$self->CanvasBind('<B1-Motion>' => [\&_drawEdgeEvent, $x, $y, $line, $res[0], $res[1]]);
$self->CanvasBind('<ButtonRelease-1>' => \&_drawEdgeEventFinish);
$self->bind("Node", '<Any-Enter>' => \&_enterNode);
$self->bind("Node", '<Any-Leave>' => \&_leaveNode);