Click event on polylines from GeoJSON file

CesiumJS
1

I've scoured the docs and examples but can't get this to work. I have a geoJSON file that has a featureCollection:

{
"type": "FeatureCollection",
"crs": { "type": "name", "properties": { "name": "urn:ogc:def:crs:OGC:1.3:CRS84" } },
"features": [
{ "type": "Feature", "properties": { "Name": "Sample name", "Description": "Sample description" }, "geometry": { "type": "MultiLineString", "coordinates": [ [ [ -121.679276, 48.920131, 926.9 ], [ -121.677559, 48.932763, 1010.5 ], [ -121.664513, 48.939528, 1021.7 ], [ -121.654041, 48.944715, 1190.1 ], [ -121.645458, 48.944151, 1219.9 ], [ -121.641853, 48.948886, 1581.4 ], [ -121.643398, 48.951817, 1736.4 ], [ -121.643742, 48.956552, 1942.0 ], [ -121.645115, 48.96106, 1837.6 ], [ -121.646317, 48.967259, 1835.0 ], [ -121.642712, 48.971316, 1881.6 ], [ -121.640995, 48.974471, 2058.3 ], [ -121.648205, 48.97909, 2391.1 ] ] ] } },
[... additional content truncated ...]

Currently I have it displaying on my map and when you click a polyline you get the Cesium UI widget that shows the properties for the line. What I would like is to be able to show some custom UI when you click on one of the lines. But I can't seem to figure out how to listen clicks on these polylines since they were added via Cesium.GeoJsonDataSource.

Thanks for you help!

Bobby

2

If you want to customize the data shown in the built-in Cesium Info Box, you can add a “description” GeoJSON property to your features (note that it expects lowercase “description”, not “Description” as in your example. not sure if there’s a convention for property names)

If you want to display your own independent UI, you could consider checking the “selectedEntity” property on Viewer. (this property is added by “viewerEntityMixin” which I assume you’re already using)

You can also subscribe to changes to that observable property:

Cesium.knockout.getObservable(viewer, ‘selectedEntity’).subscribe(function(entity) {

if (entity !== undefined) {

console.log(entity.id);

}

});

3

Great, thanks Scott!