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.
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Basic flow
This example show how to render LineString/Multiline features with color, width, dash, and outline.
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 reference to understand how to create and manage point layers.
Review MTPolylineLayerOptions to explore all available configuration options.
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