TopAbs_VERTEX selection mode doesn't work

hi i use this code  :

mContext->Deactivate();

mContext->Activate(AIS_Shape::SelectionMode(TopAbs_EDGE));

for changing the selection mode , and it works for all these modes : 

TopAbs_COMPOUND,
TopAbs_COMPSOLID,
TopAbs_SOLID,
TopAbs_SHELL,
TopAbs_FACE,
TopAbs_WIRE,
TopAbs_EDGE,
TopAbs_SHAPE

and they are highlighted at  //mContext->MoveTo(point.x, point.y, mView, true);

except for vertex selection TopAbs_VERTEX,

// mContext->Activate(AIS_Shape::SelectionMode(TopAbs_VERTEX ));  // doesn't work

or maybe it works and but can't see vertices highlighted  at  //mContext->MoveTo(point.x, point.y, mView, true);

what am i doing wrong ? and how can i get vertices highlighted so i can select it !!

my OS is win7-64bit

occt 7.3.0 _ shared dlls _ 32 bit debug build

MSVC 2013