Flutter_map: Crash when calling setState on onPositionChanged

[spvalencia]

I want to display the map position (latitude and longitude) when the position changes (onPositionChanged).

When I call setState to do that the app crash.

onPositionChanged: (option, gestures, _) {
setState(() => _mapLocation = option.center);
},

[johnpryan]

can you provide a short example?

[spvalencia]

I fixed adding a little delay.

It occurs when I call setState when map position (center) changes

onPositionChanged: (option, gestures, _) { setState((){}); },

[besedin]

What about using addPostFrameCallback?

For example,

@override
Widget build(BuildContext context) {
  bool _building = true;

  WidgetsBinding.instance.addPostFrameCallback((_) {
    _building = false;
  });

...

onPositionChanged: (MapPosition position, bool hasGesture, bool isUserGesture) {
  if (!_building)
    setState(() { ... }
}

[johnpryan]

It seems like the onPositionChanged callback is getting invoked during a build()

[nicowernli]

Same happens to me. The onPositionChanged is getting invoked with the initial map positioning I guess.

[alves-luis]

What about using addPostFrameCallback?

For example,

@override
Widget build(BuildContext context) {
  bool _building = true;

  WidgetsBinding.instance.addPostFrameCallback((_) {
    _building = false;
  });

...

onPositionChanged: (MapPosition position, bool hasGesture, bool isUserGesture) {
  if (!_building)
    setState(() { ... }
}

This solved the issue for me.