嘿，我正在尝试向我的 flutter 应用程序添加权限处理程序，但是当我单击按钮时，它在设备上完全没有任何响应（它没有显示请求权限的对话框）。我尝试制作另一个项目并在那里做同样的事情，在那里效果很好。
Restarted application in 1,738ms.
E/flutter (20650): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: PlatformException(error, java.lang.IllegalStateException: Trying to create a platform view of unregistered type: com.pichillilorenzo/flutter_inappwebview
E/flutter (20650): at io.flutter.plugin.platform.PlatformViewsController.createPlatformView(PlatformViewsController.java:513)
E/flutter (20650): at io.flutter.plugin.platform.PlatformViewsController$1.createForPlatformViewLayer(PlatformViewsController.java:169)
E/flutter (20650): at io.flutter.embedding.engine.systemchannels.PlatformViewsChannel$1.create(PlatformViewsChannel.java:105)
E/flutter (20650): at io.flutter.embedding.engine.systemchannels.PlatformViewsChannel$1.onMethodCall(PlatformViewsChannel.java:55)
E/flutter (20650): at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:267)
E/flutter (20650): at io.flutter.embedding.engine.dart.DartMessenger.invokeHandler(DartMessenger.java:292)
E/flutter (20650): at io.flutter.embedding.engine.dart.DartMessenger.lambda$dispatchMessageToQueue$0$io-flutter-embedding-engine-dart-DartMessenger(DartMessenger.java:319)
E/flutter (20650): at io.flutter.embedding.engine.dart.DartMessenger$$ExternalSyntheticLambda0.run(Unknown Source:12)
E/flutter (20650): at android.os.Handler.handleCallback(Handler.java:958)
E/flutter (20650): at android.os.Handler.dispatchMessage(Handler.java:99)
E/flutter (20650): at android.os.Looper.loopOnce(Looper.java:224)
E/flutter (20650): at android.os.Looper.loop(Looper.java:318)
E/flutter (20650): at android.app.ActivityThread.main(ActivityThread.java:8727)
E/flutter (20650): at java.lang.reflect.Method.invoke(Native Method)
E/flutter (20650): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:561)
E/flutter (20650): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1013)
E/flutter (20650): , null, null)
E/flutter (20650): #0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:651:7)
E/flutter (20650): #1 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:334:18)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650): #2 ExpensiveAndroidViewController._sendCreateMessage (package:flutter/src/services/platform_views.dart:1115:5)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650): #3 AndroidViewController.create (package:flutter/src/services/platform_views.dart:838:5)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650):
W/WindowOnBackDispatcher(20650): OnBackInvokedCallback is not enabled for the application.
W/WindowOnBackDispatcher(20650): Set 'android:enableOnBackInvokedCallback="true"' in the application manifest.
E/flutter (20650): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: MissingPluginException(No implementation found for method requestPermissions on channel flutter.baseflow.com/permissions/methods)
E/flutter (20650): #0 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:332:7)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650): #1 MethodChannelPermissionHandler.requestPermissions (package:permission_handler_platform_interface/src/method_channel/method_channel_permission_handler.dart:80:9)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650): #2 PermissionActions.request (package:permission_handler/permission_handler.dart:109:10)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650): #3 _ShopsState.build.<anonymous closure> (package:pos/screens/Shops/shops.dart:83:23)
E/flutter (20650): <asynchronous suspension>
E/flutter (20650):
这是我在其中应用权限处理程序的文件
import 'package:flutter/material.dart';
import 'package:pos/Screens/OtherPages/new_shop_form.dart';
import 'package:pos/Screens/OtherPages/shop_management_screen.dart';
import 'package:pos/constants.dart';
import 'package:pos/labels.dart';
import 'package:pos/CommonWidgets/button.dart';
import 'package:pos/screens/LoginSignupScreens/SignUp/page_view.dart';
import 'package:pos/screens/LoginSignupScreens/login.dart';
import 'package:permission_handler/permission_handler.dart';
class Shops extends StatefulWidget {
const Shops({super.key});
@override
_ShopsState createState() => _ShopsState();
}
class _ShopsState extends State<Shops> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
actions: [
IconButton(
icon: const Icon(Icons.volume_up),
onPressed: () {},
),
],
),
body: Stack(
children: [
Container(
decoration: const BoxDecoration(
image: DecorationImage(
