When loading a geoJSON file into a Google Map as a data layer, how does one access the properties of the data layer itself?

I know how to access the individual properties, like posts_here in the below example. What I'm looking to get is the properties for the layer itself- in this example, maxPosts.

$.getJSON(".json" + location.search, function (data) {
        grid = map_canvas.data.addGeoJson(data);
        map_canvas.data.setStyle(function(feature) {
        return /** @type {google.maps.Data.StyleOptions} */({
            strokeWeight: Math.log(feature.getProperty('posts_here')),
        });
    })
});

Example of the grid.json I'm loading:

{
    "type": "FeatureCollection",
    "features": [
        {
            "type": "Feature",
            "geometry": {
                "type": "Polygon",
                "coordinates": [
                    [
                        [-58,-35],
                        [-58,-34],
                        [-57,-34],
                        [-57,-35],
                        [-58,-35]
                    ]
                ]
            },
            "properties": {
                "posts_here": "177"
            }
        }
    ],
    "properties": {
        "maxPosts": "177"
    }
}

When loading a geoJSON file into a Google Map as a data layer, how does one access the properties of the data layer itself?

I know how to access the individual properties, like posts_here in the below example. What I'm looking to get is the properties for the layer itself- in this example, maxPosts.

$.getJSON("http://example./posts/grid.json" + location.search, function (data) {
        grid = map_canvas.data.addGeoJson(data);
        map_canvas.data.setStyle(function(feature) {
        return /** @type {google.maps.Data.StyleOptions} */({
            strokeWeight: Math.log(feature.getProperty('posts_here')),
        });
    })
});

Example of the grid.json I'm loading:

{
    "type": "FeatureCollection",
    "features": [
        {
            "type": "Feature",
            "geometry": {
                "type": "Polygon",
                "coordinates": [
                    [
                        [-58,-35],
                        [-58,-34],
                        [-57,-34],
                        [-57,-35],
                        [-58,-35]
                    ]
                ]
            },
            "properties": {
                "posts_here": "177"
            }
        }
    ],
    "properties": {
        "maxPosts": "177"
    }
}

• javascript
• jquery
• google-maps
• google-maps-api-3

2 Answers 2

The API does only parse the features-array of a FeatureCollection, when you want to access additional properties you must implement it on your own.

Based on the given code it isn't plicated, because the geoJson is accessible as object via data inside the $.getJSON-callback, you may simply access the property via

data.properties.maxPosts

I believe you should be able to use getFeatureById(id:number|string) to access information you've added from your geoJSON.