When do I need android.hardware.location.gps and a

2019-01-31 07:10发布

问题:

Google is informing by email of changes to the Android location permissions:

We’re making a change on October 15th, 2016 that will affect apps targeting API version 21 (Android 5.0, Lollipop) or higher that use ACCESS_FINE_LOCATION but don't explicitly have the "android.hardware.location.gps" uses-feature. Going forward, these apps will be available to install on devices that don't have GPS hardware. In most cases this won't be an issue since Wi-Fi and Cell-ID based location provides high enough fidelity for the typical operation of these apps. However, any apps that require GPS hardware, such as GPS navigators, should explicitly add the "android.hardware.location.gps" uses-feature to their manifest.

If your app requires GPS to function properly and you do not include in your manifest declaration, your users may have a poor app experience.

Also, if you’re using the fused location provider and wish to receive the most accurate location samples from GPS (i.e. with PRIORITY_HIGH_ACCURACY), you must include the "android.hardware.location.gps" feature in your app’s manifest to ensure that Google Play only distributes your app to devices with GPS sensors.

You can read more about this change in the Android Developers Help Center.

From the Android Developers Help Center

In order to receive location updates from NETWORK_PROVIDER or GPS_PROVIDER, you must request the user's permission by declaring either the ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission, respectively, in your Android manifest file. Without these permissions, your application will fail at runtime when requesting location updates.

If you are using both NETWORK_PROVIDER and GPS_PROVIDER, then you need to request only the ACCESS_FINE_LOCATION permission, because it includes permission for both providers. Permission for ACCESS_COARSE_LOCATION allows access only to NETWORK_PROVIDER.

Caution: If your app targets Android 5.0 (API level 21) or higher, you must declare that your app uses the android.hardware.location.network or android.hardware.location.gps hardware feature in the manifest file, depending on whether your app receives location updates from NETWORK_PROVIDER or from GPS_PROVIDER. If your app receives location information from either of these location provider sources, you need to declare that the app uses these hardware features in your app manifest. On devices running verions prior to Android 5.0 (API 21), requesting the ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION permission includes an implied request for location hardware features. However, requesting those permissions does not automatically request location hardware features on Android 5.0 (API level 21) and higher.

I am using the fused location provider, targeting API 21, and using ACCESS_FINE_LOCATION. I don't specifically care whether GPS is available, only that the most accurate location is reported.

  • Based on the first quotation, I think I do not have to make any changes.
  • Based on the second quotation, I think I need both android.hardware.location.gps and android.hardware.location.network. Or is this only for LocationManager and not fused location?

Do I need android.hardware.location.gps and android.hardware.location.network or not?

回答1:

The second quotation is telling you that you need either android.hardware.location.network or android.hardware.location.gps, if you specifically need one or the other location provider.

If you want updates via GPS, you need android.hardware.location.gps. If you want updates via the WiFi and cellular networks, you need android.hardware.location.network.

If you want updates from both the network and GPS, you should include both <uses-feature> elements.

If you don't specify either, your device may be installed on devices without that provider. For example, it may be installed on a device without a GPS, cellular network, or Wi-Fi chip.

In other words, getting location requires either the network location feature or the GPS feature. If you don't declare that your application needs one or the other, you may not get location updates at all.

API 21 vs 20 and below

Note that the above is only true for API 21 and above. Prior to API 21, requesting the ACCESS_COARSE_LOCATION permission implied the location.network feature, wheras requesting ACCESS_FINE_LOCATION implied the location.gps feature (see <uses-feature>).

The only change right now is that, for API 21+, any app requesting ACCESS_FINE_LOCATION will soon be available to install on devices without GPS. If your app previously assumed GPS was available (and needs GPS), you need to make sure you have the explicit request for android.hardware.location.gps.

Google says that network location providers are now good enough for a fine location, thus, the change.



回答2:

TL;DR: No, you don't have to add uses-feature to your manifest, but depending, you might.

complete answer:

uses-feature of the manifest is only so that Google Play can filter out devices that does not contain a feature that is necessary for the application to execute correctly. (Examples are GPS for a turn-by-turn navigation app, or Camera for a camera app).

Read carefully this quote:

any apps that require GPS hardware, such as GPS navigators, should explicitly add the "android.hardware.location.gps" uses-feature to their manifest

(...)

and wish to receive the most accurate location samples from GPS

As you mention, you only care that the FusedLocationProvider gives you the best location available to the device is installed. That means, even though you're requesting PRIORITY_HIGH_ACCURACY, your app might get installed on devices that does not contain GPS and will never get a location as accurate as a GPS, or maybe even (in some very rare odd case), be installed on device that does not contain any location provider.

edit:

Based on the second quotation, I think I need both android.hardware.location.gps and android.hardware.location.network. Or is this only for LocationManager and not fused location?

