QWidget: Must construct a QApplication before a QWidget

[Connailo]

Hi all:
I've got this error in my application when I run in the release mode on Windows( on Ubuntu ,whether in debug or release mode ,there's no problem.And debug mode on Windows is ok). I think this error is related to a C++ library which I used in my application.In the library ,I build a class,which inherit from the QWidget class. And I build another class who is name is XXXmanger ,inherit from the QObject class to manage the widget class .When I try to new the manager class, the app goes wrong.

CHistoryFormManager::CHistoryFormManager(QObject *parent) :
    CbaseFormManager(parent)
{
    d_ptr = new CHistoryFormManagerPrivate;
    d_ptr->q_ptr = this;
}

CHistoryFormManager::CHistoryFormManager(QObject *parent) :
    CbaseFormManager(parent)
{
    d_ptr = new CHistoryFormManagerPrivate;
    d_ptr->q_ptr = this;
}

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This is the construction function of the manager class .

class CHistoryFormManagerPrivate
{
    CHistoryFormManager * q_ptr;
    Q_DECLARE_PUBLIC(CHistoryFormManager)
 
public:
 
    void addItem();
    void deleteItem();
    void openItem();
 
    int                     m_index;
    QMenu                   *m_treeMenu;
    QMenu                   *m_itemMenu;
    QAction                 *m_addFormAction;
    QAction                 *m_deleteFormAction;
    QAction                 *m_openItemAction;
    QStandardItem           *m_item;
    QWidget                 *m_widget;
    QTreeView               *m_treePro;
 
    QList<CHistoryForm *>               m_formList;
    QList<QStandardItem *>              m_newedItemList;
    QMap<QStandardItem*,CHistoryForm*>  m_map;
 
private:
 
    void createTreeMenu(QWidget * parent);   // create tree Menu
    void createItemMenu(QWidget * parent);   // create Item Menu
 
    void createItemAction(QWidget * parent);
    void createTreeAction(QWidget * parent);
};

class CHistoryFormManagerPrivate
{
    CHistoryFormManager * q_ptr;
    Q_DECLARE_PUBLIC(CHistoryFormManager)

public:

    void addItem();
    void deleteItem();
    void openItem();

    int                     m_index;
    QMenu                   *m_treeMenu;
    QMenu                   *m_itemMenu;
    QAction                 *m_addFormAction;
    QAction                 *m_deleteFormAction;
    QAction                 *m_openItemAction;
    QStandardItem           *m_item;
    QWidget                 *m_widget;
    QTreeView               *m_treePro;

    QList<CHistoryForm *>               m_formList;
    QList<QStandardItem *>              m_newedItemList;
    QMap<QStandardItem*,CHistoryForm*>  m_map;

private:

    void createTreeMenu(QWidget * parent);   // create tree Menu
    void createItemMenu(QWidget * parent);   // create Item Menu

    void createItemAction(QWidget * parent);
    void createTreeAction(QWidget * parent);
};

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This is the private class of the manager class.
Please help. Thanks.