Configuration

Minimal config

A version number and one basemap are enough to start. Other settings have defaults that you can override as needed.

Defaults in use: this config leaves the view, controls and theme unspecified. The viewer adds zoom, compass, fullscreen, location, globe view, scale bar, attribution, coordinates and print, with a colour scheme that follows the system.

The whole thing

The config above is embedded directly in the page:

minimal.html

<script type="module" src="/map0.js"></script>

<map0-viewer style="height:520px">
  <script type="application/json">
    {
      "version": 1,
      "basemaps": [
        {
          "type": "style",
          "url": "https://mapsneu.wien.gv.at/basemapv/bmapv/3857/resources/styles/root.json"
        }
      ]
    }
  </script>
</map0-viewer>

Three ways to hand over a config, in this order of precedence:

A config property set from JavaScript (for SPAs and wrappers)
A config-src attribute pointing at a JSON file
A <script type="application/json"> child inside the element, as shown above

When the config is wrong

The viewer validates the config before rendering. Errors appear in place with the JSON path of the affected setting:

error panel

$.basemaps          at least one basemap is required, e.g. { "type": "style", "url": "…" }
$.layers[2].url     a "wms" layer needs a "url"
$.layers[2].layers  a "wms" layer needs "layers" (WMS LAYERS parameter)