绘制后无法 select 多边形

Can't select polygon after drawing it

我正在尝试以交互方式在地图上绘制单独样式的多边形。绘图效果很好,但我似乎无法 select 绘制的多边形来修改它们。我怀疑我对他们实际被吸引到哪里感到困惑:

var drawLayer = new ol.layer.Vector({
     source: new ol.source.Vector() 
     });

map.addLayer( drawLayer );                                      

var select = new ol.interaction.Select();

map.addInteraction( new ol.interaction.Modify({
            features: select.getFeatures()
            }); 

map.addInteraction( draw = new ol.interaction.Draw({    
            source: drawLayer.getSource(),
            type: "Polygon" 
            }); 

draw.on('drawend', function( e ) {
        var sty = new ol.style.Style( {                                 
            fill: new ol.style.Fill( { color: newCol } )
            });
        e.feature.setStyle( sty );
        });

事实证明,在 select 激活之前,您需要通过扩展交互默认值来添加交互。仅使用 map.addInteraction() 添加它是必要的,但还不够。

    featureSelect=new ol.interaction.Select();  

    map=new ol.Map( {
            interactions: ol.interaction.defaults().extend([featureSelect]),    
             //...  
           });