I’m thinking to check on write helpful information application for Android. There’s however something I buy confused.

From android document. I recognize that folks must have an API to get the cell phone location?

This is exactly what I buy confused:

1. Is employing Mobile’s Gps navigation navigation navigation is provided for free? (That’s mean I’d able to write a application which uses the Gps navigation navigation navigation to obtain the mobile location without requiring internet)
2. I do not actually know how Google Map have API restriction due to data right. What’s that data right? Basically write helpful information application which uses Gps navigation navigation navigation, does affecting me too?

requested Apr 28 ’11 at 14:02

1. When using the mobile Gps navigation navigation navigation is provided for free. It’s like any other services provided with the OS. The simple truth is based on the Android device.
2. Google Maps API has certain limitations on ways to use the map data, the geocoding data they provide along with other stuff too. For instance, you can’t show introduced on by geocoding searches without showing a Google Map on a single screen. The map images cannot be helpful for commercial purposes outdoors the API. For ex. printing the pictures and selling them separate maps.

The restrictions affect you if you use the Maps API. What application considering building though?

clarified Apr 28 ’11 at 14:12

What can i be not when using the Google Map API? I’m thinking to create someone to keep things interesting to check out learn writing some Android Application. See whether is possible to condition i.e capture some map images from google or from somewhere into image files (or say make my very own, personal map image), store towards the dental appliance map the co-ordinates for that map images, then all We used is just the Gps navigation navigation navigation to obtain the co-ordinates.

Will the restrictions affect me too? King Apr 28 ’11 at 14:29

You can’t make use of the Google Map images outdoors within the API. When you’re getting images from elsewhere legally, you’ll be able to map the geopoints inside the geocoding plan to your images. Technique consumer’s location permission is granted using the user themselves instead of intermediary. You however desire to use it responsibly. ) Abhinav Apr 28 ’11 at 14:32

You are getting the co-ordinates without online. Converting this having a home address, or getting map tiles, will need access to the internet.

The information right may be the possession/licensing within the data. For instance DVD, a distributor in a single region is licensed using the holder to advertise a replica. You’ve different legal legal legal rights for that distributor, that has different legal legal legal rights for that holder.

Key classes

Note: The process described during this guide modify the working platform location API in android.location. Google’s Location Services API, a part of Google Play Services, provides a more effective, high-level framework that instantly handles location providers, user movement, and precision. In addition, it handles location update scheduling according to power consumption parameters you provide. Generally, you are getting better battery performance, furthermore to appropriate precision, while using the Location Services API.

For more information on the region Services API, see Google Location Services for Android.

Knowing in which the user is enables the application form to obtain smarter and deliver better information for that user. When making a place-aware application for Android, you may use Gps navigation navigation navigation and Android’s Network Location Provider to get the user location. Although Gps navigation navigation navigation is most accurate, it really works outdoors, it rapidly consumes battery power, and does not return the region as rapidly as users want. Android’s Network Location Provider determines user location using cell tower and Wi-Fi signals, offering location information in a way that works inside and outdoors of doorways, responds faster, and uses less battery power. To get the user location in your application, you should utilize both Gps navigation navigation navigation along with the Network Location Provider, or simply one.

Challenges in Exercising User Location

Acquiring user location within the mobile phone may be complicated. There are numerous primary explanations why a location studying (whatever the source) can contain errors and become inaccurate. Some causes of error within the user location include:

• Many location sources

Gps navigation navigation navigation, Cell-ID, and Wi-Fi can each give a clue to users location. Exercising which to make use of and trust relies on trade-offs in precision, speed, and battery-efficiency.

Since the user location changes, you’ve to consider movement by re-estimating user location from time to time.

Location estimates via each location source aren’t consistent in their precision. A location acquired 10-seconds ago in one source is much more accurate in comparison with newest location from another or same source.

These problems helps it be nearly impossible to find a reliable user location studying. This document provides information that will assist you meet these challenges to obtain a reliable location studying. In addition, it provides ideas you can use in your application to supply the client through getting an exact and responsive geo-location experience.

Requesting Location Updates

Before addressing a few in the location errors described above, here’s presenting the simplest way to obtain user location on Android.

Getting user location in Android works by way of callback. You indicate that you want to acquire location updates inside the LocationManager (“Location Manager”) by calling requestLocationUpdates(). passing it a LocationListener. Your LocationListener must implement several callback techniques the area Manager calls once the user location changes or once the status within the service changes.

