googlemaps · kikoso · Jan 8, 2026
diff --git a/maps-app/src/main/AndroidManifest.xml b/maps-app/src/main/AndroidManifest.xml
@@ -103,6 +103,9 @@
         <activity
             android:name=".TileOverlayActivity"
             android:exported="true" />
+        <activity
+            android:name=".GroundOverlayActivity"
+            android:exported="true" />
 
         <!-- Used by createComponentActivity() for unit testing -->
         <activity android:name="androidx.activity.ComponentActivity" />

diff --git a/maps-app/src/main/java/com/google/maps/android/compose/BasicMapActivity.kt b/maps-app/src/main/java/com/google/maps/android/compose/BasicMapActivity.kt
@@ -38,12 +38,12 @@ import androidx.compose.foundation.layout.systemBarsPadding
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.layout.wrapContentSize
 import androidx.compose.foundation.shape.RoundedCornerShape
-import androidx.compose.material.Button
-import androidx.compose.material.ButtonDefaults
-import androidx.compose.material.CircularProgressIndicator
-import androidx.compose.material.MaterialTheme
-import androidx.compose.material.Switch
-import androidx.compose.material.Text
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Switch
+import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableIntStateOf
@@ -123,7 +123,7 @@ class BasicMapActivity : ComponentActivity() {
                     ) {
                         CircularProgressIndicator(
                             modifier = Modifier
-                                .background(MaterialTheme.colors.background)
+                                .background(MaterialTheme.colorScheme.background)
                                 .wrapContentSize()
                         )
                     }
@@ -255,8 +255,8 @@ fun GoogleMapView(
 
             Circle(
                 center = circleCenter,
-                fillColor = MaterialTheme.colors.secondary,
-                strokeColor = MaterialTheme.colors.secondaryVariant,
+                fillColor = MaterialTheme.colorScheme.secondary,
+                strokeColor = MaterialTheme.colorScheme.secondary,
                 radius = 1000.0,
             )
 
@@ -400,12 +400,12 @@ private fun MapButton(text: String, onClick: () -> Unit, modifier: Modifier = Mo
     Button(
         modifier = modifier.padding(4.dp),
         colors = ButtonDefaults.buttonColors(
-            backgroundColor = MaterialTheme.colors.onPrimary,
-            contentColor = MaterialTheme.colors.primary
+            containerColor = MaterialTheme.colorScheme.onPrimary,
+            contentColor = MaterialTheme.colorScheme.primary
         ),
         onClick = onClick
     ) {
-        Text(text = text, style = MaterialTheme.typography.body1)
+        Text(text = text, style = MaterialTheme.typography.bodyLarge)
     }
 }
 

diff --git a/maps-app/src/main/java/com/google/maps/android/compose/Demo.kt b/maps-app/src/main/java/com/google/maps/android/compose/Demo.kt
@@ -111,6 +111,11 @@ sealed class ActivityGroup(
                 R.string.tile_overlay_activity_description,
                 TileOverlayActivity::class
             ),
+            Activity(
+                R.string.ground_overlay_activity,
+                R.string.ground_overlay_activity_description,
+                GroundOverlayActivity::class
+            ),
         )
     )
 

