Display KML network links

View on GitHub
Sample viewer app

Display a file with a KML network link, including displaying any network link control messages at launch.

Image of display KML network links

Use case

KML files can reference other KML files on the network and support automatically refreshing content. For example, survey workers will benefit from KML data shown on their devices automatically refreshing to show the most up-to-date state. Additionally, discovering KML files linked to the data they are currently viewing provides additional information to make better decisions in the field.

How to use the sample

The sample will load the KML file automatically. The data shown should refresh automatically every few seconds. Pan and zoom to explore the map.

How it works

  1. Create a KmlDataset from a KML source which has network links.
  2. Construct a KmlLayer with the dataset and add the layer as an operational layer with MapView.getMap().getOperationalLayers().add(kmlLayer).
  3. To listen for network messages, add a KmlNetworkLinkMessageReceivedListener on the dataset.

Relevant API

  • KmlDataset
  • KmlLayer

About the data

This map shows the current air traffic in parts of Europe with heading, altitude, and ground speed. Additionally, noise levels from ground monitoring stations are shown.

Tags

keyhole, KML, KMZ, network link, network link control, OGC

Sample Code

MainActivity.java
                                                                                                     
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
/* 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.
 *
 */

package com.esri.arcgisruntime.sample.displaykmlnetworklinks;

import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;
import com.esri.arcgisruntime.ArcGISRuntimeEnvironment;
import com.esri.arcgisruntime.layers.KmlLayer;
import com.esri.arcgisruntime.loadable.LoadStatus;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.BasemapStyle;
import com.esri.arcgisruntime.mapping.Viewpoint;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.ogc.kml.KmlDataset;

public class MainActivity extends AppCompatActivity {

  private static final String TAG = MainActivity.class.getSimpleName();

  private MapView mMapView;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // authentication with an API key or named user is required to access basemaps and other
    // location services
    ArcGISRuntimeEnvironment.setApiKey(BuildConfig.API_KEY);

    // get the reference to the map view
    mMapView = findViewById(R.id.mapView);
    // create a map with the dark gray canvas basemap
    ArcGISMap map = new ArcGISMap(BasemapStyle.ARCGIS_DARK_GRAY);
    // set the map to the map view
    mMapView.setMap(map);
    mMapView.setViewpoint(new Viewpoint(51.960403, 10.029217, 10000000));

    // create a kml data set from a URL
    KmlDataset kmlDataset = new KmlDataset(getString(R.string.european_air_traffic_kml_url));
    // show an alert when any network link messages are received
    kmlDataset.addKmlNetworkLinkMessageReceivedListener(kmlNetworkLinkMessageReceivedEvent -> {
      String message = "KML Network Link Message: " + kmlNetworkLinkMessageReceivedEvent.getMessage();
      Toast.makeText(this, message, Toast.LENGTH_LONG).show();
      Log.i(TAG, message);
    });

    // a KML layer created from a remote KML file
    KmlLayer kmlLayer = new KmlLayer(kmlDataset);

    // clear the existing layers from the map
    mMapView.getMap().getOperationalLayers().clear();

    // add the KML layer to the map as an operational layer.
    mMapView.getMap().getOperationalLayers().add(kmlLayer);

    // report errors if failed to load
    kmlDataset.addDoneLoadingListener(() -> {
      if (kmlDataset.getLoadStatus() != LoadStatus.LOADED) {
        String error = "Failed to load kml layer from URL: " + kmlDataset.getLoadError().getMessage();
        Toast.makeText(this, error, Toast.LENGTH_LONG).show();
        Log.e(TAG, error);
      }
    });
  }

  @Override
  protected void onPause() {
    mMapView.pause();
    super.onPause();
  }

  @Override
  protected void onResume() {
    super.onResume();
    mMapView.resume();
  }

  @Override
  protected void onDestroy() {
    mMapView.dispose();
    super.onDestroy();
  }
}

Your browser is no longer supported. Please upgrade your browser for the best experience. See our browser deprecation post for more details.