For instance, the next code shows the easiest method to define a LocationListener and ask for location updates:

The first parameter in requestLocationUpdates() is the kind of location provider to make use of (during this situation, the Network Location Provider for cell tower and Wi-Fi based location). You can control how frequently where your listener receives updates while using the second and third parametersecond may be the minimum time interval between notifications along with the third may be the minimum difference in distance between notificationssetting both to zero demands location notifications as much as you can. The best parameter could be the LocationListener. which receives callbacks for location updates.

To request location updates inside the Gps navigation navigation navigation provider, use Gps navigation navigation navigation_PROVIDER instead of NETWORK_PROVIDER. You may also request location updates from both Gps navigation navigation navigation along with the Network Location Provider by calling requestLocationUpdates() two occasionsonce for NETWORK_PROVIDER then when for Gps navigation navigation navigation_PROVIDER .

Requesting User Permissions

To be able to receive location updates from NETWORK_PROVIDER or Gps navigation navigation navigation_PROVIDER. you have to request anyone’s permission by declaring either the ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission, correspondingly, in your Android manifest file. Without these permissions, the application form will fail at runtime when requesting location updates.

If you are using both NETWORK_PROVIDER and Gps navigation navigation navigation_PROVIDER. you will have to request just the ACCESS_FINE_LOCATION permission, since it includes permission for providers. Permission for ACCESS_COARSE_LOCATION enables access simply to NETWORK_PROVIDER.

Caution: In situation the applying targets Android 5. (API level 21) or greater, you have to think that the applying uses the android.hardware.locationwork or android.hardware.location.gps navigation navigation navigation hardware feature within the manifest file, based on if the application receives location updates from NETWORK_PROVIDER or from Gps navigation navigation navigation_PROVIDER. In situation the applying receives location information from either of people location provider sources, you have to think that the application form uses these hardware features in your application manifest. On devices running verions before Android 5. (API 21), requesting the ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION permission includes an implied request location hardware features. However, requesting individuals permissions doesn’t instantly request location hardware features on Android 5. (API level 21) and greater.

The next code sample helps demonstrate to declare the permission and hardware feature within the manifest file in the application that reads data inside the device’s Gps navigation navigation navigation:

Defining one for the greatest Performance

Location-based applications are actually commonplace, but because of the under optimal precision, user movement, the numerous methods for getting the area, along with the need to conserve battery, getting user location is complicated. To overcome the obstacles of acquiring a great user location while preserving battery power, you have to define an ordinary model that specifies the means by that the application obtains the client location. This model includes when you begin and prevent listening for updates when to make use of cached location data.

Flow for acquiring user location

This really is frequently an average flow of procedures for acquiring the client location:

1. Start application.
2. Sometime later, start listening for updates from preferred location providers.
3. Have a “current best estimate” of location by filtering out new, but less accurate fixes.
4. Stop listening for location updates.
5. Make use of the last best location estimate.

Figure 1 demonstrates this model within the timeline that visualizes time by which a credit card applicatoin is listening for location updates along with the occasions which exist for the reason that point.

Figure 1. Some time representing from the question by which a credit card applicatoin listens for location updates.

This sort of a windowwhere location updates are receivedframes a lot of the decisions make when adding location-based services for that application.

Deciding when you begin listening for updates

You might want to start listening for location updates once your application starts, or after users activate a particular feature. Bear in mind that extended home home home windows of listening for location fixes can overindulge of electrical batteries, but short periods may not permit sufficient precision.

As proven above, you can start listening for updates by calling requestLocationUpdates() :

Obtaining a simple option while using the last known location

Who’s requires for your location listener to get the initial location fix is frequently too extended for users wait. Until a much more accurate location is supplied for that location listener, you can utilize a cached location by calling getLastKnownLocation(String) :

Deciding whenever you stop listening for updates

The logic of deciding when new fixes aren’t necessary might vary from quite simple to very complex using the application. A brief gap between once the location is acquired when the region can be utilized, enhances the precision within the estimate. Always beware that listening for almost any extended time consumes lots of battery power, then when you possess the data, you need to stop listening for updates by calling removeUpdates(PendingIntent) :

Maintaining a present best estimate

You can anticipate the most recent location fix is considered because the accurate. However, since the precision in the location fix varies, the newest fix isn’t necessarily the very best. You need to include logic for selecting location fixes according to several criteria. The factors also varies according to the use-cases of the approval and field testing.

