Load geoJson in MapBox for editing with Leaflet.Draw - leaflet

I try to load geoJson data in Mapbox and edit it with the plugin Leaflet.Draw
Here is an example : fiddle
var featureGroup = L.featureGroup().addTo(map);
var geojson = {
"type": "FeatureCollection",
"features": [ ........... ]
}
L.geoJson(geojson).addTo(featureGroup);
When i click to the edit button, i have an error :
Uncaught TypeError: Cannot read property 'enable' of undefined
Object seems to be editable but i can't modify it.
What is the correct way to add geojson object in mapbox draw layer ?

I have found the solution :
L.geoJson(geojson, {
onEachFeature: function (feature, layer) {
featureGroup.addLayer(layer);
}
});

Here is working example using CoffeeScript:
drawnItems = new L.FeatureGroup()
map.addLayer drawnItems
layers = L.geoJson geojson
layers.eachLayer (layer) => drawnItems.addLayer layer

I had to do the following to get mine to work (in addition to the above answers):
L.geoJson(geojson, {
onEachFeature: function (feature, layer) {
if (layer.getLayers) {
layer.getLayers().forEach(function (l) {
featureGroup.addLayer(l);
})
} else {
featureGroup.addLayer(layer);
}
}
});
This was for a geojson that was a "Feature" type.

Related

Displaying styles stored in a GeoJson File and making lines appear as lines instead of markers

I've been trying to get Leaflet to display a geojson file using the styles described in the geojson file, and I can't get it to work. The geojson below shows that I've got styles in there - OGR style pen etc, but I've tried extracting them using style function(styles) {return {colour : data.properties.pen}}, but it gives me an error on the console - but not enough errors to match the number of layers - so I can understand that some layers may not have a "pen" property, but none of the layers are coming up with the any differences.
"features": [
{ "type": "Feature", "properties": { "Layer": "Buildings", "SubClasses": "AcDbEntity:AcDb2dPolyline", "EntityHandle": "2ABF", "OGR_STYLE": "PEN(c:#ff7f00,p:"1.2g 0.72g 0.12g 0.72g")" }, "geometry": { "type": "LineString", "coordinates": [ [ -1.386274792183286, 54.907452998026585, 0.0 ], [ -1.386201193400163,
In fact, as the above geojson shows, it's actually a geometry - but all that's showing up is a marker, which is my second problem. Can anyone point me to some example codes or anything which may help me?
$.getJSON(address, function(data) {
//add GeoJSON layer to the map once the file is loaded
layer[i] = L.geoJson(data, {style: function(styles) {
return {color: data.properties.pen,
weight: data.properites.weight
};
onEachFeature: onEachFeature
}
}).addTo(map);
Thanks.
Change your code to:
function onEachFeature(feature, layer) {
if (feature.properties && layer instanceof L.Path) {
layer.setStyle({
color: feature.properties.pen,
weight: feature.properites.weight
});
}
}
$.getJSON(address, function(data) {
//add GeoJSON layer to the map once the file is loaded
layer[i] = L.geoJson(data, {
onEachFeature: onEachFeature
}).addTo(map);
});
Leaflet GeoJson Tutorial

Leaflet Draw and Leaflet Snap with geojson polygon layers

I'm trying to enable snapping (using Leaflet Snap)in a Leaflet application I'm creating. I'm using Leaflet Draw. Existing layers are read in from a database in geojson. I add these to the guideLayers and I add newly created features there too. It's not working. Has anyone successfully been able to create something like this? That is, been able to create a new polygon and snap to existing polygons in leaflet (geojson layers)? Thanks Dan.
Add geojson to guideLayers code:
function renderLta(_ltas,ltaLayerName) {
L.geoJSON([_ltas.geoJson], {
name:_ltas.id,
areaName:_ltas.localThreatAreaName,
areaDescription:_ltas.localThreatAreaDescription,
style: function (feature) {
return _getLtaStyle(1);
},
onEachFeature: function onEachFeature(feature, layer) {
ltaLayerName.addLayer(layer);
guideLayers.push(layer);
layer.on('click', function(e) {
if(selectedFeature) {
selectedFeature.editing.disable();
// Has there been a change? Does the user need to save?
// get layer again and redraw
drawnItems.removeLayer(selectedFeature);
selectedFeature.addTo(map_lta);
}
selectedFeature = e.target;
e.target.editing.enable();
drawnItems.addLayer(e.target);
});
}
});
ltaLayerName.addTo(map);
Add new layer/data to guideLayers code:
map.on(L.Draw.Event.CREATED, function(event) {
var layer = event.layer;
var content = getPopupContent(layer);
if (content !== null) {
layer.bindPopup(content);
}
drawnItems.addLayer(layer);
guideLayers.push(layer);
});
DrawControl Code:
var drawControl = new L.Control.Draw({
edit: {
featureGroup: drawnItems,
poly : {
allowIntersection : false
}
},
draw: {
polyline: false,
polygon : { showArea: true, allowIntersection : false, guideLayers: guideLayers, snapDistance: 500 },
circle: false,
rectangle: false,
marker: false,
circlemarker: false
}
});
map_lta.addControl(drawControl);
drawControl.setDrawingOptions({
polygon: { guideLayers: guideLayers, snapDistance: 50 },
});
You can use the following library to draw and snap https://www.npmjs.com/package/#geoman-io/leaflet-geoman-free packages
and for more functionalities which are not present in above mentioned package you can use this one especially for polylines
https://www.npmjs.com/package/leaflet-linestring-editor
I gave up on the leaflet draw library and snap, and used leaflet-geoman library instead. Snapping working perfectly.

