Flutter Android Bindings

This is a Flutter plugin for using Android's numerous platform-specific APIs in Flutter apps.

Prerequisites

• Dart 2.8+ and Flutter 1.17+

Compatibility

Android only.

Installation

dependencies:
  flutter_android: ^0.8.0

Features

• Implements bindings to a growing set of Android's platform-specific APIs.

• Reduces duplication of effort by centralizing Android bindings in a single package.

Feature Table

Examples

Activity launch

import 'package:flutter_android/android_content.dart' show Intent;

await Intent(
  action: "android.intent.action.VIEW", // Intent.ACTION_VIEW
  data: Uri.parse("https://flutter.dev"),
).startActivity();

Parcel serialization

import 'package:flutter_android/android_os.dart' show Parcel;

var parcel = Parcel.obtain()
  ..writeBoolean(true)
  ..writeInt(42)
  ..writeDouble(3.1415)
  ..writeString("Hello, world!")
  ..writeList(<Object>[1, 2, 3])
  ..writeMap(<String, Object>{"a": 1, "b": 2, "c": 3});

await _channel.invokeMethod('someJavaMethod', parcel.asUint8List());

// In Java, your MethodCallHandler's call.arguments contains the marshaled Parcel

Face detection

import 'package:flutter_android/android_graphics.dart' show Bitmap;
import 'package:flutter_android/android_media.dart' show Face, FaceDetector;

var photo = Image.asset("images/einstein.png");

var bitmap = Bitmap.fromAssetImage(photo.image as AssetImage);
var detector = FaceDetector(width: 280, height: 396);

for (var face in await detector.findFaces(bitmap)) {
  if (face.confidence < Face.CONFIDENCE_THRESHOLD) {
    continue; // skip dubious results below the cut-off threshold
  }
  print("Found a face at (${face.midPoint.x}, ${face.midPoint.y}) with confidence ${face.confidence}");
}

Heart-rate monitoring

import 'package:flutter_android/android_hardware.dart'
    show Sensor, SensorEvent, SensorManager;

var sensor = await SensorManager.getDefaultSensor(Sensor.TYPE_HEART_RATE);

var events = await sensor.subscribe();
events.listen((SensorEvent event) {
  print(event.values[0]);
});

Frequently Asked Questions

TODO

Caveats

• iOS is not and cannot be supported. All flutter_android APIs throw an AssertionError if they are invoked when running on iOS. For cross-platform apps, we recommend that you depend on the platform package to conditionalize your use of Android APIs.

Reference

android

import 'package:flutter_android/android.dart' as android;

android_app

import 'package:flutter_android/android_app.dart' as android_app;

• Notification
• NotificationAction
• WallpaperColors

android_bluetooth

import 'package:flutter_android/android_bluetooth.dart' as android_bluetooth;

• BluetoothAdapter
• BluetoothDevice
• BluetoothHeadset
• BluetoothLeScanner
• BluetoothManager

android_content

import 'package:flutter_android/android_content.dart' as android_content;

• ComponentName
• ContentValues
• Context.cacheDir
• Context.codeCacheDir
• Context.dataDir
• Context.externalCacheDir
• Context.externalFilesDir
• Context.filesDir
• Context.getSharedPreferences()
• Context.getSystemService()
• Context.noBackupFilesDir
• Context.packageCodePath
• Context.packageName
• Context.packageResourcePath
• Intent
• SharedPreferences

android_database

import 'package:flutter_android/android_database.dart' as android_database;

• Cursor
• DatabaseUtils
• MatrixCursor

android_graphics

import 'package:flutter_android/android_graphics.dart' as android_graphics;

• Bitmap
• Point
• PointF

android_hardware

import 'package:flutter_android/android_hardware.dart' as android_hardware;

• Sensor
• SensorEvent
• SensorEventListener
• SensorManager

android_location

import 'package:flutter_android/android_location.dart' as android_location;

• Location

android_media

import 'package:flutter_android/android_media.dart' as android_media;

• Face
• FaceDetector

android_os

import 'package:flutter_android/android_os.dart' as android_os;

• Bundle
• Environment.dataDirectory
• Environment.downloadCacheDirectory
• Environment.externalStorageDirectory
• Environment.externalStorageState
• Environment.rootDirectory
• Environment.isExternalStorageEmulated
• Environment.isExternalStorageRemovable

Cross-Reference

See Also

• The win32 package provides bindings to the most common Win32 APIs.