Examples

Adjust a layer's opacity

activity_style_adjust_layer_opacity
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:mapbox="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".examples.styles.AdjustLayerOpacityActivity">
<com.mapbox.mapboxsdk.maps.MapView
android:id="@+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent"
mapbox:mapbox_cameraTargetLat="41.8362"
mapbox:mapbox_cameraTargetLng="-87.6321"
mapbox:mapbox_cameraZoom="9.5"
mapbox:mapbox_cameraZoomMax="13"
mapbox:mapbox_cameraZoomMin="7"
mapbox:mapbox_uiCompassMarginTop="75dp"/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_gravity="top"
android:layout_marginTop="24dp"
android:paddingStart="24dp"
android:paddingLeft="24dp"
android:paddingTop="24dp"
android:paddingEnd="24dp"
android:paddingRight="24dp"
android:paddingBottom="10dp">
<TextView
android:id="@+id/textview_opacity_value"
android:layout_width="45dp"
android:layout_height="wrap_content"
android:text="100%"/>
<SeekBar
android:id="@+id/seek_bar_layer_opacity"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:max="100"
android:progress="100"/>
</LinearLayout>
</FrameLayout>
AdjustLayerOpacityActivity
package com.mapbox.mapboxandroiddemo.examples.styles;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import android.widget.SeekBar;
import android.widget.TextView;
import com.mapbox.mapboxandroiddemo.R;
import com.mapbox.mapboxsdk.Mapbox;
import com.mapbox.mapboxsdk.maps.MapView;
import com.mapbox.mapboxsdk.maps.MapboxMap;
import com.mapbox.mapboxsdk.maps.OnMapReadyCallback;
import com.mapbox.mapboxsdk.maps.Style;
import com.mapbox.mapboxsdk.style.layers.Layer;
import com.mapbox.mapboxsdk.style.layers.RasterLayer;
import com.mapbox.mapboxsdk.style.sources.RasterSource;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.rasterOpacity;
/**
* Use a seekbar to adjust the opacity of a raster layer on top of a map.
*/
public class AdjustLayerOpacityActivity extends AppCompatActivity {
private MapView mapView;
private MapboxMap map;
private Layer chicago;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Mapbox access token is configured here. This needs to be called either in your application
// object or in the same activity which contains the mapview.
Mapbox.getInstance(this, getString(R.string.access_token));
// This contains the MapView in XML and needs to be called after the access token is configured.
setContentView(R.layout.activity_style_adjust_layer_opacity);
final SeekBar opacitySeekBar = findViewById(R.id.seek_bar_layer_opacity);
final TextView percentTextView = findViewById(R.id.textview_opacity_value);
opacitySeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
if (chicago != null) {
chicago.setProperties(
rasterOpacity((float) progress / 100)
);
}
String progressPercentage = progress + "%";
percentTextView.setText(progressPercentage);
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
mapView = findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(new OnMapReadyCallback() {
@Override
public void onMapReady(@NonNull MapboxMap mapboxMap) {
map = mapboxMap;
mapboxMap.setStyle(Style.LIGHT, new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
style.addSource(new RasterSource("chicago-source", "mapbox://mapbox.u8yyzaor"));
style.addLayer(new RasterLayer("chicago", "chicago-source"));
map.getStyle(new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
chicago = style.getLayer("chicago");
}
});
}
});
}
});
}
@Override
public void onResume() {
super.onResume();
mapView.onResume();
}
@Override
protected void onStart() {
super.onStart();
mapView.onStart();
}
@Override
protected void onStop() {
super.onStop();
mapView.onStop();
}
@Override
public void onPause() {
super.onPause();
mapView.onPause();
}
@Override
public void onLowMemory() {
super.onLowMemory();
mapView.onLowMemory();
}
@Override
protected void onDestroy() {
super.onDestroy();
mapView.onDestroy();
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mapView.onSaveInstanceState(outState);
}
}
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