in-place Update Leaflet GeoJSON feature

I was hoping that GeoJSON.addData() would return the newly created subLayer of the GeoJSON object, but it does not. Why Do I need something like this?
(currently using Leaflet 1.0Beta2)
I am using Leaflet GeoJson to show live data in a GeoJSON (point, line, polygon). It is a CRUD interface (Create, Update and Delete). I receive WebSocket messages with GeoJSON data, each one with a GUID.
I the case of a CREATE I just do a GeoJSon.AddData() to the appropriate layer.
But for the UPDATE and DELETE I want a handle for the layer that was added to the GeoJSON so that I can update its location, or update the Geometry. addData is not giving me this handle. And it is really hard to get it from onEachFeature() or from pointToLayer()
Currently, I do have a way that works but ugly. I have to do is search the entire layer with GeoJSon.eachLayer(fn)
whenever an update or delete occurs. It seems a bit expensive.
{even if Leaflet is not truly engineered for this live r/t display of data, it is working, and it seems sad if you cannot use it for watching a lot of sensor data, IoT) as we are doing.
this.delete = function (layerName, feature) {
if (!(layerName in self.myLayers)) {
alert("live.display: Missing Layer: " + layerName);
return;
}
var layerInfo = Live.myLayers[layerName];
var base = layerInfo.layer;
var id = feature.properties.objectID;
this.find(layerName, id, function (layer) {
this.removeLayer(layer);
Tools.debug(16, "live.delete:", "killed object: " + id);
});
}
this.find = function (layerName, id, action) {
var base = Live.myLayers[layerName].layer;
base.eachLayer(function (feature) {
if (!("objectID" in feature.feature.properties)) { return; }
var objectID = feature.feature.properties.objectID;
if (objectID == id) {
action.call(base, feature);
}
});
}
Instead (or in parallel) of "merging" all created GeoJSON features into a single Leaflet GeoJSON layer group (which you do with addData), why not creating first each feature in its own Leaflet GeoJSON layer, so that it gives you the handle you are looking for (then you could simply record this handle in an object / mapping with the key being your objectID for example)?
If desired, you could even still merge the individual layers into your single GeoJSON layer group after that.
var myGeoJsonLayerGroup = L.geoJson().addTo(map);
var myFeaturesMap = {};
function addNewFeatureToGeoJsonLayerGroup(newGeoJsonData) {
var newGeoJSONfeature = L.geoJson(newGeoJsonData);
myFeaturesMap[newGeoJsonData.properties.objectID] = newGeoJSONfeature;
myGeoJsonLayerGroup.addLayer(newGeoJSONfeature);
}
function updateFeature(updatedGeoJsonData) {
var updatedFeature = myFeaturesMap[updatedGeoJsonData.properties.objectID];
updatedFeature.clearLayers(); // Remove the previously created layer.
updatedFeature.addData(updatedGeoJsonData); // Replace it by the new data.
}
function deleteFeature(deletedGeoJsonData) {
var deletedFeature = myFeaturesMap[deletedGeoJsonData.properties.objectID];
myGeoJsonLayerGroup.removeLayer(deletedFeature);
}
Demo (not using GeoJSON): http://jsfiddle.net/ve2huzxw/94/
EDIT:
A slightly more simple solution would be to store the reference to each individual layer through the onEachFeature function of the GeoJSON layer group:
var myFeaturesMap = {};
var myGeoJsonLayerGroup = L.geoJson({
onEachFeature: function (feature, layer) {
myFeaturesMap[feature.properties.objectID] = layer;
}
}).addTo(map);
function addNewFeatureToGeoJsonLayerGroup(newGeoJsonData) {
myGeoJsonLayerGroup.addData(newGeoJsonData);
}
function updateFeature(updatedGeoJsonData) {
deleteFeature(updatedGeoJsonData); // Remove the previously created layer.
addNewFeatureToGeoJsonLayerGroup(updatedGeoJsonData); // Replace it by the new data.
}
function deleteFeature(deletedGeoJsonData) {
var deletedFeature = myFeaturesMap[deletedGeoJsonData.properties.objectID];
myGeoJsonLayerGroup.removeLayer(deletedFeature);
}
If you want to store references to the actual layers being created, you can access them from the layeradd event on your L.GeoJSON instance:
var geojson = new L.GeoJSON().on(
'layeradd', function (e) {
console.log(e.layer);
}
).addTo(map);
// This addData call will fire the handler above twice
// because it adds two features.
geojson.addData({
"type": "FeatureCollection",
"features": [{
"type": "Feature",
"properties": {},
"geometry": {
"type": "Point",
"coordinates": [90, 0]
}
}, {
"type": "Feature",
"properties": {},
"geometry": {
"type": "Point",
"coordinates": [-90, 0]
}
}]
});
If someone still looking for another short method to update GeoJSON, you can try something like this,
//function to clear the previous geojson feature
function clearMap() {
map.eachLayer(function(layer){
if(layer.myTag && layer.myTag === 'previousLayer'){
lmap.removeLayer(layer);
}
});
}
function geojsonUpdate(geojsonData){
var geojsonLayer = L.geoJson(geojsonData, {
onEachFeature: function (feature, layer) {
layer.myTag = 'previousLayer'
);
},
});
geojsonLayer.addTo(lmap);
lmap.fitBounds(geojsonLayer.getBounds());
}
//function call
clearMap();
geojsonUpdate(data);

