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Set collision behavior for a marker

Page Summary

This example demonstrates how to manage marker collisions on a map using the AdvancedMarkerElement and CollisionBehavior properties.
Users can interactively select different collision behaviors to control how markers overlap or hide each other.
The sample code utilizes the Google Maps JavaScript API with TypeScript and JavaScript examples provided.
The code dynamically creates and positions multiple markers on the map, showcasing the impact of the selected collision behavior.
A dropdown menu allows users to choose between various collision behaviors, dynamically updating the marker display.

This example shows setting collision behavior for a marker.

Read the documentation.

TypeScript

const mapElement = document.querySelector('gmp-map')!;

declare namespace mdc {
    namespace select {
        class MDCSelect {
            constructor(el: Element | null);
            listen(evtType: string, handler: (event: Event) => void): void;
            value: string;
        }
    }
}

// Initialize and add the map
async function init(): Promise<void> {
    // Request needed libraries.
    const [{ AdvancedMarkerElement }] = await Promise.all([
        google.maps.importLibrary('marker'),
        google.maps.importLibrary('maps'),
    ]);

    const markers: google.maps.marker.AdvancedMarkerElement[] = [];

    const collisionBehavior: google.maps.CollisionBehaviorString = 'REQUIRED';

    const select = new mdc.select.MDCSelect(
        document.querySelector('.mdc-select')
    );

    select.listen('MDCSelect:change', () => {
        markers.forEach((marker) => {
            marker.collisionBehavior =
                select.value as google.maps.CollisionBehavior;
        });
    });

    select.value = collisionBehavior;

    // Create some markers on the map
    const locations = [
        [-122.3402, 47.6093],
        [-122.3402, 47.6094],
        [-122.3403, 47.6094],
        [-122.3384, 47.6098],
        [-122.3389, 47.6095],
        [-122.3396, 47.6095],
        [-122.3379, 47.6097],
        [-122.3378, 47.6097],
        [-122.3396, 47.6091],
        [-122.3383, 47.6089],
        [-122.3379, 47.6093],
        [-122.3381, 47.6095],
        [-122.3378, 47.6095],
    ];

    locations.forEach(([lng, lat]: number[]) => {
        const advancedMarker = new AdvancedMarkerElement({
            position: { lat, lng },
            collisionBehavior,
        });
        mapElement.appendChild(advancedMarker);
        markers.push(advancedMarker);
    });
}

void init();index.ts

JavaScript

const mapElement = document.querySelector('gmp-map');

// Initialize and add the map
async function init() {
    // Request needed libraries.
    const [{ AdvancedMarkerElement }] = await Promise.all([
        google.maps.importLibrary('marker'),
        google.maps.importLibrary('maps'),
    ]);

    const markers = [];

    const collisionBehavior = 'REQUIRED';

    const select = new mdc.select.MDCSelect(
        document.querySelector('.mdc-select')
    );

    select.listen('MDCSelect:change', () => {
        markers.forEach((marker) => {
            marker.collisionBehavior = select.value;
        });
    });

    select.value = collisionBehavior;

    // Create some markers on the map
    const locations = [
        [-122.3402, 47.6093],
        [-122.3402, 47.6094],
        [-122.3403, 47.6094],
        [-122.3384, 47.6098],
        [-122.3389, 47.6095],
        [-122.3396, 47.6095],
        [-122.3379, 47.6097],
        [-122.3378, 47.6097],
        [-122.3396, 47.6091],
        [-122.3383, 47.6089],
        [-122.3379, 47.6093],
        [-122.3381, 47.6095],
        [-122.3378, 47.6095],
    ];

    locations.forEach(([lng, lat]) => {
        const advancedMarker = new AdvancedMarkerElement({
            position: { lat, lng },
            collisionBehavior,
        });
        mapElement.appendChild(advancedMarker);
        markers.push(advancedMarker);
    });
}

void init();index.js

CSS

:root {
    --mdc-theme-primary: #1a73e8;
    --mdc-theme-secondary: #rgb(225, 245, 254);
    --mdc-theme-on-primary: #fff;
    --mdc-theme-on-secondary: rgb(1, 87, 155);
}

.mdc-text-field--focused:not(.mdc-text-field--disabled) .mdc-floating-label {
    color: var(--mdc-theme-primary);
}

.mdc-select--focused .mdc-select__dropdown-icon {
    background: url(data:image/svg+xml,%3Csvg%20width%3D%2210px%22%20height%3D%225px%22%20viewBox%3D%227%2010%2010%205%22%20version%3D%221.1%22%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20xmlns%3Axlink%3D%22http%3A%2F%2Fwww.w3.org%2F1999%2Fxlink%22%3E%0A%20%20%20%20%3Cpolygon%20id%3D%22Shape%22%20stroke%3D%22none%22%20fill%3D%22%23000%22%20fill-rule%3D%22evenodd%22%20opacity%3D%220.54%22%20points%3D%227%2010%2012%2015%2017%2010%22%3E%3C%2Fpolygon%3E%0A%3C%2Fsvg%3E)
        no-repeat center;
}

