我正在构建一个应用程序，该应用程序使用flutter包中提供的Geo Locator包显示当前位置。我使用的是最新版本7.6.1。有一个按钮叫做"获取位置"，点击它必须打印位置。
一旦我点击获取位置按钮，我得到这个错误Error_Image
这是我的Pubspec。yaml文件
name: clima
description: A new Flutter application.
version: 1.0.0+1
environment:
sdk: ">=2.1.0 <3.0.0"
dependencies:
flutter:
sdk: flutter
cupertino_icons: ^0.1.2
geolocator: ^7.6.1
dev_dependencies:
flutter_test:
sdk: flutter
flutter:
uses-material-design: true
assets:
- images/city_background.jpg
- images/location_background.jpg
fonts:
- family: Spartan MB
fonts:
- asset: fonts/SpartanMB-Black.otf
weight: 900
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.clima">
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<!-- io.flutter.app.FlutterApplication is an android.app.Application that
calls FlutterMain.startInitialization(this); in its onCreate method.
In most cases you can leave this as-is, but you if you want to provide
additional functionality it is fine to subclass or reimplement
FlutterApplication and put your custom class here. -->
<application
android:label="clima"
android:icon="@mipmap/ic_launcher">
<activity
android:name=".MainActivity"
android:launchMode="singleTop"
android:theme="@style/LaunchTheme"
android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
android:hardwareAccelerated="true"
android:windowSoftInputMode="adjustResize">
<!-- Specifies an Android theme to apply to this Activity as soon as
the Android process has started. This theme is visible to the user
while the Flutter UI initializes. After that, this theme continues
to determine the Window background behind the Flutter UI. -->
<meta-data
android:name="io.flutter.embedding.android.NormalTheme"
android:resource="@style/NormalTheme"
/>
<!-- Displays an Android View that continues showing the launch screen
Drawable until Flutter paints its first frame, then this splash
screen fades out. A splash screen is useful to avoid any visual
gap between the end of Android's launch screen and the painting of
Flutter's first frame. -->
<meta-data
android:name="io.flutter.embedding.android.SplashScreenDrawable"
android:resource="@drawable/launch_background"
/>
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<!-- Don't delete the meta-data below.
This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
<meta-data
android:name="flutterEmbedding"
android:value="2" />
</application>
</manifest>
我的信息。ios的列表文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>NSLocationWhenInUseUsageDescription</key>
<string>This app needs access to location when open.</string>
<key>CFBundleDevelopmentRegion</key>
<string>$(DEVELOPMENT_LANGUAGE)</string>
<key>CFBundleExecutable</key>
<string>$(EXECUTABLE_NAME)</string>
<key>CFBundleIdentifier</key>
<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
<key>CFBundleInfoDictionaryVersion</key>
<string>6.0</string>
<key>CFBundleName</key>
<string>clima</string>
<key>CFBundlePackageType</key>
<string>APPL</string>
<key>CFBundleShortVersionString</key>
<string>$(FLUTTER_BUILD_NAME)</string>
<key>CFBundleSignature</key>
<string>????</string>
<key>CFBundleVersion</key>
<string>$(FLUTTER_BUILD_NUMBER)</string>
<key>LSRequiresIPhoneOS</key>
<true/>
<key>UILaunchStoryboardName</key>
<string>LaunchScreen</string>
<key>UIMainStoryboardFile</key>
<string>Main</string>
<key>UISupportedInterfaceOrientations</key>
<array>
<string>UIInterfaceOrientationPortrait</string>
<string>UIInterfaceOrientationLandscapeLeft</string>
<string>UIInterfaceOrientationLandscapeRight</string>
</array>
<key>UISupportedInterfaceOrientations~ipad</key>
<array>
<string>UIInterfaceOrientationPortrait</string>
<string>UIInterfaceOrientationPortraitUpsideDown</string>
<string>UIInterfaceOrientationLandscapeLeft</string>
<string>UIInterfaceOrientationLandscapeRight</string>
</array>
<key>UIViewControllerBasedStatusBarAppearance</key>
<false/>
</dict>
</plist>
我的代码
Main.dart
进口"包:颤振/material.dart";导入的包:此种/屏幕/loading_screen.dart’;
void main() =>runApp (MyApp ());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.dark(),
home: LoadingScreen(),
);
}
}
在屏幕目录下3文件
