Flutter 如何在地图上用颜色标出不同的位置?
让我告诉你我的动机是什么。我正在制作一个应用程序,其中受新冠病毒高度影响的位置以红色、橙色和绿色显示。它们实际上是圆形的容器,有这三种颜色。 但是,我没有得到输出,因为我已经创建了这个。 请参阅代码:-Flutter 如何在地图上用颜色标出不同的位置?,flutter,dart,flutter-layout,mapbox,flutter-test,Flutter,Dart,Flutter Layout,Mapbox,Flutter Test,让我告诉你我的动机是什么。我正在制作一个应用程序,其中受新冠病毒高度影响的位置以红色、橙色和绿色显示。它们实际上是圆形的容器,有这三种颜色。 但是,我没有得到输出,因为我已经创建了这个。 请参阅代码:- import 'package:flutter/material.dart'; import 'package:latlong/latlong.dart'; import 'package:flutter_map/flutter_map.dart'; import 'package:http/h
import 'package:flutter/material.dart';
import 'package:latlong/latlong.dart';
import 'package:flutter_map/flutter_map.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
class MapIntegration extends StatefulWidget {
@override
_MapIntegrationState createState() => _MapIntegrationState();
}
class _MapIntegrationState extends State<MapIntegration> {
List redZoneData = new List();
List orangeZoneData = new List();
List greenZoneData = new List();
Map overallData = {
"Gujarat": LatLng(20.5937, 78.9629),
"Dehi": LatLng(20.5937, 78.9629)
};
int n = 2;
Map mapData;
var totalConfirmed;
var dataCalc;
var death;
var stateCode;
mapDataValue() async {
final url = 'https://api.rootnet.in/covid19-in/stats/latest';
final response = await http.get(url);
mapData = json.decode(response.body);
if (response.statusCode == 200) {
setState(() {
for (int index = 0;
index < mapData['data']['regional'].length;
index++) {
totalConfirmed = mapData['data']['regional'][index]['totalConfirmed'];
death = mapData['data']['regional'][index]['deaths'];
dataCalc = double.parse((totalConfirmed / death).toStringAsFixed(2));
stateCode = mapData['data']['regional'][index]['loc'];
if (dataCalc <= 40.00) {
redZoneData.add(stateCode);
} else {
// print(stateCode);
if (dataCalc > 40.00 && dataCalc <= 50.00) {
orangeZoneData.add(stateCode);
} else {
greenZoneData.add(stateCode);
}
}
}
print(redZoneData);
print(orangeZoneData);
print(greenZoneData);
});
} else {
throw Exception('loading failed...');
}
}
Widget dataEvaluation() {
var marker;
for (int index = 0; index < mapData['data']['regional'].length; index++) {
if (redZoneData.contains(mapData['data']['regional'][index]['loc'])) {
marker = new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(20.5937, 78.9629),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.red,
),
),
);
} else if (orangeZoneData
.contains(mapData['data']['regional'][index]['loc'])) {
marker = new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(20.5937, 78.9629),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.orange,
),
),
);
} else if (greenZoneData
.contains(mapData['data']['regional'][index]['loc'])) {
marker = new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(20.5937, 78.9629),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.green,
),
),
);
}
}
return marker;
}
@override
void initState() {
mapDataValue();
super.initState();
}
@override
Widget build(BuildContext context) {
return Container(
height: MediaQuery.of(context).size.height / 1.3,
child: Column(
children: [
Container(
decoration: new BoxDecoration(
borderRadius: new BorderRadius.circular(30.0),
),
height: MediaQuery.of(context).size.height / 1.5,
alignment: Alignment.centerRight,
child: FlutterMap(
options: new MapOptions(
center: LatLng(22.5937, 78.9629),
zoom: 4.3,
),
layers: [
new TileLayerOptions(
urlTemplate:
