getLayer returns a layer but queryRenderedFeatures given a layer returns empty

[Carpetfizz]

I've added a few layers to the map and now I want to extract some features from it. I've made sure the layer exists by using this call

console.log(this.map.getLayer(focus_key+"-point"));

which prints:

t {id: "8b4bc65b-4f60-43fd-bcde-fa63fa936479-point", metadata: undefined, type: "circle", source: "8b4bc65b-4f60-43fd-bcde-fa63fa936479", sourceLayer: undefined…}

Right after, I want to get all the features in the layer so I'm calling:

console.log(this.map.queryRenderedFeatures({layers: [focus_key+"-point"]}));

This returns an empty array [].

How can it be that the layer exists but querying for a feature in that layer, returns empty?

[peterqliu]

How can it be

It can be, when:

• the layer has no features, or
• the layer has no features within the rendered view, at time of query

Note that queryRenderedFeatures queries for features, not layers.

@Carpetfizz Are you sure that there is a feature from that layer in the current view, when you do the query? a test case would be useful here.

[Carpetfizz]

I see a feature on my map, and the layer.layout.visibility=="visible"

Could it possibly be an async issue?

[jfirebaugh]

@Carpetfizz Can you provide a minimal, self-contained example that demonstrates the issue?

[Carpetfizz]

@jfirebaugh @peterqliu here's a small demo where the bug occurs:

http://codepen.io/anon/pen/XMjPwd?editors=1011

[jfirebaugh]

Adding a layer is an asynchronous operation with respect to queryRenderedFeatures; see the discussion in #4222 and in particular #4222 (comment).