Adding KML layer with an image layer - Not Loading - google-maps

Question

I am trying to add custom overlay & Kml layer. The custom layer is working, but the KML layer is not showing at all. What would cause this?
var overlay;
USGSOverlay.prototype = new google.maps.OverlayView();
// Initialize the map and the custom overlay.
function initMap() {
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 16,
center: {lat: 31.1917, lng: 27.56553},
mapTypeId: 'satellite'
});
var bounds = new google.maps.LatLngBounds(
new google.maps.LatLng(31.18954, 27.56144),
new google.maps.LatLng(31.19277, 27.56806));
var srcImage = 'https://travcop.zohosites.com/selc02.png';
overlay = new USGSOverlay(bounds, srcImage, map);
}
/** #constructor */
function USGSOverlay(bounds, image, map) {
// Initialize all properties.
this.bounds_ = bounds;
this.image_ = image;
this.map_ = map;
// Define a property to hold the image's div. We'll
// actually create this div upon receipt of the onAdd()
// method so we'll leave it null for now.
this.div_ = null;
// Explicitly call setMap on this overlay.
this.setMap(map);
}
/**
* onAdd is called when the map's panes are ready and the overlay has been
* added to the map.
*/
USGSOverlay.prototype.onAdd = function() {
var div = document.createElement('div');
div.style.borderStyle = 'none';
div.style.borderWidth = '0px';
div.style.position = 'absolute';
// Create the img element and attach it to the div.
var img = document.createElement('img');
img.src = this.image_;
img.style.width = '100%';
img.style.height = '100%';
img.style.position = 'absolute';
div.appendChild(img);
this.div_ = div;
// Add the element to the "overlayLayer" pane.
var panes = this.getPanes();
panes.overlayLayer.appendChild(div);
};
USGSOverlay.prototype.draw = function() {
var sw = overlayProjection.fromLatLngToDivPixel(this.bounds_.getSouthWest());
var ne = overlayProjection.fromLatLngToDivPixel(this.bounds_.getNorthEast());
// Resize the image's div to fit the indicated dimensions.
var div = this.div_;
div.style.left = sw.x + 'px';
div.style.top = ne.y + 'px';
div.style.width = (ne.x - sw.x) + 'px';
div.style.height = (sw.y - ne.y) + 'px';
};
var kmlLayer = new google.maps.KmlLayer({
url: 'https://travcop.zohosites.com/sel.kml',
suppressInfoWindows: true,
map: map
});
function showInContentWindow(text) {
var sidediv = document.getElementById('content-window');
sidediv.innerHTML = text;
}
// The onRemove() method will be called automatically from the API if
// we ever set the overlay's map property to 'null'.
USGSOverlay.prototype.onRemove = function() {
this.div_.parentNode.removeChild(this.div_);
this.div_ = null;
};
google.maps.event.addDomListener(window, 'load', initMap);
I am not sure why the KML layer is not loading. Could be the two layers loading in the same time?
Trying to create a real estate portal where data is marked in KML and the map is for a future project that is not yet displayed on Google Maps

Answer 1

I get a javascript error with the posted code: Uncaught ReferenceError: map is not defined.
The map variable is local to your initMap function, you need to instantiate the KmlLayer inside your initMap method.
function initMap() {
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 16,
center: {lat: 31.1917, lng: 27.56553},
mapTypeId: 'satellite'
});
var bounds = new google.maps.LatLngBounds(
new google.maps.LatLng(31.18954, 27.56144),
new google.maps.LatLng(31.19277, 27.56806));
var srcImage = 'https://travcop.zohosites.com/selc02.png';
overlay = new USGSOverlay(bounds, srcImage, map);
var kmlLayer = new google.maps.KmlLayer({
url: 'https://travcop.zohosites.com/sel.kml',
suppressInfoWindows: true,
preserveViewport: true,
map: map
});
}
Once I fix that, there is another error: Uncaught ReferenceError: overlayProjection is not defined, because overlayProjection isn't defined. Taking the definition from Google's example fixes that.
proof of concept fiddle
code snippet:
var overlay;
USGSOverlay.prototype = new google.maps.OverlayView();
// Initialize the map and the custom overlay.
function initMap() {
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 16,
center: {
lat: 31.1917,
lng: 27.56553
},
mapTypeId: 'satellite'
});
var bounds = new google.maps.LatLngBounds(
new google.maps.LatLng(31.18954, 27.56144),
new google.maps.LatLng(31.19277, 27.56806));
var srcImage = 'https://travcop.zohosites.com/selc02.png';
overlay = new USGSOverlay(bounds, srcImage, map);
var kmlLayer = new google.maps.KmlLayer({
url: 'https://travcop.zohosites.com/sel.kml',
suppressInfoWindows: true,
preserveViewport: true,
map: map
});
google.maps.event.addListener(kmlLayer, 'status_changed', function() {
console.log(kmlLayer.getStatus());
})
map.fitBounds(bounds);
}
/** #constructor */
function USGSOverlay(bounds, image, map) {
// Initialize all properties.
this.bounds_ = bounds;
this.image_ = image;
this.map_ = map;
// Define a property to hold the image's div. We'll
// actually create this div upon receipt of the onAdd()
// method so we'll leave it null for now.
this.div_ = null;
// Explicitly call setMap on this overlay.
this.setMap(map);
}
/**
* onAdd is called when the map's panes are ready and the overlay has been
* added to the map.
*/
USGSOverlay.prototype.onAdd = function() {
var div = document.createElement('div');
div.style.borderStyle = 'none';
div.style.borderWidth = '0px';
div.style.position = 'absolute';
// Create the img element and attach it to the div.
var img = document.createElement('img');
img.src = this.image_;
img.style.width = '100%';
img.style.height = '100%';
img.style.position = 'absolute';
div.appendChild(img);
this.div_ = div;
// Add the element to the "overlayLayer" pane.
var panes = this.getPanes();
panes.overlayLayer.appendChild(div);
};
USGSOverlay.prototype.draw = function() {
var overlayProjection = this.getProjection();
var sw = overlayProjection.fromLatLngToDivPixel(this.bounds_.getSouthWest());
var ne = overlayProjection.fromLatLngToDivPixel(this.bounds_.getNorthEast());
// Resize the image's div to fit the indicated dimensions.
var div = this.div_;
div.style.left = sw.x + 'px';
div.style.top = ne.y + 'px';
div.style.width = (ne.x - sw.x) + 'px';
div.style.height = (sw.y - ne.y) + 'px';
};
function showInContentWindow(text) {
var sidediv = document.getElementById('content-window');
sidediv.innerHTML = text;
}
// The onRemove() method will be called automatically from the API if
// we ever set the overlay's map property to 'null'.
USGSOverlay.prototype.onRemove = function() {
this.div_.parentNode.removeChild(this.div_);
this.div_ = null;
};
google.maps.event.addDomListener(window, 'load', initMap);
html,
body,
#map {
height: 100%;
width: 100%;
margin: 0px;
padding: 0px;
}
<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></script>
<div id="map"></div>