Android Question geofence with google play services

[jchal]

hellow guys
now it is time to learn how to make a geofence with google play services???
whare do i start, i know how google play serivices are working at the monet...........
how do we do the geofence control,the idea is to mark an area in google maps and that the marker is not alowed to enter or the marker is not alowed to live ....
how do we do it?

 

[JordiCP]

I suppose you meant "...the marker is not alowed to leave..."

if not, I wouldn't dare to enter into that area

 

[jchal]

Yes the marker,
Do you have some idea on were to start?

 

[JordiCP]

I would start setting up a working example using @warwound 's FusedLocationProvider , B4A GoogleMaps and GoogleMapsExtras. These libraries use google play services
Then, by knowing your position and your distance to the center of a circular area, you can know if your marker is inside or outside.
Once you feel comfortable with this part, I would start with non-circular geofences, by replacing the "distance" criteria (for circular areas) with a more advanced algorithm (for polygonal areas)

 

[jchal]

do you know the algorithm for polygonal areas?

 

[JordiCP]

There are some posts in this forum regarding this.

Here one of @klaus

https://www.b4x.com/android/forum/threads/geo-zone-determination-point-in-polygon.53929/#post-339569