Exposing GoogleMap.OnCameraMoveStartedListener "reason"

[Bmahecha123]

I hooked up fusedLocationClient to cameraPositionState to keep current location regularly updated. I have some logic related to the isMoving flag. However I noticed that this flag is constantly toggling.

Could we expose OnCameraMoveStartedListener so I can check the reason as a flag instead? https://developers.google.com/android/reference/com/google/android/gms/maps/GoogleMap.OnCameraMoveStartedListener

This is currently not exposed. Thanks <3!

[jpoehnelt]

@Bmahecha123 Thank you for opening this issue. 🙏
Please check out these other resources that might be applicable:

• Support Console - If you have a support contract.
• Discord - chat with other developers
• StackOverflow - use the google-maps tag
• Google Maps Platform issue trackers

This is an automated message, feel free to ignore.

[arriolac]

Is what you're trying to do not doable with the current isMoving flag? Not sure what you're trying to achieve but you should be able to perform a computation using LaunchedEffect keyed on isMoving. If you can share more of your use case that would be helpful @Bmahecha123

[barbeau]

@Bmahecha123 can elaborate, but I believe the use case here is to allow the developer to know when the user is interacting with the map so the app doesn't introduce conflicting camera movements.

A use case I've hit in the past is to show real-time user location on the map and on each location update move the map to center on the location. But if the user pans the map, you want to stop moving the map based on the location updates otherwise the user ends up fighting the location updates for control.

GoogleMap.OnCameraMoveStartedListener introduced a reason flag in onCameraMoveStarted() that allows the developer to know why the map moved:

abstract void	onCameraMoveStarted(int reason)	Called when the camera starts moving after it has been idle or when the reason for camera motion has changed.

int	REASON_API_ANIMATION	Non-gesture animation initiated in response to user actions.
int	REASON_DEVELOPER_ANIMATION	Developer initiated animation.
int	REASON_GESTURE	Camera motion initiated in response to user gestures on the map.

But from what I can see this flag isn't exposed in maps-compose.

[arriolac]

Thanks for clarifying @barbeau . It looks like the library is swallowing the reason flag and should be exposed as a property to CameraPositionState. See: https://github.com/googlemaps/android-maps-compose/blob/main/maps-compose/src/main/java/com/google/maps/android/compose/MapUpdater.kt#L72

[Bmahecha123]

Thank you for the clarification @barbeau !

Relying on isMoving is not trustworthy since this flag can switch between true/false many times depending on location updates (fractions of a latitude/longitude even if phone is stationary). Relying on reason is more reliable since I can filter based on user based movement or camera updates by the native client.

[barbeau]

Thanks @arriolac, that makes sense. I can try tackling this. My plan would be to finish the work in PR #94 that adds more examples in the app, and then add this feature along with a sample implementation in the demo app.

[barbeau]

I'm actually realizing that this issue is a duplicate of #49, so I'm going to close this in favor of that because it's older. So please upvote #49 if you're following this issue and haven't seen #49 yet.