'https://api.mapbox.com/styles/v1/shivam7007/ckevbwl2u6ty11an4bfbicex7/tiles/256/{z}/{x}/{y}@2x?access_token=pk.eyJ1Ijoic2hpdmFtNzAwNyIsImEiOiJja2VsMzRrcmcweW9vMnlwaXNiMzFrYjV2In0.CVRHP4CkMz_5UybuZ3CaIA',
additionalOptions: {
'acessToken':
'pk.eyJ1Ijoic2hpdmFtNzAwNyIsImEiOiJja2V0bXl4OXIxbmRrMnRvZWdkaWM5a29zIn0.doc-sYseA4b-Z7ylnp0Ttg',
'id': 'mapbox.mapbox-streets-v8',
},
),
new MarkerLayerOptions(
markers: [
dataEvaluation(),
],
),
],
),
),
Text('$dataCalc'),
],
),
);
}
}
导入“包装:颤振/材料.省道”;
导入“包:latlong/latlong.dart”;
导入“包:颤振图/颤振图.dart”;
将“package:http/http.dart”导入为http;
导入“dart:convert”;
类MapIntegration扩展StatefulWidget{
@凌驾
_MapIntegrationState createState()=>\u MapIntegrationState();
}
类_MapIntegrationState扩展状态{
List redZoneData=新列表();
List orangeZoneData=新列表();
List greenZoneData=新列表();
地图总体数据={
“古吉拉特邦”:拉丁语(20.5937,78.9629),
“德希”:拉丁语(20.5937,78.9629)
};
int n=2;
地图数据;
已确认的风险价值;
var数据计算;
var死亡;
var状态码;
mapDataValue()异步{
最终url=https://api.rootnet.in/covid19-in/stats/latest';
最终响应=等待http.get(url);
mapData=json.decode(response.body);
如果(response.statusCode==200){
设置状态(){
对于(int指数=0;
索引新容器(
身高:10,
宽度:10,
装饰:新盒子装饰(
形状:BoxShape.circle,
颜色:颜色。橙色,
),
),
);
}else if(绿带数据)
.contains(地图数据['data']['regional'][索引]['loc'])){
标记=新标记(
宽度:80.0,
身高:80.0,
要点:新车床(20.5937,78.9629),
建造商:(ctx)=>新容器(
身高:10,
宽度:10,
装饰:新盒子装饰(
形状:BoxShape.circle,
颜色:颜色。绿色,
),
),
);
}
}
返回标记;
}
@凌驾
void initState(){
mapDataValue();
super.initState();
}
@凌驾
小部件构建(构建上下文){
返回容器(
高度:MediaQuery.of(context).size.height/1.3,
子:列(
儿童:[
容器(
装饰:新盒子装饰(
边界半径:新边界半径。圆形(30.0),
),
高度:MediaQuery.of(context).size.height/1.5,
对齐:alignment.centerRight,
孩子:地图(
选项:新地图选项(
中心:拉特林(22.5937,78.9629),
缩放:4.3,
),
图层:[
新TileLayerOptions(
URL模板:
'https://api.mapbox.com/styles/v1/shivam7007/ckevbwl2u6ty11an4bfbicex7/tiles/256/{z} /{x}/{y}@2x?访问令牌=pk.eyj1ijoic2hpdmftnzawnyisimeioiijja2vsmzrrcmcwew9vmnlwaxnimzfryjv2in0.CVRHP4CkMz_5UybuZ3CaIA',
其他选项:{
“acessToken”:
“主键EYJ1IJOIC2HPDMFTNZHANGYISMEIOIJJA2V0BXL4OxiXBMRmnrVZWDKAWM5A29ZIN0.doc-sYseA4b-Z7ylnp0Ttg”,
“id”:“mapbox.mapbox-streets-v8”,
},
),
新MarkerLayerProptions(
标记:[
dataEvaluation(),
],
),
],
),
),
文本(“$dataCalc”),
],
),
);
}
}
并在MarkerLayerOption小部件中调用dataEvaluation()会引发一个名为“元素类型'widget'无法分配给列表类型'Marker'的错误”。
实际上,我已经创建了一个调用dataEvaluation()的函数,该函数将计算状态是否存在于红色、橙色或绿色区域中,并根据该状态返回基于红色、橙色或绿色的容器,该容器将作为地图上的一个点工作。
请解决这个问题,如果您在理解问题时发现任何困难,请告诉我。但是请解决这个问题。我什么也找不到。
API is=我发现了这一点。这很容易,因为Flatter为您提供了在小部件中编写单行代码的功能,所以您可以轻松地完成同样的操作
for (var index in mapDataFinal)
if (redZoneData.contains(index))
new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(26.8467, 80.9462),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.red,
),
),
)
不需要把花括号放在那里。
完整代码如下:
new MarkerLayerOptions(markers: [
for (var index in mapDataFinal)
if (redZoneData.contains(index))
new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(26.8467, 80.9462),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.red,
),
),
)
else if (orangeZoneData.contains(index))
new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(10.8505, 76.2711),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.orange,
),
),
)
else if (greenZoneData.contains(index))
new Marker(
width: 80.0,
height: 80.0,
point: new LatLng(22.2587, 71.1924),
builder: (ctx) => new Container(
height: 10,
width: 10,
decoration: new BoxDecoration(
shape: BoxShape.circle,
color: Colors.green,
),
),
)
]),