diff --git a/maps-app/src/main/java/com/google/maps/android/compose/GroundOverlayActivity.kt b/maps-app/src/main/java/com/google/maps/android/compose/GroundOverlayActivity.kt
@@ -0,0 +1,173 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.maps.android.compose
+
+import android.os.Bundle
+import java.util.Locale
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.systemBarsPadding
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Slider
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Switch
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.google.android.gms.maps.model.BitmapDescriptorFactory
+import com.google.android.gms.maps.model.LatLng
+import com.google.android.gms.maps.model.LatLngBounds
+import com.google.maps.android.compose.theme.MapsComposeSampleTheme
+import androidx.core.graphics.createBitmap
+
+class GroundOverlayActivity : ComponentActivity() {
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        enableEdgeToEdge()
+        setContent {
+            MapsComposeSampleTheme {
+                GroundOverlayScreen()
+            }
+        }
+    }
+}
+
+@Composable
+fun GroundOverlayScreen() {
+    val singapore = LatLng(1.3588227, 103.8742114)
+    val cameraPositionState = rememberCameraPositionState {
+        position = com.google.android.gms.maps.model.CameraPosition.fromLatLngZoom(singapore, 12f)
+    }
+
+    var isVisible by remember { mutableStateOf(true) }
+    var transparency by remember { mutableFloatStateOf(0f) }
+    var bearing by remember { mutableFloatStateOf(0f) }
+
+    val context = androidx.compose.ui.platform.LocalContext.current
+    val imageDescriptor = remember {
+        val drawable = androidx.core.content.ContextCompat.getDrawable(context, R.mipmap.ic_launcher)
+        val bitmap = createBitmap(drawable!!.intrinsicWidth, drawable.intrinsicHeight)
+        val canvas = android.graphics.Canvas(bitmap)
+        drawable.setBounds(0, 0, canvas.width, canvas.height)
+        drawable.draw(canvas)
+        BitmapDescriptorFactory.fromBitmap(bitmap)
+    }
+
+    Box(
+        modifier = Modifier
+            .fillMaxSize()
+            .systemBarsPadding()
+    ) {
+        GoogleMap(
+            modifier = Modifier.fillMaxSize(),
+            cameraPositionState = cameraPositionState
+        ) {
+            // Stable GroundOverlay (using remembered state)
+            GroundOverlay(
+                position = GroundOverlayPosition.create(
+                    LatLngBounds(
+                        LatLng(1.35, 103.86),
+                        LatLng(1.37, 103.88)
+                    )
+                ),
+                image = imageDescriptor,
+                visible = isVisible,
+                transparency = transparency,
+                bearing = bearing
+            )
+
+            // Stress-test GroundOverlay: Re-creating position every recomposition
+            // This would cause a crash/rendering loop if GroundOverlayPosition was not a data class
+            GroundOverlay(
+                position = GroundOverlayPosition.create(
+                    LatLngBounds(
+                        LatLng(1.36, 103.89),
+                        LatLng(1.38, 103.91)
+                    )
+                ),
+                image = imageDescriptor,
+                transparency = 0.5f,
+                zIndex = 1f
+            )
+        }
+
+        Column(
+            modifier = Modifier
+                .align(Alignment.BottomCenter)
+                .fillMaxWidth()
+                .padding(16.dp)
+        ) {
+            GroundOverlayControls(
+                isVisible = isVisible,
+                onVisibilityChange = { isVisible = it },
+                transparency = transparency,
+                onTransparencyChange = { transparency = it },
+                bearing = bearing,
+                onBearingChange = { bearing = it }
+            )
+        }
+    }
+}
+
+@Composable
+fun GroundOverlayControls(
+    isVisible: Boolean,
+    onVisibilityChange: (Boolean) -> Unit,
+    transparency: Float,
+    onTransparencyChange: (Float) -> Unit,
+    bearing: Float,
+    onBearingChange: (Float) -> Unit
+) {
+    Surface(
+        shape = MaterialTheme.shapes.medium,
+        tonalElevation = 4.dp,
+        color = MaterialTheme.colorScheme.surface.copy(alpha = 0.8f),
+        modifier = Modifier.fillMaxWidth()
+    ) {
+        Column(modifier = Modifier.padding(16.dp)) {
+            Row(verticalAlignment = Alignment.CenterVertically) {
+                Text(text = "Visible", modifier = Modifier.weight(1f))
+                Switch(checked = isVisible, onCheckedChange = onVisibilityChange)
+            }
+            Text(text = "Transparency: ${String.format(Locale.getDefault(), "%.2f", transparency)}")
+            Slider(
+                value = transparency,
+                onValueChange = onTransparencyChange,
+                valueRange = 0f..1f
+            )
+            Text(text = "Bearing: ${bearing.toInt()}°")
+            Slider(
+                value = bearing,
+                onValueChange = onBearingChange,
+                valueRange = 0f..360f
+            )
+        }
+    }
+}
diff --git a/.../src/main/java/com/google/maps/android/compose/markerexamples/MarkerClusteringActivity.kt b/.../src/main/java/com/google/maps/android/compose/markerexamples/MarkerClusteringActivity.kt
@@ -2,6 +2,7 @@ package com.google.maps.android.compose.markerexamples
 
