如何在openlayers 3中隐藏/显示线串？

Question

我有两个同时绘制的LineStrings

  var vectorSource = new ol.source.Vector();
  var vectorLayer = new ol.layer.Vector({ source: vectorSource });
  var drawLine = new ol.interaction.Draw({
      source: vectorSource,
      type: 'LineString'
  });


  var vectorSourceHide = new ol.source.Vector();
  var vectorLayerHide = new ol.layer.Vector({ source: vectorSourceHide });
  var drawLineHide = new ol.interaction.Draw({
      source: vectorSourceHide,
      type: 'LineString'
  });

  map.addLayer(vectorLayer);
  map.addLayer(vectorLayerHide);

然后在某些声明中我需要完成绘制第一行并隐藏第二行，然后在另一个声明中我需要再次显示第二行 所以看起来应该是这样的 -

if(true){
drawLine.finishDrawing();
//how to hide drawLineHide ???????   }

if(false){
//how to show drawLineHide ??????? }

如果您知道，请写下如何隐藏/显示此行。