Large File Handler Plugin #

The Large File Handler Plugin designed to efficiently work with large files, for example allows you to download large files from network or copy files from the Flutter app's assets to the device's local file system. This is useful when you need to access large files at native part in your plugins.

Features #

• Copy any asset from your Flutter project to the local file system.
• Download files from a network to the local file system.
• Cross-platform support: Android, iOS, macOS, Windows, and Linux.
• Copy files with or without progress tracking.

Installation #

To install the plugin, add the following line to your pubspec.yaml under the dependencies section:

dependencies:
  large_file_handler: ^0.5.0

Then, run:

flutter pub get

Usage with assets #

1. Register the asset in pubspec.yaml #

Make sure the asset file is registered in your Flutter app. Add the following lines to the pubspec.yaml:

flutter:
  assets:
    - assets/example.json

2. Copy asset to native local file system #

Without progress tracking:

Use the plugin to copy the asset to a local path on the device:

import 'package:large_file_handler/large_file_handler.dart';

Future<void> copyAssetToLocal() async {
  String status;
  try {
    const assetName = 'example.json';
    const targetPath = 'example.json';

    await LargeFileHandler().copyAssetToLocalStorage(assetName: assetName, targetPath: targetPath);
    status = 'File copied successfully to $targetPath';
  } on PlatformException catch (e) {
    status = 'Failed to copy asset: ${e.message}';
  }
}

With progress tracking:

You can also track the progress of copying the asset using the stream:

import 'package:large_file_handler/large_file_handler.dart';

Future<void> copyAssetToLocalWithProgress() async {
  String status;
  try {
    const assetName = 'example.json';
    const targetPath = 'example.json';

    final progressStream = LargeFileHandler().copyAssetToLocalStorageWithProgress(assetName: assetName, targetPath: targetPath);
    progressStream.listen((progress) {
      print('Progress: $progress%');
    });
  } on PlatformException catch (e) {
    status = 'Failed to copy asset: ${e.message}';
  }
}

Usage with network #

1. Upload an asset to network storage #

Make sure the asset file is uploaded to network or cloud storage.

2. Download asset to native local file system #

Without progress tracking:

Use the plugin to download the asset to a local path on the device:

import 'package:large_file_handler/large_file_handler.dart';

Future<void> copyCloudToLocal() async {
  String status;
  try {
    const url = 'https://cloud/example.json';
    const targetPath = 'example.json';

    await LargeFileHandler().copyNetworkAssetToLocalStorage(assetUrl: url, targetPath: targetPath);
    status = 'File downloaded successfully to $targetPath';
  } on PlatformException catch (e) {
    status = 'Failed to download asset: ${e.message}';
  }
}

With progress tracking:

You can also track the progress of downloading the file:

import 'package:large_file_handler/large_file_handler.dart';

Future<void> copyCloudToLocal() async {
  String status;
  try {
    const url = 'https://cloud/example.json';
    const targetPath = 'example.json';

    final progressStream = LargeFileHandler().copyNetworkAssetToLocalStorageWithProgress(assetUrl: url, targetPath: targetPath);
    progressStream.listen((progress) {
      print('Download progress: $progress%');
    });
  } on PlatformException catch (e) {
    status = 'Failed to download asset: ${e.message}';
  }
}

Supported Platforms #

Web #

A browser has no application documents directory, so this plugin cannot copy or download files to a local file path on web. Every method throws an UnsupportedError. Guard your calls with kIsWeb, or catch the error:

import 'package:flutter/foundation.dart' show kIsWeb;

if (!kIsWeb) {
  await LargeFileHandler().copyAssetToLocalStorage(
    assetName: 'example.json',
    targetPath: 'example.json',
  );
}

License #

This plugin is released under the MIT license. See the LICENSE file for details.