 import android.os.Bundle
 import android.util.Log
+import java.util.Locale
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
@@ -17,11 +18,11 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.systemBarsPadding
 import androidx.compose.foundation.shape.CircleShape
-import androidx.compose.material.Button
-import androidx.compose.material.ButtonDefaults
-import androidx.compose.material.MaterialTheme
-import androidx.compose.material.Surface
-import androidx.compose.material.Text
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.SideEffect
@@ -177,7 +178,7 @@ private fun CustomUiClustering(items: List<MyItem>) {
         clusterContent = { cluster ->
             CircleContent(
                 modifier = Modifier.size(40.dp),
-                text = "%,d".format(cluster.size),
+                text = "%,d".format(Locale.getDefault(), cluster.size),
                 color = Color.Blue,
             )
         },
@@ -210,7 +211,7 @@ fun CustomRendererClustering(items: List<MyItem>) {
         clusterContent = { cluster ->
             CircleContent(
                 modifier = Modifier.size(40.dp),
-                text = "%,d".format(cluster.size),
+                text = "%,d".format(Locale.getDefault(), cluster.size),
                 color = Color.Green,
             )
         },
@@ -306,12 +307,12 @@ private fun MapButton(text: String, onClick: () -> Unit, modifier: Modifier = Mo
     Button(
         modifier = modifier.padding(4.dp),
         colors = ButtonDefaults.buttonColors(
-            backgroundColor = MaterialTheme.colors.onPrimary,
-            contentColor = MaterialTheme.colors.primary
+            containerColor = MaterialTheme.colorScheme.onPrimary,
+            contentColor = MaterialTheme.colorScheme.primary
         ),
         onClick = onClick
     ) {
-        Text(text = text, style = MaterialTheme.typography.body1)
+        Text(text = text, style = MaterialTheme.typography.bodyLarge)
     }
 }
 

diff --git a/maps-app/src/main/java/com/google/maps/android/compose/theme/Theme.kt b/maps-app/src/main/java/com/google/maps/android/compose/theme/Theme.kt
@@ -1,9 +1,9 @@
 package com.google.maps.android.compose.theme
 
 import androidx.compose.foundation.isSystemInDarkTheme
-import androidx.compose.material.MaterialTheme
-import androidx.compose.material.darkColors
-import androidx.compose.material.lightColors
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.lightColorScheme
 import androidx.compose.runtime.Composable
 
 @Composable
@@ -12,7 +12,7 @@ fun MapsComposeSampleTheme(
     content: @Composable () -> Unit
 ) {
     MaterialTheme(
-        colors = if (darkTheme) darkColors() else lightColors(),
+        colorScheme = if (darkTheme) darkColorScheme() else lightColorScheme(),
         content = content
     )
 }
diff --git a/maps-app/src/main/res/values/strings.xml b/maps-app/src/main/res/values/strings.xml
@@ -72,6 +72,9 @@
   <string name="tile_overlay_activity">Tile Overlay</string>
   <string name="tile_overlay_activity_description">Adding a tile overlay to the map.</string>
 
+  <string name="ground_overlay_activity">Ground Overlay</string>
+  <string name="ground_overlay_activity_description">Adding a ground overlay to the map.</string>
+
   <!-- Demo group titles -->
   <string name="map_types_title">Map Types</string>
   <string name="map_features_title">Map Features</string>

diff --git a/maps-compose/src/main/java/com/google/maps/android/compose/GroundOverlay.kt b/maps-compose/src/main/java/com/google/maps/android/compose/GroundOverlay.kt
@@ -40,7 +40,8 @@ internal class GroundOverlayNode(
  *
  * Use one of the [create] methods to construct an instance of this class.
  */
-public class GroundOverlayPosition private constructor(
+@ConsistentCopyVisibility
+public data class GroundOverlayPosition internal constructor(
     public val latLngBounds: LatLngBounds? = null,
     public val location: LatLng? = null,
     public val width: Float? = null,
@@ -116,6 +117,11 @@ public fun GroundOverlay(
             update(transparency) { this.groundOverlay.transparency = it }
             update(visible) { this.groundOverlay.isVisible = it }
             update(zIndex) { this.groundOverlay.zIndex = it }
+            update(anchor) {
+                // GroundOverlay does not have a setAnchor method.
+                // We could recreate the overlay here, but that might be expensive.
+                // For now, we'll document that anchor cannot be changed.
+            }
         }
     )
 }