Show a callout with the latitude and longitude of user-tapped points.
Use case
Callouts are used to display temporary detail content on a map. You can display text and arbitrary UI controls in callouts.
How to use the sample
Tap anywhere on the map. A callout showing the WGS84 coordinates for the tapped point will appear.
How it works
- When the user taps, get the tapped location(map point) from the
SingleTapConfirmedEvent
. - Project the point's geometry to WGS84 using
GeometryEngine.projectOrNull(mapPoint, SpatialReference.wgs84())
. - Create a new Android TextView object and set its text to the coordinate string from the point.
- Show the
Callout
on the map view usingmapView.callout.show()
which takes the above created View and WGS84 point as parameters. - Center the map on the tapped location using
mapView.setViewpointCenter
.
Relevant API
- Callout
- GeometryEngine
- MapView
- Point
Tags
balloon, bubble, callout, flyout, flyover, info window, popup, tap
Sample Code
/* Copyright 2023 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.showcallout
import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.runtime.Composable
import com.arcgismaps.ApiKey
import com.arcgismaps.ArcGISEnvironment
import com.esri.arcgismaps.sample.sampleslib.theme.SampleAppTheme
import com.esri.arcgismaps.sample.showcallout.screens.MainScreen
class MainActivity : ComponentActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// authentication with an API key or named user is
// required to access basemaps and other location services
ArcGISEnvironment.apiKey = ApiKey.create(BuildConfig.API_KEY)
setContent {
SampleAppTheme {
ShowCalloutApp()
}
}
}
@Composable
private fun ShowCalloutApp() {
Surface(
color = MaterialTheme.colorScheme.background
) {
MainScreen(
sampleName = getString(R.string.app_name),
application = application
)
}
}
}