HasDetected never returning anything

Hi, I have OC 7.2 and a little app drawing the MakeBottle example and few extra primitive for testing. Now I'd like to detect a shape when the mouse moves around. Under my MouseMove function, I try this method but it's never true.

void wxViewOC::mouseMoved(wxMouseEvent& event)

{

if (mContext->HasDetected()){
     wxMessageBox("HasDetected");//the code never reach this part
 }

}

Am I missing a setting or something?