Mapbox GL JS: Style is not done loading - mapbox

Question

I have a map wher we can classically switch from one style to another, streets to satellite for example.
I want to be informed that the style is loaded to then add a layer.
According to the doc, I tried to wait that the style being loaded to add a layer based on a GEOJson dataset.
That works perfectly when the page is loaded which fires map.on('load') but I get an error when I just change the style, so when adding layer from map.on('styledataloading'), and I even get memory problems in Firefox.
My code is:
mapboxgl.accessToken = 'pk.token';
var map = new mapboxgl.Map({
container: 'map',
style: 'mapbox://styles/mapbox/streets-v10',
center: [5,45.5],
zoom: 7
});
map.on('load', function () {
loadRegionMask();
});
map.on('styledataloading', function (styledata) {
if (map.isStyleLoaded()) {
loadRegionMask();
}
});
$('#typeMap').on('click', function switchLayer(layer) {
var layerId = layer.target.control.id;
switch (layerId) {
case 'streets':
map.setStyle('mapbox://styles/mapbox/' + layerId + '-v10');
break;
case 'satellite':
map.setStyle('mapbox://styles/mapbox/satellite-streets-v9');
break;
}
});
function loadJSON(callback) {
var xobj = new XMLHttpRequest();
xobj.overrideMimeType("application/json");
xobj.open('GET', 'regions.json', true);
xobj.onreadystatechange = function () {
if (xobj.readyState == 4 && xobj.status == "200") {
callback(xobj.responseText);
}
};
xobj.send(null);
}
function loadRegionMask() {
loadJSON(function(response) {
var geoPoints_JSON = JSON.parse(response);
map.addSource("region-boundaries", {
'type': 'geojson',
'data': geoPoints_JSON,
});
map.addLayer({
'id': 'region-fill',
'type': 'fill',
'source': "region-boundaries",
'layout': {},
'paint': {
'fill-color': '#C4633F',
'fill-opacity': 0.5
},
"filter": ["==", "$type", "Polygon"]
});
});
}
And the error is:
Uncaught Error: Style is not done loading
at t._checkLoaded (mapbox-gl.js:308)
at t.addSource (mapbox-gl.js:308)
at e.addSource (mapbox-gl.js:390)
at map.js:92 (map.addSource("region-boundaries",...)
at XMLHttpRequest.xobj.onreadystatechange (map.js:63)
Why do I get this error whereas I call loadRegionMask() after testing that the style is loaded?

Answer 1

1. Listen styledata event to solve your problem
You may need to listen styledata event in your project, since this is the only standard event mentioned in mapbox-gl-js documents, see https://docs.mapbox.com/mapbox-gl-js/api/#map.event:styledata.
You can use it in this way:
map.on('styledata', function() {
addLayer();
});
2. Reasons why you shouldn't use other methods mentioned above
setTimeout may work but is not a recommend way to solve the problem, and you would got unexpected result if your render work is heavy;
style.load is a private event in mapbox, as discussed in issue https://github.com/mapbox/mapbox-gl-js/issues/7579, so we shouldn't listen to it apparently;
.isStyleLoaded() works but can't be called all the time until style is full loaded, you need a listener rather than a judgement method;

Answer 2

Ok, this mapbox issue sucks, but I have a solution
myMap.on('styledata', () => {
const waiting = () => {
if (!myMap.isStyleLoaded()) {
setTimeout(waiting, 200);
} else {
loadMyLayers();
}
};
waiting();
});
I mix both solutions.

Answer 3

I was facing a similar issue and ended up with this solution:
I created a small function that would check if the style was done loading:
// Check if the Mapbox-GL style is loaded.
function checkIfMapboxStyleIsLoaded() {
if (map.isStyleLoaded()) {
return true; // When it is safe to manipulate layers
} else {
return false; // When it is not safe to manipulate layers
}
}
Then whenever I swap or otherwise modify layers in the app I use the function like this:
function swapLayer() {
var check = checkIfMapboxStyleIsLoaded();
if (!check) {
// It's not safe to manipulate layers yet, so wait 200ms and then check again
setTimeout(function() {
swapLayer();
}, 200);
return;
}
// Whew, now it's safe to manipulate layers!
the rest of the swapLayer logic goes here...
}

Answer 4

Use the style.load event. It will trigger once each time a new style loads.
map.on('style.load', function() {
addLayer();
});

Answer 5

My working example:
when I change style
map.setStyle()
I get error Uncaught Error: Style is not done loading
This solved my problem
Do not use map.on("load", loadTiles);
instead use
map.on('styledata', function() {
addLayer();
});
when you change style, map.setStyle(), you must wait for setStyle() finished, then to add other layers.
so far map.setStyle('xxx', callback) Does not allowed. To wait until callback, work around is use map.on("styledata"
map.on("load" not work, if you change map.setStyle(). you will get error: Uncaught Error: Style is not done loading

Answer 6

The current style event structure is broken (at least as of Mapbox GL v1.3.0). If you check map.isStyleLoaded() in the styledata event handler, it always resolves to false:
map.on('styledata', function (e) {
if (map.isStyleLoaded()){
// This never happens...
}
}
My solution is to create a new event called "style_finally_loaded" that gets fired only once, and only when the style has actually loaded:
var checking_style_status = false;
map.on('styledata', function (e) {
if (checking_style_status){
// If already checking style status, bail out
// (important because styledata event may fire multiple times)
return;
} else {
checking_style_status = true;
check_style_status();
}
});
function check_style_status() {
if (map.isStyleLoaded()) {
checking_style_status = false;
map._container.trigger('map_style_finally_loaded');
} else {
// If not yet loaded, repeat check after delay:
setTimeout(function() {check_style_status();}, 200);
return;
}
}

Answer 7

I had the same problem, when adding real estate markers to the map. For the first time addding the markers I wait till the map turns idle. After it was added once I save this in realEstateWasInitialLoaded and just add it afterwards without any waiting. But make sure to reset realEstateWasInitialLoaded to false when changing the base map or something similar.
checkIfRealEstateLayerCanBeAddedAndAdd() {
/* The map must exist and real estates must be ready */
if (this.map && this.realEstates) {
this.map.once('idle', () => {
if (!this.realEstateWasInitialLoaded) {
this.addRealEstatesLayer();
this.realEstateWasInitialLoaded = true
}
})
if(this.realEstateWasInitialLoaded) {
this.addRealEstatesLayer();
}
}
},

Answer 8

I ended up with :
map.once("idle", ()=>{ ... some function here});
In case you have a bunch of stuff you want to do , i would do something like this =>
add them to an array which looks like [{func: function, param: params}], then you have another function which does this:
executeActions(actions) {
actions.forEach((action) => {
action.func(action.params);
});
And at the end you have
this.map.once("idle", () => {
this.executeActions(actionsArray);
});

Answer 9

I have created simple solution. Give 1 second for mapbox to load the style after you set the style and you can draw the layer
map.setStyle(styleUrl);
setTimeout(function(){
reDrawMapSourceAndLayer(); /// your function layer
}, 1000);
when you use map.on('styledataloading') it will trigger couple of time when you changes the style
map.on('styledataloading', () => {
const waiting = () => {
if (!myMap.isStyleLoaded()) {
setTimeout(waiting, 200);
} else {
loadMyLayers();
}
};
waiting();
});