Qt5 COM Interface ITextInputPanel in windows doesn't work while fine in Qt4.7 (Touch Event)

[ninon.lafourcade]

Hello,
'm using the COM Interface ITextInputPanel (windows) in Qt4 (4.7.4) to display the OS Virtual Keyboard on touch event and it works fine.
But when I use Qt5 (5.3.2), windows refuse to display the keyboard.

Here the code.

MyDlg.h :

@
class CMyDlg : public QDialog
{
Q_OBJECT
protected:

ITextInputPanel* m_piTextInputPanel;
QLineEdit* m_pLineEdit;

public:
CDlgSelConfig(QWidget* parent = NULL);
~CDlgSelConfig();

virtual bool eventFilter(QObject *obj, QEvent *event);

protected slots:
void OnAccepted();

protected:
void _SetupUI();
};
@

@
CMyDlg::CMyDlg(QWidget* parent)
: QDialog(parent)
, m_piTextInputPanel(nullptr)
, m_pLineEdit(nullptr)
{
_SetupUI();
}

//--------------------------------------------------------------
CMyDlg::~CMyDlg()
{
if (m_piTextInputPanel != nullptr)
m_piTextInputPanel->Release();
}

//--------------------------------------------------------------
void CMyDlg::_SetupUI()
{
// cree la fentre
setObjectName(QString::fromUtf8("DlgSelConfig"));
resize(400, 311);
setMinimumSize(QSize(400, 100));
setWindowFlags(windowFlags()&(~Qt::WindowContextHelpButtonHint));

setWindowTitle(DLLRES_sLoadQString(IDS_CW_TITRE_SELPARAMETRAGE));

QGridLayout* pGridLayout=new QGridLayout(this);
QVBoxLayout* pVerticalLayout=new QVBoxLayout();

if( SUCCEEDED(CoCreateInstance( CLSID_TextInputPanel, nullptr, CLSCTX_INPROC, IID_ITextInputPanel, (void **) &m_piTextInputPanel)))
{

m_pLineEdit = new QLineEdit(this);
pVerticalLayout->addWidget(m_pLineEdit);

m_pLineEdit->installEventFilter(this);
m_pLineEdit->setAttribute(Qt::WA_NativeWindow);
m_pLineEdit->setAttribute(Qt::WA_AcceptTouchEvents);

HWND hWnd = (HWND)m_pLineEdit->winId();

//Attach the windows
XDBG(HRESULT hr = )m_piTextInputPanel->put_AttachedEditWindow(hWnd);
XASSERT(SUCCEEDED(hr));

XDBG(hr = )m_piTextInputPanel->put_InPlaceVisibleOnFocus(FALSE);
XASSERT(SUCCEEDED(hr));

XDBG(hr = )m_piTextInputPanel->put_DefaultInPlaceState(InPlaceState_Expanded);
XASSERT(SUCCEEDED(hr));
}
QObject::connect(pButtonBox, SIGNAL(rejected()), this, SLOT(reject()));
QObject::connect(pButtonBox, SIGNAL(accepted()), this, SLOT(OnAccepted()));
}

//--------------------------------------------------------------
void CDlgSelConfig::OnAccepted()
{
done(QDialog::Accepted);
}

//-------------------------------------------------------------------
bool CDlgSelConfig::eventFilter(QObject *pclSrc, QEvent *pclEvent)
{
if ((pclEvent->type()==QEvent::TouchBegin) && (pclSrc==m_pLineEdit))
{

XDBG(HRESULT hr = )m_piTextInputPanel->SetInPlaceVisibility(TRUE);
//hr=E_FAIL in Qt 5.3.2
}

return __super::eventFilter(pclSrc, pclEvent);
}
@

Any idea why ?

Thank you in advance.