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Leaflet not show EPSG:3857 coordinates

I am totally stuck with my WGS 84 / EPSG:3857 coordinates and display them on Leaflet.
I have Geojson with coordinates.
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [
"6690861",
"682187"
]
},
"properties": {
"id": "908",
"message": "105",
"date": "",
"place": "",
"shape": ""
}
}
Now i want it display on Leaflet. But nothing show up. I search already 5 hours and find something about Proj4. Also no errors showing up.
My script code:
var map = L.map('map').setView([52.2129919, 5.2793703], 8);
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {attribution: 'Map data © OpenStreetMap'}).addTo(map);
// GeoJSON layer (UTM15)
proj4.defs('EPSG:3857');
async function addGeoJson() {
const response = await fetch("geojs.php");
const data = await response.json();
L.geoJson(data).addTo(map);
var layerGroup = L.geoJSON(data, {
onEachFeature: function (feature, layer) {
layer.bindPopup('<h1>'+feature.properties.message+'</h1><p>Datum: '+feature.properties.date+'</p>');
}
}).addTo(map);
}
addGeoJson();
It's for my the first time i work with this coordinates. With lat/long coordinates was don't have problems. And just started with javascript.
Kind regards,

I might be a bit late, but following the documentation of Proj4, I would say that you need to add the crs to your geojson, like so :
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [
"6690861",
"682187"
]
},
"properties": {
"id": "908",
"message": "105",
"date": "",
"place": "",
"shape": ""
},
"crs": {
"type": "name",
"properties": {
"name": "urn:ogc:def:crs:EPSG::3857"
}
}
}
Also, I think it's
L.Proj.geoJson(data).addTo(map);
instead of
L.geoJson(data).addTo(map);
I tried L.geoJson on my code and it didn't show anything contrary to L.Proj.geoJson so it might be your problem here.

Convert javascript to json?

I'm working with leaflets and I've noticed that many examples use a separate js file where a variable is set to a JSON stream.
How would I be able to modify the following example so that it can read off a json file with the geojson and not have the variable declaration in the javascript?
The code looks like this:
<script type="text/javascript">
var geoJsonData = {
"type": "FeatureCollection",
"features": [
{ "type": "Feature", "id":"1", "properties": { "address": "2" }, "geometry": { "type": "Point", "coordinates": [175.2209316333,-37.8210922667 ] } },
{ "type": "Feature", "id":"2", "properties": { "address": "151" }, "geometry": { "type": "Point", "coordinates": [175.2238417833,-37.80975435 ] } },
{ "type": "Feature", "id":"3", "properties": { "address": "21" }, "geometry": { "type": "Point", "coordinates": [175.2169955667,-37.818193 ] } },
{ "type": "Feature", "id":"4", "properties": { "address": "14" }, "geometry": { "type": "Point", "coordinates": [175.2240856667,-37.8216963 ] } },
{ "type": "Feature", "id":"5", "properties": { "address": "38B" }, "geometry": { "type": "Point", "coordinates": [175.2196982333,-37.8188702167 ] } },
{ "type": "Feature", "id":"6", "properties": { "address": "38" }, "geometry": { "type": "Point", "coordinates": [175.2209942 ,-37.8192782833 ] } }
]
};
var tiles = L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
maxZoom: 18,
attribution: '© OpenStreetMap contributors'
});
var map = L.map('map')
.addLayer(tiles);
var markers = L.markerClusterGroup();
var geoJsonLayer = L.geoJson(geoJsonData, {
onEachFeature: function (feature, layer) {
layer.bindPopup(feature.properties.address);
}
});
markers.addLayer(geoJsonLayer);
map.addLayer(markers);
map.fitBounds(markers.getBounds());
</script>
I know it can be done with $.getJSON, but I would prefer using L.geoJson, if possible.

To read JSON data from a file you can use the fetch function (read more).
Here is an example:
fetch('http://example.com/movies.json')
.then(function(response) {
return response.json();
})
.then(function(myJson) {
// Do something with the JSON data
console.table(myJson);
});
In your case:
function doSomething(geoJsonData) {
var tiles = L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
maxZoom: 18,
attribution: '© OpenStreetMap contributors'
});
var map = L.map('map')
.addLayer(tiles);
var markers = L.markerClusterGroup();
var geoJsonLayer = L.geoJson(geoJsonData, {
onEachFeature: function (feature, layer) {
layer.bindPopup(feature.properties.address);
}
});
markers.addLayer(geoJsonLayer);
map.addLayer(markers);
map.fitBounds(markers.getBounds());
}
fetch('http://myserver.com/myfile.json')
.then(function(response) {
return response.json();
})
.then(doSomething)
.catch(function(err) {
// In case of error, display the error message
console.error(err);
});
Notice that I put your code inside a callback function, as the fetch function is asynchronous.

