简介
在之前的教程中,您学习了如何将 KML 和 GeoJSON 地图项添加到地图,以及如何添加标记的聚类。但是,如果您想在同一个地图中添加多个这样的图层,然后单独获取每个图层的点击事件,该怎么操作呢?
添加多个聚类、KML 和 GeoJSON 图层
该库包含 Manager
对象,可帮助管理多种类型的图层的点击事件。因此,在设置图层之前,您需要先将这些图层实例化并传入您的 GoogleMap
:
val markerManager = MarkerManager(map)
val groundOverlayManager = GroundOverlayManager(map!!)
val polygonManager = PolygonManager(map)
val polylineManager = PolylineManager(map)
MarkerManager markerManager = new MarkerManager(map);
GroundOverlayManager groundOverlayManager = new GroundOverlayManager(map);
PolygonManager polygonManager = new PolygonManager(map);
PolylineManager polylineManager = new PolylineManager(map);
接下来,在设置其他图层时,您可以将这些管理器类传递到相应图层的构造函数中:
val clusterManager =
ClusterManager<MyItem>(context, map, markerManager)
val geoJsonLineLayer = GeoJsonLayer(
map,
R.raw.geojson_file,
context,
markerManager,
polygonManager,
polylineManager,
groundOverlayManager
)
val kmlPolylineLayer = KmlLayer(
map,
R.raw.kml_file,
context,
markerManager,
polygonManager,
polylineManager,
groundOverlayManager,
null
)
ClusterManager<MyItem> clusterManager = new ClusterManager<>(context, map, markerManager);
GeoJsonLayer geoJsonLineLayer = new GeoJsonLayer(map, R.raw.geojson_file, context, markerManager, polygonManager, polylineManager, groundOverlayManager);
KmlLayer kmlPolylineLayer = new KmlLayer(map, R.raw.kml_file, context, markerManager, polygonManager, polylineManager, groundOverlayManager, null);
添加您自己的地图项
如果除了这些图层,您还想添加自己的标记、地面叠加层、多段线或多边形,请创建自己的 Collection
,然后使用 Managers
添加相应地图项,而不是直接将其添加到 GoogleMap
对象中。添加新标记的示例如下:
val markerCollection =
markerManager.newCollection()
markerCollection.addMarker(
MarkerOptions()
.position(LatLng(51.150000, -0.150032))
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE))
.title("Unclustered marker")
)
MarkerManager.Collection markerCollection = markerManager.newCollection();
markerCollection.addMarker(new MarkerOptions()
.position(new LatLng(51.150000, -0.150032))
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE))
.title("Unclustered marker"));
处理点击事件
对于聚类、KML 和 GeoJSON,只要在您正在设置的图层的构造函数中传入 Manager
类,点击监听器即可正常运行。以下示例展示了如何为 KML 图层设置点击监听器:
kmlPolylineLayer.addLayerToMap()
kmlPolylineLayer.setOnFeatureClickListener { feature: Feature ->
Toast.makeText(context,
"KML polyline clicked: ${feature.getProperty("name")}",
Toast.LENGTH_SHORT
).show()
}
kmlPolylineLayer.addLayerToMap();
kmlPolylineLayer.setOnFeatureClickListener(feature -> Toast.makeText(context,
"KML polyline clicked: " + feature.getProperty("name"),
Toast.LENGTH_SHORT).show());
当您添加自己的标记、地面叠加层、多段线或多边形时,请务必确保向这些 Collection
对象添加点击监听器。以下示例展示了如何在 markerCollection
上设置标记点击监听器:
markerCollection.setOnMarkerClickListener { marker: Marker ->
Toast.makeText(
context,
"Marker clicked: ${marker.title}",
Toast.LENGTH_SHORT
).show()
false
}
markerCollection.setOnMarkerClickListener(marker -> { Toast.makeText(context,
"Marker clicked: " + marker.getTitle(),
Toast.LENGTH_SHORT).show();
return false;
});
观摩演示版应用
如需查看添加多个图层的示例,请参见实用程序库附带的演示版应用中的 MultiLayerDemoActivity
。设置指南介绍了如何运行演示版应用。