Flutter图像选择器不会在Android 10中显示

问题描述

我是初学者。我正在检查在flutter中使用image_picker。但是，当我尝试使用Andorid Phone（10）检查image_picker时，它不会显示。我不知道发生了什么，我在AndroidManifest.xml中添加了 android：requestLegacyExternalStorage =“ true” ，

仍然没有变化，我不知道该怎么办？请帮助我

    import 'package:flutter/material.dart';
    import 'package:image_picker/image_picker.dart';
    import 'package:path/path.dart';
    import 'package:path_provider/path_provider.dart';

    void main() {
      runApp(MyApp());
    }

    class MyApp extends StatelessWidget {
      @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',theme: ThemeData(
        primarySwatch: Colors.blue,visualDensity: VisualDensity.adaptivePlatformDensity,),home: MyHomePage(),);
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  File _fileimage;

  final _picker = ImagePicker();

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: <Widget>[
              _fileimage != null
                  ? FileImage(_fileimage)
                  : Text('No image selected'),RaisedButton(
                onPressed: () => _takePicture,child: Text('hi'),)
            ],);
  }

  void _takePicture() async {
    final pickedImage = await _picker.getImage(source: ImageSource.gallery);

    // if (pickedImage == null) {
    //   return;
    // }

    File tmpFile = File(pickedImage.path);

    final Directory directory = await getApplicationDocumentsDirectory();
    final String path = directory.path;

    final String fileName =
        basename(pickedImage.path); // Filename without extension
    final String fileExtension = extension(pickedImage.path); // e.g.

    tmpFile = await tmpFile.copy('$path/$fileName$fileExtension');
    setState(() => _fileimage = tmpFile);
  }
}

解决方法

我发现您的代码有问题。 您在“小部件”中使用的“ FileImage”是必需的。由于“ FileImage”返回“ ImageProvider”，因此应使用“ Image.file（）”而不是“ FileImage”。

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:path/path.dart';
import 'package:path_provider/path_provider.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',theme: ThemeData(
        primarySwatch: Colors.blue,visualDensity: VisualDensity.adaptivePlatformDensity,),home: MyHomePage(),);
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  File _fileimage;

  final _picker = ImagePicker();

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: <Widget>[
              _fileimage != null
                  ? Image.file(_fileimage)
                  : Text('No image selected'),RaisedButton(
                onPressed: () async {
                  _takePicture();
                },child: Text('hi'),)
            ],);
  }

  void _takePicture() async {
    final pickedImage = await _picker.getImage(source: ImageSource.gallery);

    // if (pickedImage == null) {
    //   return;
    // }

    File tmpFile = File(pickedImage.path);

    final Directory directory = await getApplicationDocumentsDirectory();
    final String path = directory.path;

    final String fileName =
        basename(pickedImage.path); // Filename without extension
    final String fileExtension = extension(pickedImage.path); // e.g.

    tmpFile = await tmpFile.copy('$path/$fileName$fileExtension');
    setState(() => _fileimage = tmpFile);
  }
}