Android Tutorial GPS / GNSS tutorial

The GNSS library replaces the old GPS library. The GNSS library is available here: https://www.b4x.com/android/forum/threads/gnss-library-an-updated-gps-library.109110/#content

Using it is quite simple:
1. Checking whether location services are available. If not take the user to the settings.
2. Request permission.

If the purpose is to get the user location then the FusedLocationProvider might be a better option: https://www.b4x.com/android/forum/threads/fusedlocationprovider-resolution-dialog.111652/#content

 

[Rusty]

in the unfiltered logs I discovered:

[VERIFY] PACKAGE_VERIFIED:
PackageVerificationState{
verifier packages=com.android.vending(10034),
intent=Intent { act=android.intent.action.PACKAGE_NEEDS_VERIFICATION dat=file:///storage/emulated/0/Android/data/anywheresoftware.b4a.b4abridge/files/temp1.apk typ=application/vnd.android.package-archive flg=0x10000001 cmp=com.android.vending/com.google.android.vending.verifier.PackageVerificationReceiver VirtualScreenParam=Params{mDisplayId=-1, null, mFlags=0x00000000)} (has extras) }
others=95, false, false, false, false, false
}
[VERIFY] packageVerificationCompletion: completed id=95
[VERIFY] setVerifierResponse {verificationID=95, uid=10034, code=1
[VERIFY] broadcastPackageVerified(95, VERIFICATION_ALLOW, file:///storage/emulated/0/Android/data/anywheresoftware.b4a.b4abridge/files/temp1.apk)
copyApk
Killing 6454:com.amazon.mShop.android/u0a84 (adj 15): empty for 1805s
remove MCS_UNBIND and Posting MCS_UNBIND
Make sure sdcard is mounted.

The app was set to #CanInstallToExternalStorage: True and my phone does not have an SD card installed.
I changed it to #CanInstallToExternalStorage: False and it now installs.
Thanks Erel, I should have looked at the un-filtered logs before.
Regards,
Rusty

 

[Almora]

is it possible to measure altitude?

 

[Erel]

Yes. The Location object includes the altitude value.

 

[Almora]

Yes. The Location object includes the altitude value.

how can you show just the red zone..

 

[Erel]

https://www.b4x.com/search?query=NumberFormat

 

[Peekay]

Erel,
In the above code you refer to a routine rp in module Starter, but I do not find that in your example code.

 

[Erel]

rp is an instance of RuntimePermissions. It is declared in Process_Globals of the Starter service.

 

[kris A]

How accurate location GPS it show me on map 30m from where I was
is it possible to take this down to 2m - 10m?

My device : Xiaomi Redmi Note 2
Android version : 5

Thanks

 

[Erel]

Please start a new thread for this question.

 

[kris A]

Please start a new thread for this question.

Thanks @Erel , my threat for question in : https://www.b4x.com/android/forum/threads/how-to-take-down-accurate-gps-location.74811/

 

[Husain Ragib]

Erel, I am abeginner in b4a.
I downloaded the GPS example and tried to see the output via. B4A bridge connected with my android phone.
But I could get any information against the labels.
GPS is enabled in my phone. Can you please help me

 

[DonManfred]

1. ALWAYS start a new thread in the questions forum for any question you have.
2. Did you tried it outdoors? Indoors the gps signal is weak/not available

 

[svein berg]

Hi.
I'm new to B4A, but so far I like it.
Have a problem with the GPS.

I would like the "GPS1_LocationChanged (Location1 As Location)" to fire every 2 seconds or if Location have changed more than one meter.
So I put;
gps1.Start(2000,1 )

But then the "changed event" keep firing like mad without the location changing at all. (Phone is still on my table)

In the "Activity_Create" - FirstTime I have;
If gps1.IsInitialized Then gps1.Stop
as I dont want it to fire before I have initiated a logon procedure, but its firing..

I'm using B4A v 6.0 and have a Samsung with Android 6.0

Any help??

 

[Erel]

1. GPS accuracy error can be more than 10 meters.
2. These values are only a hint to the system about your requirements. You need to add your own code to filter out unwanted events.

 

[svein berg]

Thanks Erel..
GPS Error is not part of this as I display the Lat,Lon in each LocationChanged, and the error is much less than 1 meter.

Isnt it possible to stop the Activity from listening to the GPS?

 

[Erel]

You can call GPS.Stop to stop listening.

 

[gregmatthews]

All the examples get a lat, lon pair in the locationchanged event. Does this mean the event needs to fire at least once to get a location ? What happens if you start the app and are perfectly still? Can you still get a location?

Thanks

 

[Erel]

It fires all the time. Even if the location hasn't changed.

 

[gregmatthews]

Hi Erel,
Thanks - my issue must be somewhere else then!
To clarify:
The locationChanged event will fire either after a certain number of milliseconds OR after a change in position, the thresholds for each set via the GPS.Start(x,y) function. So if that is GPS.Start(0,0) then it will rapid fire. If GPS.Start(5000,50) if will fire every 5s or if the position changes by 50m, but not more frequently than that?

Greg

 

[Erel]

but not more frequently than that?

This is just a hint to the system. It can (and will) fire more frequent.