connect(m_tree,itemChanged(QTreeWidgetItem*,int),this,SLOT(saveModify(QTreeWidgetItem*,int));

QTreeWidgetItem *item=new QTreeWidgetItem(m_tree);
item->setText(0,"hello");
item->setFlags(item->flags()|Qt::ItemIsEditable); // 设置可编辑属性

// 添加子节点
void TreeEdit::addNode()
{
    QTreeWidgetItem *curItem=m_tree->currentItem();
    QTreeWidgetItem *newItem=new QTreeWidgetItem(curItem);

    // 添加子节点
    curItem->addChild(newItem);

    // 使用QTextEdit的信号
    QLineEdit *lineEdit=new QLineEdit(this);
    connect(lineEdit,SIGNAL(editingFinished()),this,SLOT(finishEdit()));

    // 设置widget
    m_tree->setItemWidget(newItem,0,lineEdit);
    m_tree->expandItem(curItem);

    // 选中项
    m_tree->setCurrentItem(newItem);

    // 设置默认值
    lineEdit->setText("default");
    lineEdit->setSelection(0,7);
}

// 编辑完成后对应的槽函数
void TreeEdit::finishEdit()
{
    // 编辑完成后,移除widget,还原树
    QTreeWidgetItem *curItem=m_tree->currentItem();
    QLineEdit *edit=qobject_cast<QLineEdit*>(m_tree->itemWidget(curItem,0));
    if(!edit)
        return;

    QString text=edit->text();

    // 移除widget
    m_tree->removeItemWidget(curItem,0);

    // 还原值
    curItem->setText(0,text);
}