QTreeView如何禁用拖动指示器

Question

如何禁用 QTreeView 中的拖动指示器？ QTreeView 创建：

m_treeViewUnit = new QTreeView(dock);
m_treeViewUnit->setFrameStyle(QFrame::NoFrame);
m_treeViewUnit->setHeaderHidden(true);
m_treeViewUnit->setEditTriggers(QAbstractItemView::NoEditTriggers);
m_treeViewUnit->setExpandsOnDoubleClick(false);
m_treeViewUnit->setContextMenuPolicy(Qt::CustomContextMenu);
m_treeViewUnit->setDragEnabled(true);
m_treeViewUnit->setDefaultDropAction(Qt::IgnoreAction);

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