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

# Polyline Helper - Kotlin SDK

This example show how to render LineString/Multiline features with styles options like color, width, dash, 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.

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

## Basic flow

This example show how to render LineString/Multiline features with color, width, dash, 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.MTPolylineLayerOptions
import com.maptiler.maptilersdk.helpers.MTPolylineLayerHelper

// 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.polylineHelper()
    val lineGeoJSON = """
        {"type":"FeatureCollection","features":[
          {"type":"Feature","geometry":{"type":"LineString","coordinates":[[-122.48,37.80],[-122.40,37.78],[-122.35,37.76]]}},
          {"type":"Feature","geometry":{"type":"LineString","coordinates":[[-122.50,37.74],[-122.43,37.72],[-122.38,37.70]]}}
        ]}
    """.trimIndent()
    val options = MTPolylineLayerOptions(
        data = lineGeoJSON,
        lineColor = "#ff7f50",
        lineWidth = 3.0,
        lineOpacity = 0.95,
        lineDashPattern = "__ __ __ __", // or pass MTDashArrayOption.Numbers(...)
        outline = true,
        outlineColor = "#202020",
        outlineWidth = 1.0,
        outlineOpacity = 0.8,
    )
    helper.addPolyline(options)
}
```

## Learn more

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

Review [MTPolylineLayerOptions](https://docs.maptiler.com/mobile-sdk/android/api/-map-tiler-s-d-k/com.maptiler.maptilersdk.helpers/-m-t-polyline-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.

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

Examples

Add polygon 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.