---
title: "itemForPolygon(overlay, geoJSON)"
framework: mapkitjs
role: symbol
role_heading: Interface Method
path: mapkitjs/geojsondelegate/itemforpolygon
---

# itemForPolygon(overlay, geoJSON)

Overrides a polygon.

## Declaration

```data
itemForPolygon?(
    overlay: PolygonOverlay,
    geoJSON: GeoJSONTypes.Polygon,
): PolygonOverlay | null;
```

## Parameters

- `overlay`: You can customize the provided overlay before returning it, or you can completely replace the overlay.
- `geoJSON`: The original GeoJSON object for the polygon.

## Return Value

Return Value A map item or an array of map items.

## Discussion

Discussion MapKit JS calls this method for each individual polygon geometry object. The framework breaks MultiPolygon geometry types into individual polygon types.

## See Also

### Overriding items

- [itemForFeature(item, geoJSON)](mapkitjs/geojsondelegate/itemforfeature.md)
- [itemForFeatureCollection(itemCollection, geoJSON)](mapkitjs/geojsondelegate/itemforfeaturecollection.md)
- [itemForLineString(overlay, geoJSON)](mapkitjs/geojsondelegate/itemforlinestring.md)
- [itemForMultiLineString(itemCollection, geoJSON)](mapkitjs/geojsondelegate/itemformultilinestring.md)
- [itemForPoint(coordinate, geoJSON)](mapkitjs/geojsondelegate/itemforpoint.md)
- [itemForMultiPoint(itemCollection, geoJSON)](mapkitjs/geojsondelegate/itemformultipoint.md)
- [itemForMultiPolygon(itemCollection, geoJSON)](mapkitjs/geojsondelegate/itemformultipolygon.md)
- [styleForOverlay(overlay, geoJSON)](mapkitjs/geojsondelegate/styleforoverlay.md)