只能记忆展开状态，滚动状态没支持，因为这个树控件 ，可能不使用了 ，半成品

#ifndef QTREEVIEWNOKBD_H

#define QTREEVIEWNOKBD_H

#include "Header.h"

typedef struct _NodeP

{

    int nRowNo;

    std::vector<_NodeP> arChildren;

}NodeExpand;

class QTreeViewNoKbd : public QTreeView

{

public:

    QTreeViewNoKbd();

    void keyPressEvent(QKeyEvent *event);

    void startRemeberNode();

    void startExpandNode();

private:

    void recursiveRememberNodeState(NodeExpand& ne, QModelIndex root);

    void recursiveExpandNode(NodeExpand& ne, QModelIndex root);

    NodeExpand m_nodeExpand;

};

#endif // QTREEVIEWNOKBD_H

#include "TreeViewNoKbd.h"


QTreeViewNoKbd::QTreeViewNoKbd()
{
    setUniformRowHeights(true);
}


void QTreeViewNoKbd::keyPressEvent(QKeyEvent *event)
{
    switch (event->key())
    {
    case Qt::Key_Down:
    case Qt::Key_Up:
        break;
    default:
        QTreeView::keyPressEvent(event);
        break;
    }
}


void QTreeViewNoKbd::recursiveRememberNodeState(NodeExpand &ne, QModelIndex root)
{
    int nChild = model()->rowCount(root);


    for (int i = 0; i < nChild; i++)
    {
        QModelIndex index = model()->index(i, 0, root);
        if (this->isExpanded(index))
        {
            NodeExpand n;
            n.nRowNo = i;
            recursiveRememberNodeState(n, index);
            ne.arChildren.push_back(n);
        }
    }
}


void QTreeViewNoKbd::recursiveExpandNode(NodeExpand &ne, QModelIndex root)
{
    QModelIndex index = model()->index(ne.nRowNo, 0, root);
    if (!index.isValid())
    {
        return;
    }


    this->expand(index);
    for (int i = 0; i < ne.arChildren.size(); i++)
    {
        recursiveExpandNode(ne.arChildren[i], index);
    }
}




void QTreeViewNoKbd::startExpandNode()
{
    QModelIndex root = this->rootIndex();
    for (int i = 0; i < m_nodeExpand.arChildren.size(); i++)
    {
        this->recursiveExpandNode(m_nodeExpand.arChildren[i], root);
    }
}


void QTreeViewNoKbd::startRemeberNode()
{
    QModelIndex root = this->rootIndex();
    recursiveRememberNodeState(m_nodeExpand, root);
}