You can store the geoJSON variable in a separate .js file and import it into the main logic .js file. Try pasting your var geoJsonData in a file called geoJsonData.js, then at the bottom of that file add "module.exports = geoJsonData;". Then on your logic file (ie scripts.js), you can import the variable as is by adding "var geoJsonData = require("./geoJsonData.js"); at the top. Then your call to add the points to the map would be
function geoJsonMarkers() {
$.getJSON(geoJsonData, function (data) {
// this adds the GeoJSON layer to the map once the file is loaded
L.geoJson(data).addTo(mymap);
}
}

I know it can be done with $.getJSON, but I would prefer using L.geoJson, if possible.
You seem to not realize that these 2 functions provide different steps of your workflow, as illustrated by the 2 other answers.
You may be misled by other libraries that provide utility functions which perform both steps for you.
jQuery's $.getJSON is to fetch / retrieve data from your server.
Once you have the resulting JS object, you feed it into Leaflet's L.geoJSON factory to have it converted into Leaflet layers.

Leaflet eachLayer function does not iterate through all Layers

Created some markers using an array of GeoJSON data:
$.getJSON("GetLocationsServlet", function(data) {
L.geoJSON(data, {
onEachFeature: onEachFeature
}).addTo(mymap);
});
The GeoJSON data is like this:
[
{ "type": "Feature", "properties": { "name": "Riverway Sport Complex", "amenity": "GYM", "popupContent": "Riverway Sport Complex" }, "geometry": { "type": "Point", "coordinates": [-123.002846, 49.205036] },"id" : "1"} ,
{ "type": "Feature", "properties": { "name": "Imperial#Patterson", "amenity": "GYM", "popupContent": "Imperial#Patterson" }, "geometry": { "type": "Point", "coordinates": [-123.01249, 49.22193] },"id" : "2"}
]
The markers were successfully created and showed on the map. At some point later, I needed to iterate through all Markers, so I used eachLayer function:
var mymap = L.map('mapid').locate({setView: true, maxZoom: 15});
L.tileLayer('https://api.tiles.mapbox.com/v4/{id}/{z}/{x}/{y}.png? '
access_token=..., {
maxZoom: 25,
attribution:
id: 'mapbox.streets',
}).addTo(mymap);
.......
$.getJSON( L.geoJSON()... )
.......
mymap.eachLayer(function(layer) {
alert (layer.options.id);
// Above alert successfully print out the tileLayer ID
if (layer instanceof L.Marker) {
alert("Marker [" + layer.options.title + "]");
}
});
However, it only looped through the main map tileLayer and stopped.
Am I using the eachLayer method correctly? Marker is also a subclass of Layer?
Thanks,

Openlayers 3 z-ordering of features

I have a vector layer, which contains polygons and points loaded from GEOJSON source. It looks to me, points are always positioned above polygons regardless of their order in source GEOJSON file. See an example definition below. Is there a way, how to position points below polygons on the same layer?
The example:
Points are styled as white and red circle. Polygon is gray.
My GEOJSON looks like this (I even tried to reverse features order in the file):
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"radius": "1000"
},
"geometry": {
"type": "Point",
"coordinates": [
12.4,
50.08333
]
}
},
{
"type": "Feature",
"properties": {
"radius": "800"
},
"geometry": {
"type": "Point",
"coordinates": [
12.4,
50.08333
]
}
},
{
"type": "Feature",
"geometry": {
"type": "Polygon",
"coordinates": [[
[
12.4,
50.08333
],
...........

Use zIndex in the style objects.

Parent polygon in Leaflet js

I would like to wrap multiple polygons in a parent polygon. Example below:
Is this possible in Leaflet js? Assume I have an array of L.polygon objects.
Thank you

Short answer: no.
If you want to create an envelope for your polygones, then it is an algorithm problem that goes beyond the scope of leafletjs.
You can look at the answers of this question to start solving your problem.
EDIT: here is an example using Turfjs library (thanks to #IvanSanchez for the heads up and to #HudsonPH for the polygons).
// draw envelope
var points = {
"type": "FeatureCollection",
"features":
[
// collect the points of your polygons
turf.point([-104.05, 48.99]),
// ...
]
};
var hull = turf.convex(points);
L.geoJson(hull).addTo(map);

You can have a group, but you need define all the coordinates
more info: http://leafletjs.com/examples/geojson.html
var states = [{
"type": "Feature",
"properties": {"party": "Republican"},
"geometry": {
"type": "Polygon",
"coordinates": [[
[-104.05, 48.99],
[-97.22, 48.98],
[-96.58, 45.94],
[-104.03, 45.94],
[-104.05, 48.99]
]]
}
}, {
"type": "Feature",
"properties": {"party": "Democrat"},
"geometry": {
"type": "Polygon",
"coordinates": [[
[-109.05, 41.00],
[-102.06, 40.99],
[-102.03, 36.99],
[-109.04, 36.99],
[-109.05, 41.00]
]]
}
}];
L.geoJson(states, {
style: function(feature) {
switch (feature.properties.party) {
case 'Republican': return {color: "#ff0000"};
case 'Democrat': return {color: "#0000ff"};
}
}
}).addTo(map);