I just went digging on the docs https://developer.android.com/guide/topics/manifest/uses-feature-element.html#hw-features and found it very interesting, there're 3 possibilities:

  • android.hardware.location
  • android.hardware.location.gps
  • android.hardware.location.network

so based on that, if your application cannot work without any form of location you should use the first one android.hardware.location, else, if your app uses location but it's not essential to its funcionality, you can be free to not include anything



回答3:

Quick and simple solution:

App needs to updates via GPS use android.hardware.location.gps. If you want updates via the WiFi and cellular networks, you need android.hardware.location.network.

Add below lines to your manifests file based on your location data requirements:

<uses-feature android:name="android.hardware.location" android:required="false" />
<uses-feature android:name="android.hardware.location.gps" android:required="false" />

Hope this helps..



回答4:

From my understanding, it is sufficient to read the documentation for the uses-feature element to understand how applications are filtered in Google Play based upon implicit and explicit uses-feature entries:

Google Play filters the applications that are visible to users, so that users can see and download only those applications that are compatible with their devices. One of the ways it filters applications is by feature compatibility.

To determine an application's feature compatibility with a given user's device, Google Play compares:

Features required by the application — an application declares features in elements in its manifest with... Features available on the device, in hardware or software — a device reports the features it supports as read-only system properties.

...

If a feature is explicitly declared as being required, Google Play adds the feature to the list of required features for the application. It then filters the application from users on devices that do not provide that feature.

If a feature is explicitly declared as not being required, Google Play does not add the feature to the list of required features. For that reason, an explicitly declared non-required feature is never considered when filtering the application. Even if the device does not provide the declared feature, Google Play will still consider the application compatible with the device and will show it to the user, unless other filtering rules apply.


The implicit uses-feature items for location permissions are:

ACCESS_COARSE_LOCATION

  • android.hardware.location
  • android.hardware.location.network (Only when target API level is 20 or lower.)

ACCESS_FINE_LOCATION

  • android.hardware.location
  • android.hardware.location.gps (Only when target API level is 20 or lower.)

The change described in Google's email message is that the implicit uses-feature items for android.hardware.location.gps will not be present in API 21+ with ACCESS_FINE_LOCATION. The analogous situation appears to be true for ACCESS_COARSE_LOCATION and android.hardware.location.network.

Google encourages explicit enumeration of all uses-feature entries, but still provides implicit entries based on permissions. From the following documentation excerpt, I think there is no difference between omitting a uses-feature and declaring it not required, unless there is an implicit uses-feature entry.

If a feature is explicitly declared as not being required, Google Play does not add the feature to the list of required features.


Your application's use case determines what uses-feature entries should be present. Here are some example use cases, with all uses-feature entries being required unless otherwise stated:

  1. Application uses GPS explicitly from LocationManager or application needs GPS' high accuracy. This is the example given in Google's email.

    • ACCESS_FINE_LOCATION
    • android.hardware.location (implicit)
    • android.hardware.location.gps (implicit up to API 20)
  2. Uses Network location explicitly

    • ACCESS_COARSE_LOCATION
    • android.hardware.location (implicit)
    • android.hardware.location.network (implicit up to API 20)
  3. Uses both GPS and Network

    • ACCESS_FINE_LOCATION
    • android.hardware.location (implicit)
    • android.hardware.location.gps (implicit up to API 20)
    • android.hardware.location.network
  4. Uses at least one of GPS and Network. This is my FusedLocationProviderApi case in the original question.

    • ACCESS_FINE_LOCATION/ACCESS_COARSE_LOCATION
    • android.hardware.location (implicit)
  5. Uses location if available, still allows application installation if not available

    • ACCESS_FINE_LOCATION
    • android.hardware.location required=false (override implicit)
    • android.hardware.location.gps required=false (override implicit up to API 20)


回答5:

As per you Questions

Based on the first quotation, I think I do not have to make any changes.

You Don't need to make any changes cause you are using FusedLocation which automatically detect GPS and NetworkProvider as per availability and gives you best estimate location (You need To add ACCESS_FINE_LOCATION permission to get High Accuracy) .So even if you targeting above API version 21 you don't need to change any thing in your app FusedLocation Will work as before.

And As per Second Quotation

You just need to ignore it because you using FusedLocation API And You are not using LocationManager API which you replaced by FusedLocation.So second Quotation is for only apps which using LocationManagar.

NETWORK_PROVIDER and GPS_PROVIDER is Part of LocationManager Not FusedLocation API



回答6:

Yes you need both the permissions if you are using fused provider.

ACCESS_COARSE_LOCATION - To receive location updates from NETWORK_PROVIDER. Adding android.hardware.location.network feature permission is enough.

ACCESS_FINE_LOCATION - To receive location updates from both NETWORK_PROVIDER and GPS_PROVIDER. You should add both android.hardware.location.gps and android.hardware.location.network feature permissions. Applicable for also fused location.