Change the visibility of sublayers.
      
  
    
Use case
A map image layer may contain many sublayers such as different types of roads in a road network or city, county, and state borders in a US map. The user may only be interested in a subset of these sublayers. Or, perhaps showing all of the sublayers would show too much detail. In these cases, you can hide certain sublayers by changing their visibility.
How to use the sample
Each sublayer has a check box which can be used to toggle the visibility of the sublayer.
How it works
- Create an 
ArcGISMapImageLayerobject with the URL to a map image service. - Get the list of sublayers with 
mapImageLayer.Sublayers. - For each layer in the sublayer list, set its visible property to true or false.
 
Relevant API
- ArcGISMapImageLayer
 
Tags
layers, sublayers, visibility
Sample Code
ChangeSublayerVisibility.cs
// Copyright 2016 Esri.
//
// 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.
using Android.App;
using Android.OS;
using Android.Views;
using Android.Widget;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.UI.Controls;
using System;
using System.Linq;
namespace ArcGISRuntime.Samples.ChangeSublayerVisibility
{
    [Activity (ConfigurationChanges=Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        name: "Map image layer sublayer visibility",
        category: "Layers",
        description: "Change the visibility of sublayers.",
        instructions: "Each sublayer has a check box which can be used to toggle the visibility of the sublayer.",
        tags: new[] { "layers", "sublayers", "visibility" })]
    public class ChangeSublayerVisibility : Activity
    {
        // Hold a reference to the map view
        private MapView _myMapView;
        // Hold reference to image layer for easier access to sublayers
        private ArcGISMapImageLayer _imageLayer;
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            Title = "Change sublayer visibility";
            // Create the UI, setup the control references and execute initialization
            CreateLayout();
            Initialize();
        }
        private void Initialize()
        {
            // Create new Map
            Map myMap = new Map();
            // Create uri to the map image layer
            Uri serviceUri = new Uri(
               "https://sampleserver6.arcgisonline.com/arcgis/rest/services/SampleWorldCities/MapServer");
            // Create new image layer from the url
            _imageLayer = new ArcGISMapImageLayer(serviceUri)
            {
                Name = "World Cities Population"
            };
            // Add created layer to the basemaps collection
            myMap.Basemap.BaseLayers.Add(_imageLayer);
            // Assign the map to the MapView
            _myMapView.Map = myMap;
        }
        private async void OnSublayersClicked(object sender, EventArgs e)
        {
            try
            {
                // Make sure that layer and it's sublayers are loaded
                // If layer is already loaded, this returns directly
                await _imageLayer.LoadAsync();
                Button sublayersButton = (Button)sender;
                // Create menu to change sublayer visibility
                PopupMenu sublayersMenu = new PopupMenu(this, sublayersButton);
                sublayersMenu.MenuItemClick += OnSublayersMenuItemClicked;
                // Create menu options
                foreach (ArcGISSublayer sublayer in _imageLayer.Sublayers)
                    sublayersMenu.Menu.Add(sublayer.Name);
                // Set values to the menu items
                for (int i = 0; i < sublayersMenu.Menu.Size(); i++)
                {
                    IMenuItem menuItem = sublayersMenu.Menu.GetItem(i);
                    // Set menu item to contain checkbox
                    menuItem.SetCheckable(true);
                    // Set default value
                    menuItem.SetChecked(_imageLayer.Sublayers[i].IsVisible);
                }
                // Show menu in the view
                sublayersMenu.Show();
            }
            catch (Exception ex)
            {
                new AlertDialog.Builder(this).SetMessage(ex.ToString()).SetTitle("Error").Show();
            }
        }
        private void OnSublayersMenuItemClicked(object sender, PopupMenu.MenuItemClickEventArgs e)
        {
            // Change the checked value
            e.Item.SetChecked(!e.Item.IsChecked);
            // Get title from the selected item
            string selectedSublayerTitle = e.Item.TitleCondensedFormatted.ToString();
            // Get index that is used to get the selected url
            ArcGISSublayer sublayer = _imageLayer.Sublayers.First(x => x.Name == selectedSublayerTitle);
            sublayer.IsVisible = e.Item.IsChecked;
        }
        private void CreateLayout()
        {
            // Create a new vertical layout for the app
            LinearLayout layout = new LinearLayout(this) { Orientation = Orientation.Vertical };
            // Create button to show possible map options
            Button mapsButton = new Button(this)
            {
                Text = "Sublayers"
            };
            mapsButton.Click += OnSublayersClicked;
            // Add maps button to the layout
            layout.AddView(mapsButton);
            // Add the map view to the layout
            _myMapView = new MapView(this);
            layout.AddView(_myMapView);
            // Show the layout in the app
            SetContentView(layout);
        }
    }
}