Markers

Markers are a Jetpack Compose convenience feature that creates customizable pin-style markers displayed above the map. They are ideal for quickly symbolizing a point on the map without needing custom image assets.

Benefits:

• No image assets required - uses built-in default marker design
• Simple API with essential customization options (color, stroke, inner color, text)
• Quick to implement for common use cases

Limitations:

• Jetpack Compose only (not available with traditional Android Views)
• Limited styling compared to annotations or view annotations
• Less efficient for large datasets (100+ markers)

Experimental Feature

Markers are an experimental feature of the Android Maps SDK. To build with them, use the following import statement:
import com.mapbox.maps.MapboxExperimental

Adding a basic marker

The simplest way to add a marker is to specify a coordinate:

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.ui.Modifier
import com.mapbox.geojson.Point
import com.mapbox.maps.MapboxExperimental
import com.mapbox.maps.compose.testapp.ExampleScaffold
import com.mapbox.maps.compose.testapp.ui.theme.MapboxMapComposeTheme
import com.mapbox.maps.extension.compose.MapboxMap
import com.mapbox.maps.extension.compose.annotation.Marker

@OptIn(MapboxExperimental::class)
public class MyMapActivity : ComponentActivity() {
  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContent {
      MapboxMapComposeTheme {
        ExampleScaffold {
          MapboxMap(Modifier.fillMaxSize()) {
            Marker(
              point = Point.fromLngLat(-74.0060, 40.7128)
            )
          }
        }
      }
    }
  }
}

Customizing markers

You can customize markers with colors, strokes, and text:

Colors and strokes

MapboxMap(Modifier.fillMaxSize()) {
    Marker(
        point = Point.fromLngLat(-74.0060, 40.7128),
        color = Color.Blue,           // Set the main marker color
        stroke = Color.Magenta,       // Add a stroke color
        innerColor = Color.White      // Set the inner circle color
    )
}

Adding text

MapboxMap(Modifier.fillMaxSize()) {
    Marker(
        point = Point.fromLngLat(-74.0060, 40.7128),
        color = Color.Red,
        text = "New York City"
    )
}

Removing strokes

To remove the stroke, set it to null:

MapboxMap(Modifier.fillMaxSize()) {
    Marker(
        point = Point.fromLngLat(-74.0060, 40.7128),
        stroke = null  // No stroke
    )
}

Adding multiple markers

Use a loop to add multiple markers from a data collection:

data class Location(
    val id: String,
    val coordinate: Point,
    val name: String
)

val locations = listOf(
    Location("1", Point.fromLngLat(-74.0060, 40.7128), "New York"),
    Location("2", Point.fromLngLat(-118.2437, 34.0522), "Los Angeles"),
    // ... more locations
)

MapboxMap(Modifier.fillMaxSize()) {
    locations.forEach { location ->
        Marker(
            point = location.coordinate,
            color = Color.Red,
            text = location.name
        )
    }
}

Removing Markers

When using Jetpack Compose, markers conform to MapContent. Removing them from the MapboxMap composable will also remove them from the visual map. This also works for conditional rendering. The code snippet below uses an if statement and a boolean state variable to control the visibility of a Marker.

var showMarker by remember { mutableStateOf(false) }
MapboxMap(Modifier.fillMaxSize()) {
    if (showMarker) {
      Marker(
          point = Point.fromLngLat(-74.0060, 40.7128),
          stroke = null  // No stroke
      )
    }
}

Performance considerations

Markers create View Annotations with custom text rendering, so performance may degrade with large numbers of markers. For scenarios with 100+ markers, consider:

• Using PointAnnotation instead for better performance
• Using Style Layers for maximum performance with large datasets

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