解决Leaflet.draw中polyline绘制无法结束的问题

/** * @class L.Draw.Polyline4Diy * @aka Draw.Polyline4Diy * @inherits L.Draw.Polyline */L.Draw.Polyline4Diy=L.Draw.Polyline.extend({
statics: {
TYPE: 'polyline4diy'  },
​options: {
allowIntersection: true,
repeatMode: false,
drawError: {
color: '#b00b00',
timeout: 2500    },
icon: newL.DivIcon({
iconSize: newL.Point(8, 8),
className: 'leaflet-div-icon leaflet-editing-icon'    }),
touchIcon: newL.DivIcon({
iconSize: newL.Point(20, 20),
className: 'leaflet-div-icon leaflet-editing-icon leaflet-touch-icon'    }),
guidelineDistance: 20,
maxGuideLineLength: 4000,
shapeOptions: {
stroke: true,
color: '#3388ff',
weight: 4,
opacity: 0.5,
fill: false,
clickable: true    },
metric: true, // Whether to use the metric measurement system or imperialfeet: true, // When not metric, to use feet instead of yards for display.nautic: false, // When not metric, not feet use nautic mile for displayshowLength: true, // Whether to display distance in the tooltipzIndexOffset: 2000, // This should be > than the highest z-index any map layersfactor: 1, // To change distance calculationmaxPoints: 0// Once this number of points are placed, finish shape  },
​// @method initialize(): voidinitialize: function (map, options) {
// if touch, switch to touch iconif (L.Browser.touch) {
this.options.icon=this.options.touchIcon;
    }
​// Need to set this here to ensure the correct message is used.this.options.drawError.message=L.drawLocal.draw.handlers.polyline.error;
​// Merge default drawError options with custom optionsif (options&&options.drawError) {
options.drawError=L.Util.extend({}, this.options.drawError, options.drawError);
    }
​// Save the type so super can fire, need to do this as cannot do this.TYPE :(this.type=L.Draw.Polyline4Diy.TYPE;
​L.Draw.Feature.prototype.initialize.call(this, map, options);
  },
​// calculate if we are currently within close enough distance// of the closing point (first point for shapes, last point for lines)// this is semi-ugly code but the only reliable way i found to get the job done// note: calculating point.distanceTo between mouseDownOrigin and last marker did NOT work_calculateFinishDistance: function (potentialLatLng) {
varlastPtDistance;
if (this._markers.length>0) {
varfinishMarker;
if (this.type===L.Draw.Polyline.TYPE) {
finishMarker=this._markers[this._markers.length-1];
      } elseif (this.type===L.Draw.Polygon.TYPE) {
finishMarker=this._markers[0];
      } else {
returnInfinity;
      }
varlastMarkerPoint=this._map.latLngToContainerPoint(finishMarker.getLatLng()),
potentialMarker=newL.Marker(potentialLatLng, {
icon: this.options.icon,
zIndexOffset: this.options.zIndexOffset*2        });
varpotentialMarkerPint=this._map.latLngToContainerPoint(potentialMarker.getLatLng());
lastPtDistance=lastMarkerPoint.distanceTo(potentialMarkerPint);
    } else {
lastPtDistance=Infinity;
    }
returnlastPtDistance;
  }
});

statics: {
TYPE: 'polyline4diy'  },

// @method initialize(): voidinitialize: function (map, options) {
// if touch, switch to touch iconif (L.Browser.touch) {
this.options.icon=this.options.touchIcon;
    }
​// Need to set this here to ensure the correct message is used.this.options.drawError.message=L.drawLocal.draw.handlers.polyline.error;
​// Merge default drawError options with custom optionsif (options&&options.drawError) {
options.drawError=L.Util.extend({}, this.options.drawError, options.drawError);
    }
​// Save the type so super can fire, need to do this as cannot do this.TYPE :(this.type=L.Draw.Polyline4Diy.TYPE;
​L.Draw.Feature.prototype.initialize.call(this, map, options);
  },

functiondrawLine(){
diyDrawLayers.clearLayers();
newL.Draw.Polyline4Diy(map).enable();
}

// Object created - bind popup to layer, add to feature groupmap.on(L.Draw.Event.CREATED, function(event) {
varlayer=event.layer;
varlayerType=event.layerType;
varcontent=getPopupContent(layer);
if (content!==null) {
layer.bindPopup(content);
      }
if(layerType==L.Draw.Rectangle4Diy.TYPE||layerType==L.Draw.Polyline4Diy.TYPE){
diyDrawLayers.addLayer(layer);
      }else{
drawnItems.addLayer(layer);
      }
  });