geojson ignored when using mapbox

why does mapbox ignore my geoJson marker-symbol, marker-color, and marker-size? if for whatever reason it ignores, how do you set either?
sample geoJson:
"properties": {
"id": 578202,
"name": "University of North Carolina at Charlotte",
"marker-symbol": "marker",
"marker-color": "#ff8888",
"marker-size": "small",
"description": 1
}
script:
$.getJSON(url, function(data) {
var geojson = L.geoJson(data, {
onEachFeature: function(feature, layer) {
var popupContent = feature.properties.name +'project(s)';
layer.bindPopup(popupContent, {
closeButton: true,
minWidth: 225
});
}
});
var map = L.mapbox.map('map', '', {
attributionControl: false
});
geojson.addTo(map);
});
That's happening because L.GeoJSON doesn't automaticly know that you want to set the marker options, so if it encounters a Point feature, it simply adds a default marker. If you want to do something special with point features, you can use the pointToLayer function of L.GeoJSON, check the following example:
var geoJsonLayer = L.geoJson(geoJson, {
pointToLayer: function (feature, latLng) {
return L.marker(latLng, {
icon: L.mapbox.marker.icon(feature.properties)
});
}
}).addTo(map);
The only problem with this is that it also adds all the other properties as options of the markericon. Personally i would write some logic so that only the relevant properties get added to the icon options.
Here's a working example on Plunker: http://plnkr.co/edit/3OJPXxOYdzX8mSnjEb90?p=preview
As tmcw pointed out in the comments (see below): you could use L.mapbox.featureLayer, it does exactly what you're trying to accomplish with L.GeoJSON without having to resort to the pointToLayer method i described above and it only uses the appropriate properties. It can even load your data for you so you can do away with jQuery's $.getJSON. Win/win situation if you ask me. You can simply do the following and you're set:
L.mapbox.featureLayer(url).addTo(map);
Here's the working example of this on Plunker: http://plnkr.co/edit/Og6tuYDIkTX7ftedoR3C?p=preview

Leaflet elevation profiles with multiple GeoJSON features

I have a map which loads a GeoJSON containing two features (lines). I would like to use Leaflet Elevation plugin to display an elevation profile for each of those lines. The problem with my code is that when I click a feature, there is no data added to the elevation profile.
var map = L.map('map').setView([44.635, 22.653], 11);
var osm = L.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png').addTo(map);
function addData(e) {
var el = L.control.elevation();
el.addData(e);
map.addControl(el);
}
function onEachFeature(feature, layer) {
layer.on({
click: addData
});
}
var trails = new L.GeoJSON.AJAX('https://googledrive.com/host/0B55_4P6vMjhITEU4Ym9iVG8yZUU/map.geojson', {
onEachFeature: onEachFeature
}).addTo(map);
Here's a JSFiddle of my work: http://jsfiddle.net/pufanalexandru/eaok0Lnz/3/
To anyone who might be interested, I think I found a way to achieve this:
var trails = new L.GeoJSON.AJAX('https://googledrive.com/host/0B55_4P6vMjhITEU4Ym9iVG8yZUU/map.geojson', {
onEachFeature: function onEachFeature(feature, layer) {
layer.on({
click: function () {
el.clear();
el.addData(feature);
}
});
}
}).addTo(map);