如何使用 Flutter 应用程序从文件管理器打开（音频）文件

Question

当用户尝试从他/她的文件管理器打开音频文件时，我想在以下“在哪个应用程序中打开此文件”弹出窗口中向他/她展示我的应用程序。在他从弹出窗口中选择我的应用程序后，我想将文件路径传递给状态变量（currentSong）。

我已经设法将以下 IntentFilter 添加到我的 AndroidManifest.xml 中。这应该会在弹出窗口中正确地向用户显示我的应用：

<intent-filter>
    <action android:name="android.intent.action.VIEW"/>
    <category android:name="android.intent.category.DEFAULT"/>
    <category android:name="android.intent.category.BROWSABLE"/>
    <data android:scheme="http" />
    <data android:scheme="content" />
    <data android:scheme="file" />
    <data android:mimeType="audio/*" />
    <data android:mimeType="application/ogg" />
    <data android:mimeType="application/x-ogg" />
    <data android:mimeType="application/itunes" />
</intent-filter>

但现在我一无所知。 Flutter中如何获取文件路径并保存到状态变量currentSong中？

Answer 1

您需要使用ChannelPlatform 来执行此操作：

1.安卓端：

   Handle onCreate + onNewIntent to get bundle data from File Viewer App that share audio file's path

2。 Flutter 方面：

  get audio file's path and do something...

演示：

示例：

安卓

import android.content.Intent
import android.os.Bundle
import androidx.annotation.NonNull
import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugin.common.MethodChannel
import io.flutter.plugins.GeneratedPluginRegistrant

class MainActivity : FlutterActivity() {
    private val CHANNEL = "tinyappsteam.flutter.dev/open_file"

    var openPath: String? = null
    override fun configureFlutterEngine(@NonNull flutterEngine: FlutterEngine) {
        GeneratedPluginRegistrant.registerWith(flutterEngine)
        val channel = MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL)
        channel.setMethodCallHandler { call, result ->
            when (call.method) {
                "getOpenFileUrl" -> {
                    result.success(openPath)
                }
                else -> result.notImplemented()
            }
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        handleOpenFileUrl(intent)
    }

    override fun onNewIntent(intent: Intent) {
        super.onNewIntent(intent)
        handleOpenFileUrl(intent)
    }

    private fun handleOpenFileUrl(intent: Intent?) {
        val path = intent?.data?.path
        if (path != null) {
            openPath = path
        }
    }
}

颤振：

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

class _MyHomePageState extends State<MyHomePage> with WidgetsBindingObserver {
  static const platform =
      const MethodChannel('tinyappsteam.flutter.dev/open_file');

  String openFileUrl;

  @override
  void initState() {
    super.initState();
    getOpenFileUrl();
    // Listen to lifecycle events.
    WidgetsBinding.instance.addObserver(this);
  }

  @override
  void dispose() {
    super.dispose();
    WidgetsBinding.instance.removeObserver(this);
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      getOpenFileUrl();
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Text("Audio file: " + (openFileUrl != null ? openFileUrl : "Nothing!")),
      ),
    );
  }

  void getOpenFileUrl() async {
    dynamic url = await platform.invokeMethod("getOpenFileUrl");
    print("getOpenFileUrl");
    if (url != null && url != openFileUrl) {
      setState(() {
        openFileUrl = url;
      });
    }
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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