OpenLayers 4 – Get All Child Layers in a Layer Group

javascriptopenlayers

How can I get all child layers of a given layer group in Openlayers?

I go as far as establishing that a given layer is in fact a group, but then I get stumped:

// Handle visibility control
$('i').on('click', function() {
    var layername = $(this).closest('li').data('layerid');
    var layer = findBy(map.getLayerGroup(), 'name', layername);
    var flagGroup = layer instanceof ol.layer.Group;
    if (flagGroup) {
       ...
    }
});

Best Answer

childLayers = layer.getLayers()

https://openlayers.org/en/latest/apidoc/ol.layer.Group.html#getLayers

Related Solutions

OpenLayers – How to Get Layer Type in OpenLayers 3?

If anyone gets stuck with identifying a layer's type in OpenLayers 3, there is a more sophisticated JavaScript method to achieve this. As layer objects are created with layer constructors, the native instanceof JavaScript function can be used to check for layer type.

As the identification of a layer type usually gets into an if or switch clause, one could easily check for the presence of the constructor's prototype object in the layer, instead of storing the type as a property on construction.

var groupLyr = new ol.layer.Group();
groupLyr instanceof ol.layer.Group;
//true
groupLyr instanceof ol.layer.Vector;
//false

[GIS] reset style oneach

A solution would be to bind your "click" event listener on the GeoJSON layer group, rather than on each individual child feature layer.

That way, e.target gives you access to the group (so that you can reset the style of that group rather than others), and e.layer gives you the individual child feature layer (so that you can highlight it in particular).

assembly.on("click", onFeatureGroupClick);

function onFeatureGroupClick(e) {
  var group = e.target,
      layer = e.layer;

  group.setStyle(style2);
  layer.setStyle(highlight);
}

Example: http://jsfiddle.net/quu3ykp6/8/

Best Answer

Related Solutions

OpenLayers – How to Get Layer Type in OpenLayers 3?

[GIS] reset style oneach

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