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下面我粘贴了来自flutter_map示例的状态标记的代码，我在flutter_map文档中添加了changeMarkerPos方法

https://pub.dev/documentation/flutter_map/latest/flutter_map.plugin_api/Marker-class.html

它说这一点是最终的，所以从某种意义上说，当您创建标记时，不能直接更改 latlng 吗？可能您必须在数组更改后更新 MarkerLayerOptions？当您键入 .point 时，它会立即通知它是最终的？

我想要实现的只是拥有一个初始化的标记数组，然后更改其中一个标记位置而不重绘所有标记，谢谢！

import 'dart:math';

import 'package:flutter/material.dart';
import 'package:flutter_map/flutter_map.dart';
import 'package:latlong2/latlong.dart';

import '../widgets/drawer.dart';

class StatefulMarkersPage extends StatefulWidget {
static const String route = '/stateful_markers';

@override
_StatefulMarkersPageState createState() => _StatefulMarkersPageState();
}

class _StatefulMarkersPageState extends State {
late List _markers;
final Random _random = Random();

@override
void initState() {
super.initState();
_markers = [];
_addMarker('key1');
_addMarker('key2');
_addMarker('key3');
_addMarker('key4');
_addMarker('key5');
_addMarker('key6');
_addMarker('key7');
_addMarker('key8');
_addMarker('key9');
_addMarker('key10');
}

void _addMarker(String key) {
_markers.add(Marker(
width: 40.0,
height: 40.0,
point: LatLng(
_random.nextDouble() * 10 + 48, _random.nextDouble() * 10 - 6),
builder: (ctx) => _ColorMarker(),
key: ValueKey(key)));
}

// THIS DOES NOT WORK
void changeMarkerPos() {
_markers[0].point =
LatLng(_random.nextDouble() * 10 + 48, _random.nextDouble() * 10 - 6);
}

@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('Stateful Markers')),
drawer: buildDrawer(context, StatefulMarkersPage.route),
body: Padding(
padding: EdgeInsets.all(8.0),
child: Column(
children: [
Padding(
padding: EdgeInsets.only(top: 8.0, bottom: 8.0),
child: Text('This is a map that is showing (51.5, -0.9).'),
),
Flexible(
child: FlutterMap(
options: MapOptions(
center: LatLng(51.5, -0.09),
zoom: 5.0,
),
layers: [
TileLayerOptions(
urlTemplate:
'https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png',
subdomains: ['a', 'b', 'c'],
// For example purposes. It is recommended to use
// TileProvider with a caching and retry strategy, like
// NetworkTileProvider or CachedNetworkTileProvider
tileProvider: NonCachingNetworkTileProvider(),
),
MarkerLayerOptions(markers: _markers)
],
),
),
],
),
),
);
}
}

class _ColorMarker extends StatefulWidget {
_ColorMarker({Key? key}) : super(key: key);

@override
_ColorMarkerState createState() => _ColorMarkerState();
}

class _ColorMarkerState extends State<_ColorMarker> {
late final Color color;

@override
void initState() {
super.initState();
color = _ColorGenerator.getColor();
}

@override
Widget build(BuildContext context) {
return Container(color: color);
}
}

class _ColorGenerator {
static List colorOptions = [
Colors.blue,
Colors.red,
Colors.green,
Colors.yellow,
Colors.purple,
Colors.orange,
Colors.indigo,
Colors.amber,
Colors.black,
Colors.white,
Colors.brown,
Colors.pink,
Colors.cyan
];

static final Random _random = Random();

static Color getColor() {
return colorOptions[_random.nextInt(colorOptions.length)];
}
}


  [1]: https://pub.dev/documentation/flutter_map/latest/flutter_map.plugin_api/Marker-class.html
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