Android bindings plugin for Flutter

flutter android bindings

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 bindings

android only.

installation

dependencies:
  flutter_android: ^0.8.0

features

android bindings

• 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

android bindings

feature	flutter api
activity launch	android_content.intent#startactivity()
bluetooth scanning	android_bluetooth.bluetoothlescanner
distance calculation	android_location.location.distancebetween()
face detection	android_media.facedetector
heart-rate monitoring	android_hardware.sensormanager.getdefaultsensor()
parcel serialization	android_os.parcel
sensor event streams	android_hardware.sensor#subscribe()

todo: dirs

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

android	flutter
android.app	android_app
android.app.activity	android_app.activity
android.app.activitymanager	android_app.activitymanager
android.app.alarmmanager	android_app.alarmmanager
android.app.authenticationrequiredexception	android_app.authenticationrequiredexception
android.app.downloadmanager	android_app.downloadmanager
android.app.keyguardmanager	android_app.keyguardmanager
android.app.notification	android_app.notification
android.app.notification.action	android_app.notificationaction
android.app.notification.builder	android_app.notificationbuilder
android.app.notificationmanager	android_app.notificationmanager
android.app.pendingintent	android_app.pendingintent
android.app.searchmanager	android_app.searchmanager
android.app.wallpapercolors	android_app.wallpapercolors
android.app.wallpaperinfo	android_app.wallpaperinfo
android.app.wallpapermanager	android_app.wallpapermanager
android.bluetooth	android_bluetooth
android.bluetooth.bluetoothadapter	android_bluetooth.bluetoothadapter
android.bluetooth.bluetoothdevice	android_bluetooth.bluetoothdevice
android.bluetooth.bluetoothheadset	android_bluetooth.bluetoothheadset
android.bluetooth.bluetoothmanager	android_bluetooth.bluetoothmanager
android.bluetooth.le.bluetoothlescanner	android_bluetooth.bluetoothlescanner
android.bluetooth.le	android_bluetooth
android.content	android_content
android.content.activitynotfoundexception	android_content.activitynotfoundexception
android.content.componentname	android_content.componentname
android.content.contentvalues	android_content.contentvalues
android.content.context	android_content.context
android.content.intent	android_content.intent
android.content.intentfilter	android_content.intentfilter
android.content.sharedpreferences	android_content.sharedpreferences
android.database	android_database
android.database.cursor	android_database.cursor
android.database.cursorindexoutofboundsexception	android_database.cursorindexoutofboundsexception
android.database.databaseutils	android_database.databaseutils
android.database.matrixcursor	android_database.matrixcursor
android.database.sqlexception	android_database.sqlexception
android.graphics	android_graphics
android.graphics.bitmap	android_graphics.bitmap
android.graphics.color	dart-ui.color
android.graphics.point	android_graphics.point
android.graphics.pointf	android_graphics.pointf
android.graphics.drawable.icon	flutter.icon
android.hardware	android_hardware
android.hardware.sensor	android_hardware.sensor
android.hardware.sensorevent	android_hardware.sensorevent
android.hardware.sensoreventlistener	android_hardware.sensoreventlistener
android.hardware.sensormanager	android_hardware.sensormanager
android.location	android_location
android.location.location	android_location.location
android.media	android_media
android.media.facedetector	android_media.facedetector
android.media.facedetector.face	android_media.face
android.net	android_net
android.nfc	android_nfc
android.os	android_os
android.os.batterymanager	android_os.batterymanager
android.os.build	android_os.build
android.os.bundle	android_os.bundle
android.os.environment	android_os.environment
android.os.hardwarepropertiesmanager	android_os.hardwarepropertiesmanager
android.os.parcel	android_os.parcel
android.os.parcelable	android_os.parcelable
android.os.powermanager	android_os.powermanager
android.os.process	android_os.process
android.os.statfs	android_os.statfs
android.os.systemclock	android_os.systemclock
android.os.usermanager	android_os.usermanager
android.os.vibrationeffect	android_os.vibrationeffect
android.os.vibrator	android_os.vibrator
android.provider	android_provider
android.security	android_security
android.speech	android_speech
android.telephony	android_telephony
android.view	android_view
java.util.locale	dart-ui.locale