Display a tiled web layer.
Use case
Tiled map services are a set of pre-generated images (e.g. "tiles") arranged in folders for each row, column, and zoom level. As you navigate the map, map tiles are requested for the current extent. ArcGISTiledLayer
and WMTSLayer
are types of tiled map services used for specific data types. WebTiledLayer
is useful for displaying other data sources that contain tiles arranged in a row/column/level directory structure, such as OpenStreetMap.
How to use the sample
Run the sample and a map will appear. As you navigate the map, map tiles will be fetched automatically and displayed on the map.
How it works
- Create a
WebTiledLayer
from a URL and a list of subdomains. - Create a new
Basemap
from the layer. - Update the attribution on the layer. Note: this is a necessary step because web tiled services don't have associated service metadata.
- Display the basemap.
Relevant API
- Basemap
- WebTiledLayer
About the data
The basemap in this sample is provided by Stamen Design. Stamen publishes tiled services based on OpenStreetMap data with several unique styles applied.
Additional information
Web tiled services use a uniform addressing scheme with pre-rendered tiles. Image tiles are accessed via a URL template string, with parameters for subdomain, level, column, and row.
- Subdomain is optional and allows Runtime to balance requests among multiple servers for enhanced performance.
- Level, row, and column select the tiles to load based on the visible extent of the map.
For more information about web tiled layers, see the following resources:
Tags
layer, OGC, Open Street Map, OpenStreetMap, stamen.com, tiled, tiles
Sample Code
// Copyright 2018 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.Widget;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.UI.Controls;
using System.Collections.Generic;
using System.Threading.Tasks;
namespace ArcGISRuntime.Samples.LoadWebTiledLayer
{
[Activity (ConfigurationChanges=Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
[ArcGISRuntime.Samples.Shared.Attributes.Sample(
name: "Web tiled layer",
category: "Layers",
description: "Display a tiled web layer.",
instructions: "Run the sample and a map will appear. As you navigate the map, map tiles will be fetched automatically and displayed on the map.",
tags: new[] { "OGC", "Open Street Map", "OpenStreetMap", "layer", "stamen.com", "tiled", "tiles" })]
public class LoadWebTiledLayer : Activity
{
// Create and hold reference to the used MapView
private MapView _myMapView;
// Templated URL to the tile service
private readonly string _templateUri = "https://stamen-tiles-{subdomain}.a.ssl.fastly.net/watercolor/{level}/{col}/{row}.jpg";
// List of subdomains for use when constructing the web tiled layer
private readonly List<string> _tiledLayerSubdomains = new List<string> { "a", "b", "c", "d" };
// Attribution string for the Stamen service
private readonly string _attribution = "Map tiles by Stamen Design, under CC BY 3.0. Data by OpenStreetMap, under CC BY SA.";
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
Title = "Web tiled layer";
// Create the UI, setup the control references and execute initialization
CreateLayout();
Initialize();
}
private void Initialize()
{
// Create the layer from the URL and the subdomain list
WebTiledLayer myBaseLayer = new WebTiledLayer(_templateUri, _tiledLayerSubdomains);
// Create a basemap from the layer
Basemap layerBasemap = new Basemap(myBaseLayer);
// Apply the attribution for the layer
myBaseLayer.Attribution = _attribution;
// Create a map to hold the basemap
Map myMap = new Map(layerBasemap);
// Add the map to the map view
_myMapView.Map = myMap;
}
private void CreateLayout()
{
// Create a new vertical layout for the app
LinearLayout layout = new LinearLayout(this) { Orientation = Orientation.Vertical };
// Add the map view to the layout
_myMapView = new MapView(this);
layout.AddView(_myMapView);
// Show the layout in the app
SetContentView(layout);
}
}
}