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The following snippet shows how to implement the LocationCallback interface and define the method, then get the timestamp of the location update and display the latitude, longitude and timestamp on your app's user interface:. Consider whether you want to stop the location updates when the activity is no longer in focus, such as when the user switches to another app or to a different activity in the same app.
This can be handy to reduce power consumption, provided the app doesn't need to collect information even when it's running in the background. This section shows how you can stop the updates in the activity's onPause method. To stop location updates, call removeLocationUpdates , passing it a LocationCallback , as shown in the following code sample:.
Use a boolean, requestingLocationUpdates , to track whether location updates are currently turned on. In the activity's onResume method, check whether location updates are currently active, and activate them if not:. A change to the device's configuration, such as a change in screen orientation or language, can cause the current activity to be destroyed. Your app must therefore store any information it needs to recreate the activity. One way to do this is via an instance state stored in a Bundle object.
The following code sample shows how to use the activity's onSaveInstanceState callback to save the instance state:. Define an updateValuesFromBundle method to restore the saved values from the previous instance of the activity, if they're available.
Call the method from the activity's onCreate method, as shown in the following code sample:. For more about saving instance state, see the Android Activity class reference. Note: For a more persistent storage, you can store the user's preferences in your app's SharedPreferences. Set the shared preference in your activity's onPause method, and retrieve the preference in onResume. For more information about saving preferences, read Saving Key-Value Sets. An example of an app that allows the app to continue a user-initiated action without requesting all-the-time access to background location.
An example of an app that requests access to background location. Content and code samples on this page are subject to the licenses described in the Content License. App Basics. Build your first app. App resources. Resource types. App manifest file. Device compatibility.
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Navigation component. App links. Dependency injection. Core topics. App compatibility. Interact with other apps. Package visibility. Intents and intent filters. User interface. Add motion to your layout with MotionLayout. MotionLayout XML reference. Improving layout performance. Custom view components. Look and feel. Splash screens. Add the app bar. Control the system UI visibility. Supporting swipe-to-refresh.
Pop-up messages overview. Adding search functionality. Creating backward-compatible UIs. Home channels for mobile apps. App widgets. Media app architecture. Building an audio app. Building a video app. The Google Assistant.
Routing between devices. Background tasks. Manage device awake state.
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