loading vector layer in OL3 with and without ajax

Question

I am trying to use OL3 for loading a vector layer from a geoserver using the following JavaScript code.

<!DOCTYPE html>
<html lang="en">
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no, width=device-width">
<script src="https://code.jquery.com/jquery-1.11.2.min.js"></script>
<link rel="stylesheet" href="http://openlayers.org/en/v3.8.2/css/ol.css" />
<link rel="stylesheet" href="ol3-layerswitcher-master/src/ol3-layerswitcher.css" />
</head>
<body>
<div id="map" class='map'></div>
<script src="http://openlayers.org/en/v3.8.2/build/ol.js"></script>
<script src="ol3-layerswitcher-master/src/ol3-layerswitcher.js"></script>
<script>
var geojasonFormat = new ol.format.GeoJSON();

var vectorSource = new ol.source.Vector({
    loader: function(extent, resolution, projection) {
        var url = 'http://bart.nateko.lu.se:8080/geoserver/wfs?&service=wfs&version=1.1.0&request=GetFeature&typeName=Ehsan:nyc_roads&outputFormat=application/json&maxFeatures=100&format_options=callback:loadFeatures';
        // use jsonp: false to prevent jQuery from adding the "callback"
        // parameter to the URL
        $.ajax({url:url,dataType:'jsonp',jsonp:true});
    },
    strategy: ol.loadingstrategy.tile(new ol.tilegrid.createXYZ({
    maxZoom: 19
    }))
});

window.loadFeatures = function(httpOutPut){
    vectorSource.addFeatures(geojsonFormat.readFeatures(response))
    };  


var vectorLayer = new ol.layer.Vector({
                    title:'road layer',
                    source: vectorSource,
                    style: new ol.style.Style({
                        stroke: 'rgba(255,255, 255, 1.0)',
                        width: 2
                    })
                });

var vectorGroup = new ol.layer.Group({
    'title':'vector',
    layers:[vectorLayer]});


var map = new ol.Map({
    target: document.getElementById('map'),
    layers:[
        new ol.layer.Group({
            'title': 'Base maps',
            layers:[ 
                new ol.layer.Tile({
                title: 'base map',
                type: 'base',
                source: new ol.source.MapQuest({layer: 'sat'})
                })
            ],
        }),vectorGroup

    ],
    view: new ol.View({
        center: ol.proj.transform([-74, 40.74], 'EPSG:4326', 'EPSG:3857'),
        zoom: 15    })
});
/*var extent = vectorLayer.getSource().getExtent();
map.getView().fit(extent, map.getSize());*/

var layerSwitcher = new ol.control.LayerSwitcher();
map.addControl(layerSwitcher);

</script>
</body>
</html>

I tried to follow the openlayers WFS example using ajax for loading the features in the vector source, but it is not working.

Additionally, I am wondering if there is a simpler solution for loading a vector layer from a geoserver WFS, something without AJAX. the ol2 seems to be more straight forward.

Answer 1

Your callback is

window.loadFeatures = function(httpOutPut){
    vectorSource.addFeatures(geojsonFormat.readFeatures(response))
    };

If you change httpOutPut to response and your response from the servers is correct, you should probably be ok.

You are not sending the extent/bbox to geoserver, so you might be getting features outside of the extent.

This is the current way to load WFS data in ol3. There has been a recent change to master, so OpenLayers 3.9.0 will contain a simplified way of using WFS and use a new WFS example.

loading vector layer in OL3 with and without ajax

Question

1 answers

solution1
1 2015-09-06 20:13:07

loading vector layer in OL3 with and without ajax

Question

1 answers

solution1 1 2015-09-06 20:13:07

solution1
1 2015-09-06 20:13:07