMoveEvent *event); 
void dropEvent(QDropEvent *event); 
void startDrag(Qt::DropActions supportedActions); 

我有而QListView並使用setIndexWidget（），以顯示在每個modelindex自定義窗口小部件。我試圖安排使用拖放在列表視圖中的項目，但是在ListView的項目不妥善安排，我寫了下面的代碼： -

MyListView::MyListView(QWidget *parent) : 
    QListView(parent) 
{ 
    setSelectionMode(QAbstractItemView::SingleSelection); 
    setDragEnabled(true); 
    setAcceptDrops(true); 
    setDragDropMode(QAbstractItemView::InternalMove); 
    setDefaultDropAction(Qt::MoveAction); 
    setDropIndicatorShown(true); 
    setDragDropOverwriteMode(true); 
    setMovement(QListView::Snap); 
    setFlow(QListView::TopToBottom); 
// setStyleSheet("QListView::item {" 
//     "height: 50px;" 
//     "border: 1px solid black;}"); 
} 

void MyListView::setModel(QAbstractItemModel *model) 
{ 
    QListView::setModel(model); 

    for (int i=0; i<model->rowCount(); i++) 
    { 
     QModelIndex index = model->index(i,0); 
     ListWidgetItem *widget = new ListWidgetItem; 
     widget->setIndex(i);; 
     setIndexWidget(index,widget); 
    } 
} 

void MyListView::mousePressEvent(QMouseEvent *event) 
{ 
    QModelIndex i = indexAt(event->pos()); 
    if (event->button() == Qt::LeftButton) 
    { 
     ListWidgetItem *item = dynamic_cast<ListWidgetItem *>(childAt(event->pos())); 

     if (!item) 
      return; 

     y = event->pos().y()-item->pos().y(); 

     QModelIndex indx = indexAt(event->pos()); 
     currentPixmap = QPixmap::grabWidget(item); 
     dragPoint = event->pos(); 
     if (event->pos().x() < 25 && indx.row() >= 0) 
      startDrag(Qt::MoveAction); 
    } 
} 

void MyListView::dragEnterEvent(QDragEnterEvent *event) 
{ 
    if (event->mimeData()->hasFormat("application/x-QListView-DragAndDrop")) 
    { 
     event->accept(); 
    } 
    else 
     event->ignore(); 
} 

void MyListView::dragMoveEvent(QDragMoveEvent *event) 
{ 
    ListWidgetItem *item = dynamic_cast<ListWidgetItem *>(childAt(event->pos())); 
    if(!item) 
     return; 

    itemList.append(item); 

    foreach (ListWidgetItem *widget,itemList) 
    { 
     if (widget == item) 
      widget->setStyleSheet("#ListWidget { border-top: 2px solid red; }"); 
     else 
      widget->setStyleSheet("#ListWidget { border-top: 0px solid black; }"); 
    } 
    if (event->mimeData()->hasFormat("application/x-QListView-DragAndDrop")) 
    { 
     event->setDropAction(Qt::MoveAction); 
     event->accept(); 
    } else 
     event->ignore(); 
} 

void MyListView::dropEvent(QDropEvent *event) 
{ 
    if (event->mimeData()->hasFormat("application/x-QListView-DragAndDrop")) { 
     QByteArray itemData = event->mimeData()->data("application/x-QListView-DragAndDrop"); 
     QDataStream dataStream(&itemData,QIODevice::ReadOnly); 

     QPoint itemPoint; 
     dataStream >> itemPoint; 

     ListWidgetItem *item = dynamic_cast<ListWidgetItem *> (childAt(itemPoint)); 
     if(!item) 
      return; 

     QModelIndex index = indexAt(event->pos()); 
     int row = index.row(); 
     model()->insertRows(row,1); 

     QModelIndex idx =model()->index(row,0); 
     setIndexWidget(idx,item); 

     if (event->source() == this) { 
      event->setDropAction(Qt::MoveAction); 
      foreach (ListWidgetItem *widget,itemList) 
      { 
       widget->setStyleSheet("#ListWidget { border-top: 0px solid black; }"); 
      } 
      itemList.clear(); 
//   model()->removeRow(n+1); 

      event->accept(); 
     } 
    } else{ 
     event->ignore(); 
    } 
} 

void MyListView::startDrag(Qt::DropActions supportedActions) 
{ 
    QByteArray itemData; 
    QDataStream dataStream(&itemData, QIODevice::WriteOnly); 

    ListWidgetItem *item = dynamic_cast<ListWidgetItem *>(childAt(dragPoint)); 

    dataStream << dragPoint; 

    QMimeData *mimeData = new QMimeData; 
    mimeData->setData("application/x-QListView-DragAndDrop", itemData); 

    drag = new QDrag(this); 
    drag->setMimeData(mimeData); 
    drag->setHotSpot(mapToParent(QPoint(item->x(),y))); 
    drag->setPixmap(currentPixmap); 

    QModelIndex indx = indexAt(dragPoint); 
    if (drag->exec(Qt::MoveAction | Qt::CopyAction) == Qt::MoveAction) 
    { 
     model()->removeRow(indx.row()); 
    } 

} 

我已經搜查，但沒得到任何妥善的解決辦法。 謝謝

Answer 1

你看過QAbstractItemView的DragDropMode嗎？ http://qt-project.org/doc/qt-4.8/qabstractitemview.html#dragDropMode-prop

聽起來好像這個ius你試圖實現什麼。