city_screen.dart、loading_screen.dart location_screen.dart
city_screen.dart
import 'package:flutter/material.dart';
import 'package:clima/utilities/constants1.dart';
class CityScreen extends StatefulWidget {
@override
_CityScreenState createState() => _CityScreenState();
}
class _CityScreenState extends State<CityScreen> {
@override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage('images/city_background.jpg'),
fit: BoxFit.cover,
),
),
constraints: BoxConstraints.expand(),
child: SafeArea(
child: Column(
children: <Widget>[
Align(
alignment: Alignment.topLeft,
child: FlatButton(
onPressed: () {},
child: Icon(
Icons.arrow_back_ios,
size: 50.0,
),
),
),
Container(
padding: EdgeInsets.all(20.0),
child: null,
),
FlatButton(
onPressed: () {},
child: Text(
'Get Weather',
style: kButtonTextStyle,
),
),
],
),
),
),
);
}
}
loading_screen.dart
import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';
class LoadingScreen extends StatefulWidget {
@override
_LoadingScreenState createState() => _LoadingScreenState();
}
class _LoadingScreenState extends State<LoadingScreen> {
Future<void> getLocation()
async {
LocationPermission permission = await Geolocator.requestPermission();
Position position = await Geolocator.getCurrentPosition(desiredAccuracy: LocationAccuracy.low); //high is battery consuming
print(position);
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: RaisedButton(
onPressed: () {
getLocation();//Get the current location
},
child: Text('Get Location'),
),
),
);
}
}
Location_screen.dart
import 'package:geolocator/geolocator.dart';
import 'package:flutter/material.dart';
import 'package:clima/utilities/constants1.dart';
class LocationScreen extends StatefulWidget {
@override
_LocationScreenState createState() => _LocationScreenState();
}
class _LocationScreenState extends State<LocationScreen> {
@override
Future<void> getLocation()
async {
LocationPermission permission = await Geolocator.requestPermission();
Position position = await Geolocator.getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
print(position);
}
Widget build(BuildContext context) {
return Scaffold(
body: Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage('images/location_background.jpg'),
fit: BoxFit.cover,
colorFilter: ColorFilter.mode(
Colors.white.withOpacity(0.8), BlendMode.dstATop),
),
),
constraints: BoxConstraints.expand(),
child: SafeArea(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
FlatButton(
onPressed: () {},
child: Icon(
Icons.near_me,
size: 50.0,
),
),
FlatButton(
onPressed: () {},
child: Icon(
Icons.location_city,
size: 50.0,
),
),
],
),
Padding(
padding: EdgeInsets.only(left: 15.0),
child: Row(
children: <Widget>[
Text(
'32°',
style: kTempTextStyle,
),
Text(
'☀️',
style: kConditionTextStyle,
),
],
),
),
Padding(
padding: EdgeInsets.only(right: 15.0),
child: Text(
"It's 🍦 time in San Francisco!",
textAlign: TextAlign.right,
style: kMessageTextStyle,
),
),
],
),
),
),
);
}
}
在utilities目录下有一个文件constants1.dart
constants1.dart
import 'package:flutter/material.dart';
const kTempTextStyle = TextStyle(
fontFamily: 'Spartan MB',
fontSize: 100.0,
);
const kMessageTextStyle = TextStyle(
fontFamily: 'Spartan MB',
fontSize: 60.0,
);
const kButtonTextStyle = TextStyle(
fontSize: 30.0,
fontFamily: 'Spartan MB',
);
const kConditionTextStyle = TextStyle(
fontSize: 100.0,
);
services目录下有weather.dart
weather.dart
class WeatherModel {
String getWeatherIcon(int condition) {
if (condition < 300) {
return '🌩';
} else if (condition < 400) {
return '🌧';
} else if (condition < 600) {
return '☔️';
} else if (condition < 700) {
return '☃️';
} else if (condition < 800) {
return '🌫';
} else if (condition == 800) {
return '☀️';
} else if (condition <= 804) {
return '☁️';
} else {
return '🤷';
}
}
String getMessage(int temp) {
if (temp > 25) {
return 'It's 🍦 time';
} else if (temp > 20) {
return 'Time for shorts and 👕';
} else if (temp < 10) {
return 'You'll need 🧣 and 🧤';
} else {
return 'Bring a 🧥 just in case';
}
}
}
在你的getLocation方法中，你没有检查权限…你请求用户许可，但你不检查他们。
首先检查permission，看看它是什么，如果它被授予，然后执行其余的逻辑。
如果问题不在这里，请发布下一个日志，以便我们找出问题所在