image: AssetImage("assets/backgrounds/bg_image3.png"),
fit: BoxFit.cover,
),
),
),
Column(
crossAxisAlignment: CrossAxisAlignment.center,
children: [
Container(),
const ImageIcon(
AssetImage('assets/images/shop.png'),
size: 130,
color: kTextColor,
),
Text(
Labels.shop(),
style: const TextStyle(color: kTextColor, fontSize: 24),
),
const SizedBox(height: 40),
LanguageButton(
text: Labels.addShop(),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const Newformshop(),
),
);
},
borderColor: kBorderColor1,
textColor: kTextColor,
width: MediaQuery.of(context).size.width * 0.8,
height: 70,
borderWidth: 3,
borderRadius: 100,
textSize: 26,
),
const SizedBox(height: 20),
LanguageButton(
text: Labels.shop(),
onTap: () async {
// Navigator.push(
// context,
// MaterialPageRoute(
// builder: (context) => const ShopManagementScreen(),
// ),
// );
PermissionStatus cameraStatus =
await Permission.camera.request();
print('Camera permission status: $cameraStatus');
if (cameraStatus.isGranted) {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const ShopManagementScreen(),
),
);
} else if (cameraStatus.isDenied) {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(content: Text("Camera permission denied")),
);
} else if (cameraStatus.isPermanentlyDenied) {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(
content:
Text("Camera permission permanently denied")),
);
await openAppSettings(); // Open app settings
}
},
borderColor: kBorderColor1,
textColor: kTextColor,
width: MediaQuery.of(context).size.width * 0.8,
height: 70,
borderWidth: 3,
borderRadius: 100,
textSize: 26,
),
const SizedBox(height: 10),
LanguageButton(
text: 'LOL1',
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const Login(),
),
);
},
borderColor: kBorderColor1,
textColor: kTextColor,
width: MediaQuery.of(context).size.width * 0.8,
height: 70,
borderWidth: 3,
borderRadius: 100,
textSize: 26,
),
LanguageButton(
text: 'LOL2',
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => MultiStepForm(),
),
);
},
borderColor: kBorderColor1,
textColor: kTextColor,
width: MediaQuery.of(context).size.width * 0.8,
height: 70,
borderWidth: 3,
borderRadius: 100,
textSize: 26,
),
],
),
],
),
);
}
}
这是Android.xml文件
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.pos">
<uses-permission android:name="android.permission.CAMERA" />
<application
android:label="pos"
android:name="${applicationName}"
android:icon="@mipmap/ic_launcher">
<activity
android:name=".MainActivity"
android:exported="true"
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">
<meta-data
android:name="io.flutter.embedding.android.NormalTheme"
android:resource="@style/NormalTheme" />
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<meta-data
android:name="flutterEmbedding"
android:value="2" />
</application>
<queries>
<intent>
<action android:name="android.intent.action.PROCESS_TEXT" />
<data android:mimeType="text/plain" />
</intent>
</queries>
</manifest>
依赖关系：
dependencies:
flutter:
sdk: flutter
permission_handler: ^11.3.1
# flutter_inappwebview: ^6.0.0
youtube_player_flutter: ^9.0.1
simple_barcode_scanner: ^0.0.8
flutter_barcode_scanner: ^2.0.0
mobile_scanner: ^5.0.1
camera: ^0.10.5+9
flutter_svg: ^2.0.10+1
Flutter doctor:
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.19.6, on Microsoft Windows [Version 10.0.22000.2538], locale en-US)
[√] Windows Version (Installed version of Windows is version 10 or higher)
[√] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
[√] Chrome - develop for the web
[√] Visual Studio - develop Windows apps (Visual Studio Community 2019 16.11.34)
[√] Android Studio (version 2023.2)
[√] VS Code (version 1.89.1)
[√] Connected device (4 available)
[√] Network resources
我尝试制作另一个项目并在那里做同样的事情，效果很好。我还尝试运行 flutter clean 并再次构建它但不起作用:(
您使用的权限处理程序错误，这就是您获取权限当前状态的方式
PermissionStatus cameraStatus =
await Permission.camera.status;
然后检查权限是否被授予，如果权限没有被永久拒绝，那么你可以使用请求
status = await Permission.camera.request();
这是我的代码中的示例用法
var status = await Permission.camera.status;
if (status.isGranted) {
//do something
}
if (status.isPermanentlyDenied) {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(
content: Text('Camera permission permanently denied'),
),
);
} else {
status = await Permission.camera.request();
if (status.isGranted) {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(
content: Text('Camera permission granted'),
),
);
} else {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(
content: Text('Camera permission denied'),
),
);
}
}