The following are a few things you can do to validate the reality in the location fix:

• Determine whether the region retrieved is considerably newer in comparison with previous estimate.
• Determine whether the reality claimed using the location is more preferable or worse in comparison with previous estimate.
• Check which provider the brand-new location arises from and discover in case you trust it more.

An intricate demonstration of this logic look similar to this:

Modifying the model in order to save battery and understanding exchange

When you develop application, you will probably uncover the model for offering good location and good performance needs some adjustment. Right here are a handful of products you may switch to uncover a great balance backward and forward.

A smaller sized sized sized window that you just listen for location updates means less interaction with Gps navigation navigation navigation and network location services, thus, preserving battery existence. It enables in a lower cost locations to pick from a finest estimate.

Reducing the rate where new updates appear with the window will frequently increase battery efficiency, but at the cost of precision. The requirement of the trade-off is dependent upon the means by that the application can be utilized. You can reduce the rate of updates by growing the parameters in requestLocationUpdates() that specify the interval serious amounts of minimum distance change.

According to the atmosphere where the application can be utilized or possibly the most well-liked quantity of precision, you can easily make use of the Network Location Provider or only Gps navigation navigation navigation, instead of both. Reaching only among the services reduces battery usage in the potential price of precision.

Common application cases

A lot of you might want to hold the user location in your application. Right here are a handful of scenarios in you should use the client place to enhance the application form. Each scenario also describes good practices whenever you stop and start listening for the location, to acquire a great studying that assist preserve battery existence.

Tagging user-produced happy with a location

You may be developing a credit card applicatoin where user-produced posts are tagged getting a place. Consider users discussing their local encounters, posting an exam for almost any restaurant, or recording some content which can be augmented employing their current location. Among methods this interaction can happen, based on the location services, is visualized in figure 2.

Figure 2. Some time representing from the question where the user location is acquired and listening stops once the user consumes the present location.

This lines an eye on the final type of how user location is acquired in code (figure 1). To get the best location precision, you could begin listening for location updates when users begin allowing the data or possibly in situation the application starts, then stop listening for updates when content has the ability to be printed or recorded. You might want to consider how extended an average task of making the information takes and select once the duration enables for efficient selection of a location estimate.

Increasing the user choose what direction to go

You may be developing a credit card applicatoin that tries to provide users having a couple of options on how to proceed. For instance, you are searching to supply all the nearby restaurants, stores, and entertainment along with the order of recommendations changes according to the user location.

To assist this sort of flow, you are able to:

• Arrange recommendations every time a new best estimate is acquired
• Stop listening for updates when the order of recommendations has stabilized

This kind of model is visualized in figure 3.

Figure 3. Some time representing from the question where a dynamic quantity of facts are updated every time the client location updates.

Offering Mock Location Data

Whenever you get the application, you’ll certainly have to test precisely how your model for acquiring user location works. This is often most easily done having a real Android-powered device. If, however, you do not have a musical instrument, you’ll probably still test out your location-based features by mocking location data within the Android emulator. You will find three new techniques to send the application form mock location data: using Android Studio, DDMS, or possibly the “geo” command within the emulator console.

Note: Offering mock location facts are injected as Gps navigation navigation navigation location data, therefore you must request location updates from Gps navigation navigation navigation_PROVIDER to make certain that mock location data to operate.

Using Android Studio

Select Tools Android AVD Manager. Within the Android Virtual Device Manager window, choose your AVD and launch it within the emulator by choosing the eco-friendly play arrow within the Actions column.

Then, select Tools Android Android Device Monitor. Select the Emulator Control tab within the Android Device Monitor window, and enter Gps navigation navigation navigation coordinates under Location Controls as individual lat/extended coordinates, obtaining a GPX submit an application for route playback, or maybe a KML submit an application for multiple place marks.

Using DDMS

While using the DDMS tool, you can simulate location data a couple of different ways:

• By hands send individual longitude/latitude coordinates for that device.
• Use a GPX file describing a route for playback for that device.
• Use a KML file describing individual place marks for sequenced playback for that device.

To understand more about using DDMS to spoof location data, see Using DDMS.

When using the “geo” command within the emulator console

To provide mock location data inside the command line:

1. Launch the application form within the Android emulator and open a terminal/console in your SDK’s /tools directory.
2. Communicate with the emulator console:
3. Send the region data:

• geo fix to provide a group geo-location.

This command accepts a longitude and latitude in decimal levels, along with an optional altitude in meters. For instance: