how to wait a new web page opened by javascript is ready?

#include <ie.au3>
$oIE = _IECreate ("https://mypage:7493/idem/suite/login.do")
 
$oFrame = _IEFrameGetCollection($oIE, 0) ; first frame (frame 0)
 
$oForm = _IEFormGetObjByName ($oFrame, "basicLogonForm"); this form is inside the frame
 
$oQuery1 = _IEFormElementGetObjByName ($oForm, "username") ; first field inside the form
$oQuery2 = _IEFormElementGetObjByName ($oForm, "userpassword") ; second field inside the form
 
$uname="MyUsername"
$pwd="MyPassword"
 
_IEFormElementSetValue ($oQuery1,$uname) ; input username
_IEFormElementSetValue ($oQuery2,$pwd) ; input password
 
$oButton=_IEGetObjById($oFrame,"button") ; reference to button
 
_IEAction ($oButton, "click") ; click on button
 
_IELoadWait($oIE) ; <=== here, the script goes on without waiting
                  ; and following statements give error
 
; Sleep ( 10000 ) ; if I force waiting, the script give no error
                  ; because the new page has time to load itself
 
Local $oFrame = _IEFrameGetObjByName($oIE, "main-frame") ; new frame in the new page
 
$oForm = _IEFormGetObjByName ($oFrame, "SimpleSearchfrm"); new form in new page
 
$oQuery1 = _IEFormElementGetObjByName ($oForm, "simplesearchquery")
 
_IEFormElementSetValue ($oQuery1,"nametosearch")
 
.... etc ....