Area API

Per-option reference for the area field. For setup and worked examples, see the Area guide.

Options are passed to the field declaration in an Avo resource's fields method:

field :city_center_area, as: :area, geometry: :polygon

For labels, visibility, placeholders, and other shared settings, see Common field options.

Geometry selection

-> geometry

Sets the GeoJSON geometry type for the stored coordinates. Avo converts the value to a string and classifies it, so :multi_polygon becomes "MultiPolygon".

field :city_center_area, as: :area, geometry: :multi_polygon

Value	Behavior
:polygon	Produces a Polygon; coordinates are an array of linear rings, with the exterior ring first and any holes after it.
:multi_polygon	Produces a MultiPolygon; coordinates are an array of polygon coordinate arrays.

• Type: Symbol or String.
• Default: :polygon; blank values also fall back to this default.
• Values: :polygon and :multi_polygon, or their string equivalents.
• Validation: Avo does not validate the geometry type or coordinate structure.

Map rendering

-> mapkick_options

Options forwarded as keyword arguments to Mapkick's area_map helper. Avo merges these over {style: Avo::MapStyles.light}, so a supplied style overrides the resolved light style.

field :city_center_area, as: :area, mapkick_options: {controls: true}

• Type: Hash with symbol keys.
• Default: {} before merging with Avo's default style.
• Values: Options supported by Mapkick.
• Validation: No Avo validation of Mapkick options; nonblank values must support Hash merging.

The resolved styles come from config.map_view. With no global override, Avo uses OpenFreeMap's "https://tiles.openfreemap.org/styles/positron" in light mode and "https://tiles.openfreemap.org/styles/dark" in dark mode. When MAPBOX_ACCESS_TOKEN is present, those defaults become "mapbox://styles/mapbox/light-v11" and "mapbox://styles/mapbox/dark-v11".

INFO

A nonblank style opts this map out of automatic light/dark style switching. Without a custom style, Avo follows the configured color scheme using the resolved style pair.

-> datapoint_options

Options merged into the area's data point after Avo constructs its geometry. These can supply a label, tooltip, or color.

field :city_center_area, as: :area, datapoint_options: {label: "Paris City Center", color: "#009099"}

• Type: Hash with symbol keys.
• Default: {}.
• Values: Data point options supported by Mapkick area maps, including label, tooltip, and color.
• Validation: No Avo validation of data point options; nonblank values must support Hash merging.

WARNING

The merge is shallow. A geometry key in datapoint_options replaces the generated geometry entirely.