Great question! You absolutely don’t need extra plugins to get your Flutter music player showing up in "Open with" or "Share to" menus. You can achieve this by configuring the native platform’s manifest files directly and adding lightweight Dart code to handle incoming intents or URLs—no heavy dependencies required. Let’s walk through the setup for both Android and iOS:

1. Update AndroidManifest.xml #

First, tell the Android system your app can handle audio files by adding an intent-filter to your main activity. This registers your app for "Open with" (via VIEW action) and "Share to" (via SEND action) workflows.

Open android/app/src/main/AndroidManifest.xml and add this inside your <activity> tag:

<intent-filter>
    <action android:name="android.intent.action.VIEW" />
    <action android:name="android.intent.action.SEND" />
    <category android:name="android.intent.category.DEFAULT" />
    <!-- Catch all audio types, or specify individual formats -->
    <data android:mimeType="audio/*" />
    <data android:mimeType="audio/mpeg" /> <!-- MP3 -->
    <data android:mimeType="audio/flac" /> <!-- FLAC -->
</intent-filter>

2. Handle Intents in Dart #

Use a lightweight MethodChannel to pass incoming intent data from Android to Dart (no plugins needed—just a few lines of native code).

Add Dart code to listen for intents:

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

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  
  // Check for intent when the app first launches
  _handleInitialIntent();
  
  // Listen for new intents while the app is running
  SystemChannels.lifecycle.setMessageHandler((msg) async {
    if (msg == AppLifecycleState.resumed.toString()) {
      _handleLatestIntent();
    }
    return null;
  });
  
  runApp(const MyMusicPlayerApp());
}

// MethodChannel to communicate with Android
const _channel = MethodChannel('com.yourdomain.musicplayer/intent');

Future<void> _handleInitialIntent() async {
  final intentData = await _channel.invokeMethod<String>('getInitialIntent');
  if (intentData != null) {
    _processAudioFile(intentData);
  }
}

Future<void> _handleLatestIntent() async {
  final intentData = await _channel.invokeMethod<String>('getLatestIntent');
  if (intentData != null) {
    _processAudioFile(intentData);
  }
}

void _processAudioFile(String fileUri) {
  // Parse the URI, load the audio file, and handle playback/sharing logic
  print('Received audio file: $fileUri');
}

Add native Android code to pass intent data:

Open android/app/src/main/kotlin/[your-package]/MainActivity.kt and update it with:

import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugin.common.MethodChannel
import android.content.Intent

class MainActivity : FlutterActivity() {
    private val CHANNEL = "com.yourdomain.musicplayer/intent"
    private var latestIntent: Intent? = null

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)
        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL).setMethodCallHandler { call, result ->
            when (call.method) {
                "getInitialIntent" -> result.success(intent.data?.toString())
                "getLatestIntent" -> result.success(latestIntent?.data?.toString())
                else -> result.notImplemented()
            }
        }
    }

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

1. Update Info.plist #

Tell iOS your app can handle audio files by adding document type declarations and sharing support.

Open ios/Runner/Info.plist and add these entries:

<!-- Register support for audio files -->
<key>CFBundleDocumentTypes</key>
<array>
    <dict>
        <key>CFBundleTypeName</key>
        <string>Audio Files</string>
        <key>LSHandlerRank</key>
        <string>Alternate</string>
        <key>LSItemContentTypes</key>
        <array>
            <string>public.audio</string>
            <string>public.mp3</string>
            <string>public.flac</string>
        </array>
    </dict>
</array>

<!-- Enable file sharing support -->
<key>UIFileSharingEnabled</key>
<true/>
<key>LSSupportsOpeningDocumentsInPlace</key>
<true/>

<!-- Support share-to workflows -->
<key>NSUserActivityTypes</key>
<array>
    <string>com.apple.coreui.services.openurl</string>
</array>

2. Handle URLs in Dart #

Again, use a MethodChannel to pass incoming file URLs from iOS to Dart.

Add Dart code to listen for URLs:

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

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  
  const _channel = MethodChannel('com.yourdomain.musicplayer/url');
  
  // Check for initial URL on launch
  _channel.invokeMethod<String>('getInitialUrl').then((url) {
    if (url != null) _processAudioFile(url);
  });
  
  // Listen for new URLs while the app is running
  _channel.setMethodCallHandler((call) async {
    if (call.method == 'onUrlReceived') {
      final url = call.arguments as String;
      _processAudioFile(url);
    }
    return null;
  });
  
  runApp(const MyMusicPlayerApp());
}

void _processAudioFile(String fileUrl) {
  // Parse the URL, access the local file, and handle playback/sharing
  print('Received audio file: $fileUrl');
}

Add native iOS code to pass URL data:

Open ios/Runner/AppDelegate.swift and update it with:

import UIKit
import Flutter

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
    private let CHANNEL = "com.yourdomain.musicplayer/url"
    private var latestUrl: URL?

    override func application(
        _ application: UIApplication,
        didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
    ) -> Bool {
        let controller = window?.rootViewController as! FlutterViewController
        let channel = FlutterMethodChannel(name: CHANNEL, binaryMessenger: controller.binaryMessenger)
        
        channel.setMethodCallHandler { [weak self] call, result in
            switch call.method {
            case "getInitialUrl":
                let url = launchOptions?[.url] as? URL
                result(url?.absoluteString)
            default:
                result(FlutterMethodNotImplemented)
            }
        }

        GeneratedPluginRegistrant.register(with: self)
        return super.application(application, didFinishLaunchingWithOptions: launchOptions)
    }

    override func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
        latestUrl = url
        _sendUrlToFlutter(url: url)
        return true
    }

    override func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void) -> Bool {
        if let url = userActivity.webpageURL {
            latestUrl = url
            _sendUrlToFlutter(url: url)
        }
        return true
    }

    private func _sendUrlToFlutter(url: URL) {
        let controller = window?.rootViewController as! FlutterViewController
        let channel = FlutterMethodChannel(name: CHANNEL, binaryMessenger: controller.binaryMessenger)
        channel.invokeMethod("onUrlReceived", arguments: url.absoluteString)
    }
}

• This approach uses only Flutter’s built-in MethodChannel and native platform configuration—no third-party plugins, so performance stays snappy.
• For both platforms, you’ll need to handle file permissions (like accessing external storage on Android or document directories on iOS) if the audio file is outside your app’s sandbox.
• Test thoroughly by sharing an audio file from another app or selecting "Open with" from your device’s file manager.

内容的提问来源于stack exchange，提问作者Kaki Master Of Time