QTreeView三态checkbox代码



/*-----------------------------------

 *

 * Class PermissionTreeView

 *

*-----------------------------------*/

class PermissionTreeView : public QTreeView

{

    Q_OBJECT

public:

    explicit PermissionTreeView(QWidget *parent = 0);

    ~PermissionTreeView();

    void setModel(QStandardItemModel *model);

private:

    void treeItemCheckAllChildRecursion(QStandardItem *item, bool check);

    void treeItemCheckParentRecursion(QStandardItem *item);

    void treeItemCheckChildChanged( QStandardItem *item );

    Qt::CheckState checkSibling(QStandardItem * item);

private slots:

    void treeItemChanged( QStandardItem *item );                            //某一项状态被改变后的处理函数

private:

};

/*-----------------------------------
 *
 * Class PermissionTreeView
 *
*-----------------------------------*/
PermissionTreeView::PermissionTreeView(QWidget *parent) :
    QTreeView(parent)
{
    /*--------------------------
    *
    *--------------------------*/
    setHeaderHidden(true);
}

PermissionTreeView::~PermissionTreeView()
{

}

void PermissionTreeView::setModel(QStandardItemModel *model)
{
    connect(model, SIGNAL(itemChanged(QStandardItem*)), this, SLOT(treeItemChanged(QStandardItem*)));

    QAbstractItemModel *aModel = qobject_cast<QAbstractItemModel *>(model);
    QTreeView::setModel(aModel);
}

void PermissionTreeView::treeItemCheckAllChildRecursion(QStandardItem *item, bool check)
{
    if(item == NULL)
        return;
    int rowCount = item->rowCount();
    for(int i = 0; i < rowCount; ++i)
    {
        QStandardItem* childItems = item->child(i);
        treeItemCheckAllChildRecursion( childItems, check );
    }
    if( item->isCheckable() )
        item->setCheckState( check ? Qt::Checked : Qt::Unchecked );
}

void PermissionTreeView::treeItemCheckParentRecursion(QStandardItem *item)
{
    Qt::CheckState status = checkSibling(item);
    QStandardItem * parent = item->parent();
    if(NULL != parent)
    {
        item->parent()->setCheckState(status);
        treeItemCheckParentRecursion(item->parent());
    }
}


void PermissionTreeView::treeItemCheckChildChanged(QStandardItem *item)
{
    if(NULL == item)
        return;
    Qt::CheckState siblingState = checkSibling(item);
    QStandardItem * parentItem = item->parent();
    if(NULL == parentItem)
        return;
    if(Qt::PartiallyChecked == siblingState)
    {
        if(parentItem->isCheckable() && parentItem->isTristate())
            parentItem->setCheckState(Qt::PartiallyChecked);
    }
    else if(Qt::Checked == siblingState)
    {
        if(parentItem->isCheckable())
            parentItem->setCheckState(Qt::Checked);
    }
    else
    {
        if(parentItem->isCheckable())
            parentItem->setCheckState(Qt::Unchecked);
    }
    treeItemCheckChildChanged(parentItem);
}

Qt::CheckState PermissionTreeView::checkSibling(QStandardItem *item)
{
    //先通过父节点获取兄弟节点
    QStandardItem * parent = item->parent();
    if(NULL == parent)
        return item->checkState();

    int brotherCount = parent->rowCount();
    int checkedCount(0), unCheckedCount(0);
    Qt::CheckState state;
    for(int i = 0; i < brotherCount; ++i)
    {
        QStandardItem* siblingItem = parent->child(i);
        state = siblingItem->checkState();
        if(Qt::PartiallyChecked == state)
            return Qt::PartiallyChecked;
        else if(Qt::Unchecked == state)
            ++unCheckedCount;
        else
            ++checkedCount;
        if(checkedCount>0 && unCheckedCount>0)
            return Qt::PartiallyChecked;
    }
    if(unCheckedCount>0)
        return Qt::Unchecked;
    return Qt::Checked;
}

void PermissionTreeView::treeItemChanged(QStandardItem *item)
{
    if ( item == NULL )
        return ;

    //如果条目是存在复选框的，那么就进行下面的操作
    if ( item->isCheckable ())
    {
        Qt::CheckState state = item->checkState (); //获取当前的选择状态

        //如果条目是三态的，说明可以对子目录进行全选和全不选的设置
        if ( item->isTristate ())
        {
            //非半选状态
            if ( state != Qt::PartiallyChecked )
            {
                //对子目录进行操作
                treeItemCheckAllChildRecursion( item , state == Qt::Checked ? true : false );

                //对父目录进行操作
                treeItemCheckParentRecursion(item);
            }
            else
            {
            }
        }
        //说明是两态的，两态会对父级的三态有影响
        else
        {
            //判断兄弟节点的情况
//            treeItemCheckChildChanged( item );
        }
    }

}