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
ArcGISMapImageLayer
object 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
// 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);
}
}
}