android_content_provider 0.2.2

Flutter plugin to use ContentProvider/ContentResolver APIs on Android

example/lib/main.dart

///
/// This example shows off fetching songs from MediaStore with [AndroidContentResolver],
/// and declaring (and calling to) your own [AndroidContentProvider].
///
///

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:android_content_provider/android_content_provider.dart';
import 'package:permission_handler/permission_handler.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Permission.storage.request();
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  List<List<Object?>>? songs;

  @override
  void initState() {
    super.initState();
    callToMyAndroidContentProvider();
    fetch();
  }

  /// Calls [MyAndroidContentProvider.delete].
  ///
  /// This could have been called by some other app to access our app's functions.
  Future<void> callToMyAndroidContentProvider() async {
    await AndroidContentResolver.instance.delete(
      uri:
          'content://com.nt4f04und.android_content_provider_example.MyAndroidContentProvider/some_uri',
    );
  }

  void fetch() async {
    final cursor = await AndroidContentResolver.instance.query(
      // MediaStore.Audio.Media.EXTERNAL_CONTENT_URI
      uri: 'content://media/external/audio/media',
      projection: ['_id', 'title'],
      selection: null,
      selectionArgs: null,
      sortOrder: null,
    );
    try {
      final end = (await cursor!.batchedGet().getCount().commit()).first as int;
      final batch = cursor.batchedGet().getInt(0).getString(1);

      // Fast!
      // While a bit less flexible, commitRange is much faster (approximately 10x)
      await measure(() async {
        songs = await batch.commitRange(0, end);
      });

      if (mounted) {
        setState(() {
          // We loaded the songs.
        });
      }

      // Slow!
      // But can be useful for lots of atomic operations on large cursors.
      var slowSongs = [];
      await measure(() async {
        while (await cursor.moveToNext()) {
          slowSongs.add(await batch.commit());
        }
      });

      // Prints true
      final same = slowSongs.toString() == songs.toString();
      debugPrint('$same');
    } finally {
      cursor?.close();
    }
  }

  Future<void> measure(Function callback) async {
    final s = Stopwatch();
    s.start();
    await callback();
    s.stop();
    debugPrint('elapsed ${s.elapsedMilliseconds}');
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('AndroidContentProvider plugin example'),
        ),
        body: songs == null
            ? const SizedBox.shrink()
            : ListView.builder(
                itemExtent: 50,
                itemCount: songs!.length,
                itemBuilder: (context, index) => ListTile(
                  title: Text(songs![index].last as String),
                ),
              ),
      ),
    );
  }
}

class MyAndroidContentProvider extends AndroidContentProvider {
  MyAndroidContentProvider(String authority) : super(authority);

  @override
  Future<int> delete(
    String uri,
    String? selection,
    List<String>? selectionArgs,
  ) async {
    debugPrint('delete uri $uri');
    return 0;
  }

  @override
  Future<String?> getType(String uri) async {
    return null;
  }

  @override
  Future<String?> insert(String uri, ContentValues? values) async {
    return null;
  }

  @override
  Future<CursorData?> query(
    String uri,
    List<String>? projection,
    String? selection,
    List<String>? selectionArgs,
    String? sortOrder,
  ) async {
    return null;
  }

  @override
  Future<int> update(
    String uri,
    ContentValues? values,
    String? selection,
    List<String>? selectionArgs,
  ) async {
    return 0;
  }
}

@pragma('vm:entry-point')
void exampleContentProviderEntrypoint() {
  MyAndroidContentProvider(
    'com.nt4f04und.android_content_provider_example.MyAndroidContentProvider',
  );
}