Since version: 1.16
The Location Update Constraint profile allows the map author to write an expression that evaluates whether a new location should be used or not. For example, when location updates are received from a GPS device, the expression may reject location updates with a very poor horizontal accuracy. This profile is used for filtering location updates when working with Geotriggers in ArcGIS Maps SDKs for Native Apps. The script should return a Boolean with true indicating the location meets the constraint criteria or false indicating it does not meet the criteria.
Context
The following products implement this profile:
- ArcGIS Maps SDKs for Native Apps
- ArcGIS Field Maps
Spatial reference
The spatial reference of the map in which the expression executes determines the execution context's spatial reference.
Time zone
The time zone of the map in which the expression executes determines the execution context's default time zone.
Profile variables
| Variable Name | Type | Description |
|---|---|---|
| $locationupdate | Feature | The location update feature (e.g. from GPS) being evaluated for the constraint. |
Note that, when the $locationupdate feature represents a device location, it includes position and metadata of the device - usually obtained from GPS. The feature has a Geometry (usually a point) and a fixed schema with the following properties:
| Property | Type | Description |
|---|---|---|
| course | Number | The course of the location in degrees clockwise, 0 being true North. |
| horizontalaccuracy | Number | The horizontal accuracy of the location in meters. |
| verticalaccuracy | Number | The vertical accuracy of the location in meters. |
| velocity | Number | The velocity of the location in meters per second. |
Function bundles
Return types
Example
The following expression rejects location updates when the horizontal accuracy is over 20 meters:
$locationupdate.horizontalaccuracy <= 20