---
title: "Polygon Helper - Kotlin SDK | Mobile sdk | Mobile sdk android | Android"
description: "Add polygon features to maps using Kotlin layer helpers."
---

# Polygon Helper - Kotlin SDK

This example show how to render Polygon/Multipolygon features with styles options like fill, optional pattern, and outline.

The vector layer helpers take your data and styling options and create the right source + layers on the current map style with minimal code. Helpers normalize sensible defaults like zoom range, outlines, etc. so you can get results quickly.

![Polygon Helper - Kotlin SDK](https://docs.maptiler.com/mobile-sdk/android/assets/img/thumbnails/polygon-helper.png)

## Basic flow

This example show how to render Polygon/Multipolygon features with fill, optional pattern, and outline.

```kotlin
import com.maptiler.maptilersdk.map.MTMapView
import com.maptiler.maptilersdk.map.MTMapOptions
import com.maptiler.maptilersdk.map.MTMapViewController
import com.maptiler.maptilersdk.map.style.MTMapReferenceStyle
import com.maptiler.maptilersdk.helpers.MTPolygonLayerOptions
import com.maptiler.maptilersdk.helpers.MTPolygonLayerHelper

// After your MTMapView is on screen (Compose example)
val controller = MTMapViewController(context)
MTMapView(
    referenceStyle = MTMapReferenceStyle.DATAVIZ,
    options = MTMapOptions(),
    controller = controller,
)

// 1) Get the style once available
controller.style?.let { style ->
    val helper = style.polygonHelper()
    val polygonOptions = MTPolygonLayerOptions(
        data = "...GeoJSON polygon(s)...", // URL or inline string
        fillColor = "#1e90ff",
        fillOpacity = 0.5,
        outline = true,
        outlineColor = "white",
        outlineWidth = 1.2,
        outlineOpacity = 0.9,
    )
    helper.addPolygon(polygonOptions)
}
```

## Learn more

Check the [MTPolygonLayerHelper](https://docs.maptiler.com/mobile-sdk/android/api/-map-tiler-s-d-k/com.maptiler.maptilersdk.helpers/-m-t-polygon-layer-helper/) reference to understand how to create and manage point layers.

Review [MTPolygonLayerOptions](https://docs.maptiler.com/mobile-sdk/android/api/-map-tiler-s-d-k/com.maptiler.maptilersdk.helpers/-m-t-polygon-layer-options/) to explore all available configuration options.

## Related examples

### [Point Helper](https://docs.maptiler.com/mobile-sdk/android/examples/point-helper/)

Examples

Add point features and clustering using Kotlin layer helpers.

### [Polyline Helper](https://docs.maptiler.com/mobile-sdk/android/examples/polyline-helper/)

Examples

Add polyline features to maps using Kotlin layer helpers.

### [Heatmap Helper](https://docs.maptiler.com/mobile-sdk/android/examples/heatmap-helper/)

Examples

Aggregate point features into heatmaps using Kotlin SDK helpers.

### [Point Helper Clusters](https://docs.maptiler.com/mobile-sdk/android/examples/point-helper-cluster/)

Examples

Generate cluster maps using the point layer helper defaults.