Leaflet和Leaflet MarkerCluster导入不起作用

Question

<ltng:require styles="/resource/leaflet/leaflet.css"/>
    <ltng:require styles="/resource/leafletMarkerCluster/Leaflet.markercluster-1.4.1/dist/MarkerCluster.css"/>
    <ltng:require scripts="{!join(',',$Resource.leaflet +'/leaflet.js' ,$Resource.leafletMarkerCluster +'leaflet.markercluster
.js')}" 
                  afterScriptsLoaded="{!c.jsLoaded}" />

我添加了静态资源，并尝试从aura组件中像这样导入它，但是它没有显示任何内容。有什么想法吗？