Display a file with a KML network link, including displaying any network link control messages at launch.
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
- Create a
KmlDatasetfrom a KML source which has network links. - Construct a
KmlLayerwith the dataset and add the layer as an operational layer withScene.operationalLayers.add(kmlLayer). - To listen for network messages, collect them from
KmlDataset.kmlNetworkLinkMessageReceived.
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. This sample uses the GeoView-Compose Toolkit module to be able to implement a composable SceneView.
Tags
geoview-compose, keyhole, KML, KMZ, network link, network link control, OGC
Sample Code
/* Copyright 2024 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.arcgismaps.sample.addkmllayerwithnetworklinks.components
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
import android.app.Application
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.viewModelScope
import com.arcgismaps.mapping.ArcGISScene
import com.arcgismaps.mapping.BasemapStyle
import com.arcgismaps.mapping.Viewpoint
import com.arcgismaps.mapping.kml.KmlDataset
import com.arcgismaps.mapping.layers.KmlLayer
import com.esri.arcgismaps.sample.sampleslib.components.MessageDialogViewModel
class SceneViewModel(application: Application) : AndroidViewModel(application) {
// create a KML dataset from a URL, then use it to create a KML layer
private val kmlDataset = KmlDataset("https://www.arcgis.com/sharing/rest/content/items/600748d4464442288f6db8a4ba27dc95/data")
private val kmlLayer = KmlLayer(kmlDataset)
// create a scene with the imagery basemap, centred over Germany and the Netherlands
val scene = ArcGISScene(BasemapStyle.ArcGISImagery).apply {
initialViewpoint = Viewpoint(52.0, 7.0, 8_000_000.0)
}
// create a ViewModel to handle dialog interactions
val messageDialogVM: MessageDialogViewModel = MessageDialogViewModel()
init {
viewModelScope.launch(Dispatchers.Main) {
// show a popup when any network link messages are received
kmlDataset.kmlNetworkLinkMessageReceived.collect {
messageDialogVM.showMessageDialog(
title = "KML Network Link Message",
description = it.message
)
}
}
viewModelScope.launch(Dispatchers.IO) {
// wait for the KML layer to load, then add it to the scene view
kmlLayer.load().onSuccess {
scene.operationalLayers.add(kmlLayer)
}.onFailure { error ->
// report errors if the KML layer failed to load
messageDialogVM.showMessageDialog(
title = "Error",
description = error.message.toString()
)
}
}
}
}