L.esri.featureLayer's maxZoom/minZoom

[shawnmgoulet]

Describe the bug

In this sample, a maxZoom and minZoom are set on a L.esri.featureLayer. The issue is that, after the initial zoom into and out of the maxZoom/minZoom range, the L.icons do not disappear and remain on the map.

Reproduction

A repro Codepen is available here: https://codepen.io/shawnmgoulet/pen/xbKNwrM.

1. Add Leaflet esri-leaflet via CDN
2. Add a L.esri.featureLayer using a point feature service, with maxZoom and minZoom properties and a pointToLayer function that returns an L.marker using a L.icon to represent point features.
3. Zoom to within the maxZoom and minZoom zoom levels, back out of the range, then back into the range and back out again. At this point, you will see L.icons still visible on the map.

Logs

System Info

Leaflet version: 1.9.4 | Esri Leaflet version: 3.0.13

Additional Information

No response

[gavinr-maps]

Thanks for logging this @shawnmgoulet. I am seeing the issue in your example Codepen, but I created a simple sample with the USA Cities service, and I cannot get the issue to happen here: https://jsbin.com/gimaxag/1/edit?html,output

I'll do some more research to try to see what specifically is causing this issue.

[gavinr-maps]

I have validated that this issue happens even without the image symbol or the popups. Here's the simplest replication case I can find:

https://jsbin.com/wotodul/1/edit?html,output

1. Click the zoom-in button 4 times
2. After the points start loading, click the zoom out button
   • Expected: No points showing on the map
   • Actual: sometimes some of the points are still showing on the map:

This seems to happen with feature services with lots of points, and does not happen on feature services with few points. Because of this, my current hypothesis is that if you zoom out so Esri Leaflet tries to hide the layer as they layer is still loading, sometimes the layer will not get hidden properly. Services with lots of data take longer to load so it's easier to get into this situation in situations with lots of data. I need to jump into the code to try to validate this.

[gavinr-maps]

If I remove this code:

esri-leaflet/src/Layers/FeatureLayer/FeatureManager.js

Lines 531 to 537 in e827880

	for (var i in this._cells) {
	var coords = this._cells[i].coords;
	var key = this._cacheKey(coords);
	if (this._cache[key]) {
	this.addLayers(this._cache[key]);
	}
	}

... the issue does not happen. I am not saying this is the solution to the bug since removing that code probably causes issues with other things, but it's a good data point on the root cause.