Latest Contributions by DavidWillis

Aha!  Found the problem - actually had nothing to do with the code (at least not directly).  Someone slipped a non-printing character into one of the database entries, back in 1999 - that was causing my json parser to terminate unexpectedly, and so the map never got any data to populate... One I added a filter to take out the extraneous characters, works perfectly! Dave ... View more

Steve,   Here's my javascript listing (it's not on the production site yet): dojo.require("dijit.layout.BorderContainer");             dojo.require("dijit.layout.ContentPane");             dojo.require("esri.map");             dojo.require("esri.dijit.Popup");             dojo.require("extras.ClusterLayer");                                var map, clusterlayer;             function init() {                 var popupOptions = {                     "markerSymbol": new esri.symbol.SimpleMarkerSymbol("circle", 20, null, new dojo.Color([0, 0, 0, 0.25])),                     "marginLeft": "20",                     "marginTop": "20"                 };                 var popup = new esri.dijit.Popup(popupOptions, dojo.create("div"));                 map = new esri.Map("map", {infoWindow: popup});                 var basemap = new esri.layers.ArcGISTiledMapServiceLayer("http://services.arcgisonline.com/ArcGIS/rest/services/Ocean_Basemap/MapServer");                 map.addLayer(basemap);                                 dojo.connect(map, 'onLoad', function(theMap) {                     //resize the map when the browser resizes                     dojo.connect(dijit.byId('map', 'resize', map,map.resize));                     dojo.style(dojo.query("a.action.zoomTo")[0], "display", "none");                     var markers = <%=getmarkers%>;                     addClusters(markers);                                     });             }    function readData(){               var m = <%=getmarkers%>;           //getmarkers is a json file with location and description data                    }                       function addClusters(resp) {                 var markerInfo = {};                 var wgs = new esri.SpatialReference({ "wkid": 4326 });                 //console.log("Add marker info");                 markerInfo.data = dojo.map(resp, function(p) {                     var latlng = new esri.geometry.Point(parseFloat(p.lat), parseFloat(p.lng), wgs);                     var webMercator = esri.geometry.geographicToWebMercator(latlng);                     var attributes = {                         "Victim": p.Victim,                         "Description": p.Description,                         "Date": p.Date                     };                 return { "x": webMercator.x, "y": webMercator.y, "attributes": attributes };                 });                 // popupTemplate to work with attributes specific to this dataset                 var popupTemplate = esri.dijit.PopupTemplate({                     "title": "", "fieldInfos": [                         { "fieldName": "Victim", visible: true },                         { "fieldName": "Description", visible: true },                         { "fieldName": "Date", visible: true }                     ]                 });                 // cluster layer that uses OpenLayers style clustering                 clusterLayer = new extras.ClusterLayer({                     "data": markerInfo.data,                     "distance": 100,                     "id": "clusters",                     "labelColor": "#fff",                     "labelOffset": 10,                     "resolution": map.extent.getWidth() / map.width,                     "singleColor": "#888",                     "singleTemplate": popupTemplate                 });                 var defaultSym = new esri.symbol.SimpleMarkerSymbol().setSize(4);                 var renderer = new esri.renderer.ClassBreaksRenderer(defaultSym, "clusterCount");                 var blue = new esri.symbol.PictureMarkerSymbol("http://static.arcgis.com/images/Symbols/Shapes/BluePin1LargeB.png", 32, 32).setOffset(0, 15);                 var green = new esri.symbol.PictureMarkerSymbol("http://static.arcgis.com/images/Symbols/Shapes/GreenPin1LargeB.png", 64, 64).setOffset(0, 15);                 var red = new esri.symbol.PictureMarkerSymbol("http://static.arcgis.com/images/Symbols/Shapes/RedPin1LargeB.png", 72, 72).setOffset(0, 15);                 renderer.addBreak(0, 2, blue);                 renderer.addBreak(2, 201, green);                 renderer.addBreak(200, 10001, red);     clusterLayer.setRenderer(renderer);                 map.addLayer(clusterLayer);                 // close the info window when the map is clicked                 dojo.connect(map, "onClick", cleanUp);                 // close the info window when esc is pressed                 dojo.connect(map, "onKeyDown", function(e) {                     if ( e.keyCode == 27 ) {                         cleanUp();                     }                 });             }             function cleanUp() {                 map.infoWindow.hide();                 clusterLayer.clearSingles();             }             function error(err) {                 console.log("something failed: ", err);             }             // show cluster extents             function showExtents() {                 var extents = new esri.layers.GraphicsLayer();                 var sym = new esri.symbol.SimpleFillSymbol().setColor(new dojo.Color([205,193,197,0.5]));                 dojo.forEach(clusterLayer._clusters, function(c) {                     var e = c.attributes.extent;                     extents.add(new esri.Graphic(new esri.geometry.Extent(e[0], e[1], e[2], e[3]), sym));                 }, this);                 map.addLayer(extents, 0);             }                dojo.ready(init); As for the 4600 cutoff, I'm using a query from our database to populate the data - using a time range I can control the number of points rendered.  The page works fine with 4583 points.  When the query returns 4634, I get a blank screen, so the cutoff is somewhere right around 4600 - just not sure why... Thanks! Dave ... View more

I have a similar problem, in that I have just over 5000 points to plot on a map of the world - I am clustering them, though (using the code from the point clustering example in the JavaScript API).  My issue is that it works just fine, up until 4600 points - any more, and the map simply doesn't draw.  Any ideas as to why that might be? ... View more