.mdc-select:not(.mdc-select--disabled).mdc-select--focused .mdc-floating-label {
    color: var(--mdc-theme-primary);
}

/* Optional: Makes the sample page fill the window. */
html,
body {
    height: 100%;
    margin: 0;
    padding: 0;
}

#container {
    height: 100%;
    display: flex;
}

#sidebar {
    flex-basis: 15rem;
    flex-grow: 1;
    padding: 1rem;
    max-width: 33rem;
    height: 100%;
    box-sizing: border-box;
    overflow: auto;
}

gmp-map {
    flex-basis: 0;
    flex-grow: 4;
    height: 100%;
}

.mdc-select,
.mdc-select__anchor,
.mdc-select__menu {
    width: 100%;
}
style.css

HTML

<html>
    <head>
        <title>Advanced Marker Collision Management</title>

        <link
            href="https://unpkg.com/material-components-web@6.0.0/dist/material-components-web.css"
            rel="stylesheet" />
        <script src="https://unpkg.com/material-components-web@6.0.0/dist/material-components-web.min.js"></script>
        <link
            rel="stylesheet"
            href="https://fonts.googleapis.com/icon?family=Material+Icons" />

        <link rel="stylesheet" type="text/css" href="./style.css" />
        <script type="module" src="./index.js"></script>
        <script>
            // prettier-ignore
            (g=>{var h,a,k,p="The Google Maps JavaScript API",c="google",l="importLibrary",q="__ib__",m=document,b=window;b=b[c]||(b[c]={});var d=b.maps||(b.maps={}),r=new Set,e=new URLSearchParams,u=()=>h||(h=new Promise(async(f,n)=>{await (a=m.createElement("script"));e.set("libraries",[...r]+"");for(k in g)e.set(k.replace(/[A-Z]/g,t=>"_"+t[0].toLowerCase()),g[k]);e.set("callback",c+".maps."+q);a.src=`https://maps.${c}apis.com/maps/api/js?`+e;d[q]=f;a.onerror=()=>h=n(Error(p+" could not load."));a.nonce=m.querySelector("script[nonce]")?.nonce||"";m.head.append(a)}));d[l]?console.warn(p+" only loads once. Ignoring:",g):d[l]=(f,...n)=>r.add(f)&&u().then(()=>d[l](f,...n))})({
                key: "GOOGLE_MAPS_API_KEY"
            });
        </script>
    </head>
    <body>
        <div id="container">
            <gmp-map
                center="47.609414458375674,-122.33897030353548"
                zoom="17"
                map-id="6ff586e93e18149f"></gmp-map>
            <div id="sidebar">
                <div class="mdc-select mdc-select--outlined">
                    <div
                        class="mdc-select__anchor"
                        aria-labelledby="outlined-select-label">
                        <input
                            type="text"
                            disabled
                            readonly
                            id="demo-selected-text"
                            class="mdc-select__selected-text" />
                        <i class="mdc-select__dropdown-icon"></i>
                        <span class="mdc-notched-outline">
                            <span class="mdc-notched-outline__leading"></span>
                            <span class="mdc-notched-outline__notch">
                                <span
                                    id="outlined-select-label"
                                    class="mdc-floating-label mdc-theme--primary"
                                    >Pick a Collision Behavior</span
                                >
                            </span>
                            <span class="mdc-notched-outline__trailing"></span>
                        </span>
                    </div>
                    <div class="mdc-select__menu mdc-menu mdc-menu-surface">
                        <ul class="mdc-list">
                            <li class="mdc-list-item" data-value="REQUIRED">
                                Required
                            </li>
                            <li
                                class="mdc-list-item"
                                data-value="REQUIRED_AND_HIDES_OPTIONAL">
                                Required and hides optional
                            </li>
                            <li
                                class="mdc-list-item"
                                data-value="OPTIONAL_AND_HIDES_LOWER_PRIORITY">
                                Optional and hides lower priority
                            </li>
                        </ul>
                    </div>
                </div>
            </div>
        </div>
    </body>
</html>index.html

Clone Sample

Git and Node.js are required to run this sample locally. Follow these instructions to install Node.js and NPM. You will also need a Google Maps API key.

The following commands clone the repository, install dependencies, and copy the environment file.

  git clone https://github.com/googlemaps-samples/js-api-samples.git
  cd js-api-samples
  npm i
  cp .env.template .env

Once you copy the environment file, make sure to open the .env file and replace <Insert your own development API key here> with your actual API key before starting the sample.

  cd samples/advanced-markers-collision
  npm start