Implementing improvements to the debug notification on Android.

• The first information notification should be removed if the result notification was posted.
• Show elapsed time in seconds between starting the Flutter engine and receiving the result.
• Emoji's!
• Use the date formatter of the user
• Provide a sample screenshot in the ANDROID_README

When a background task was scheduled it is difficult to trace/debug whether this task actually ran.
When a task runs on Android 2 notifications are shown:

• The first one appears when a the background task was launched in native side. This is called before Flutter Engine is started. We output some useful information this includes:
  • dartTask
    This was the value the task was scheduled with during registerOneOffTask or registerPeriodicTask and outputted to the executeTask method. On iOS this irrelevant.
  • callbackHandle:
    This is the raw int handle that was saved during the initialize method
  • callBackName:
    This is the name of the callbackDispatcher function. If a user renamed this in between runs this would be very helpful debug information.
  • callbackClassName:
    The name (if any) of the class this callbackDispatcher resides in.
  • callbackLibraryPath:
    The filename of where the callbackDispatcher resides.
  • dartBundlePath:
    The path where of the Dart code inside the binary.
• The second notification is scheduled when the Result is returned from the callbackDispatcher.

Example of Android debug notifications:

The idea would be to get the same behaviour on iOS too.

Some improvements will be made:

• Show the elapsed time in seconds between starting the callback and retrieving the answer (so you know how long your background task ran, this should be as little as possible)
• Emoji's for quick glancing to see if it returned a success or a failure
• Stacks, combine logical grouping of notification
• Remove the first notification with the information if the result is received.
• Local Local formatting for time
• Don't forget to show an example screenshot of what a user can expect in the IOS_README

Android improvement ticket #36

I'm running a periodic task and it works perfectly. However during the night I usually turn on airplane mode and turn it off in the morning. From that point on I do not receive notifications again.

If I register a task with a 5-minute initial delay and killing the app before this time reaches, will the task still be executed?

As discovered in #4.
flutter_workmanager: 0.0.6+1

It seems like it is currently impossible to use other plugins inside your background task as they are not registered.

[ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: MissingPluginException(No implementation found for method FirebaseApp#appNamed on channel plugins.flutter.io/firebase_core)

Simple example:

pubspec:

name: workmanager_example
description: Demonstrates how to use the workmanager plugin.
publish_to: 'none'

environment:
  sdk: ">=2.1.0 <3.0.0"

dependencies:
  path_provider: ^1.2.0
  workmanager: 0.0.6+1
  flutter:
    sdk: flutter
  cupertino_icons: ^0.1.2

flutter:
  uses-material-design: true

main.dart

import 'dart:io';
import 'package:path_provider/path_provider.dart';
import 'dart:async';

import 'package:workmanager/workmanager.dart';

void callbackDispatcher() {
  Workmanager.defaultCallbackDispatcher((echoValue) async {
    switch (echoValue) {
      case simpleTaskKey:
        Directory tempDir = await getTemporaryDirectory();
        String tempPath = tempDir.path;
        break;
    }

    return Future.value(true);
  });
}

OK. So, the install instructions aren't very through for mortals like me so this is what I did:
1 - create new flutter app (run, test, OK)
2 - added workmanager: ^0.0.15 to the dependencies (get packages, ok)
3 - created a file called App.kt under android.app.source.main.java.myproject.com.projectname along with the MainActivity.java file
4 - copy the file from readme to App.kt
5 - change AndroidManifest.xml under android.app.source.main android:name=".App"
6 - run app
7 - emulator blinks as if it was opening an app and them goes back to the device screen
8 - console says: Installing build\app\outputs\apk\app.apk... and stays there

What am I missing here?

Hey guys,

I tried to run the example as well as my own version. Android works fine but I can't get the simulator to run notifications never. Is there some trick with simulator or do I have to use real device?

Also, the option to dispatch fetch in xcode is greyed out for me, so I couldn't try that one from the docs.

Failed to compile version 0.0.12

android/src/main/kotlin/be/tramckrijte/workmanager/WorkmanagerCallHandler.kt: (22, 19): The feature "variable declaration in when subject" is only available since language version 1.3

If you are having this issue. Upgrade your Kotlin version of 1.3 or above for your project.

I tried to integrate the dummy code example in my App:

void callbackDispatcher() {
  Workmanager.executeTask((backgroundTask) {
    print("Native called background task: $backgroundTask"); //simpleTask will be emitted here.
    return Future.value(true);
  });
}

void main() {
  Workmanager.initialize(
    callbackDispatcher, // The top level function, aka callbackDispatcher
    isInDebugMode: true // If enabled it will post a notification whenever the task is running. Handy for debugging tasks
  );
  Workmanager.registerOneOffTask("1", "simpleTask");
  runApp(MyApp());
}

But I got the following error while starting:

E/AndroidRuntime(27923): kotlin.UninitializedPropertyAccessException: lateinit property pluginRegistryCallback has not been initialized
E/AndroidRuntime(27923): 	at be.tramckrijte.workmanager.WorkmanagerPlugin$Companion.getPluginRegistryCallback(WorkmanagerPlugin.kt:13)
E/AndroidRuntime(27923): 	at be.tramckrijte.workmanager.BackgroundWorker$doWork$1.run(BackgroundWorker.kt:71)
E/AndroidRuntime(27923): 	at android.os.Handler.handleCallback(Handler.java:751)
E/AndroidRuntime(27923): 	at android.os.Handler.dispatchMessage(Handler.java:95)
E/AndroidRuntime(27923): 	at android.os.Looper.loop(Looper.java:154)
E/AndroidRuntime(27923): 	at android.app.ActivityThread.main(ActivityThread.java:6682)
E/AndroidRuntime(27923): 	at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime(27923): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1520)
E/AndroidRuntime(27923): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1410)

As I mention in issue #45: we should expand our documentation:

• Expand on the Simulate Background Fetch option in Xcode: only works if debugger is attached to the Runner process
• Explain that, by default, notifications are not shown when the app is running in the foreground. Point to relevant Apple docs

As mentioned in #45: if the example app is running in the foreground while simulating a background fetch in Xcode, the notification banner isn't shown. That is default behaviour on iOS.

Triggering Simulate Background Fetch when running on a real device will put the app in the background automatically for you. This doesn't happen in the simulator for some reason 🤷‍♂️

If you do want the banners to appear while your app is in the foreground you can implement userNotificationCenter(_:willPresent:withCompletionHandler:) of UNUserNotificationCenterDelegate.

From the Apple docs:

If your app is in the foreground when a notification arrives, the shared user notification center calls this method to deliver the notification directly to your app. If you implement this method, you can take whatever actions are necessary to process the notification and update your app. When you finish, call the completionHandler block and specify how you want the system to alert the user, if at all.

The example app should implement this delegate call, and it's definitely something we should mention in our documentation (see #46) as well.

workmanager: ^0.1.1

E/AndroidRuntime( 6854): kotlin.UninitializedPropertyAccessException: lateinit property pluginRegistryCallback has not been initialized

[√] Flutter (Channel master, v1.10.2-pre.83, on Microsoft Windows [versão 10.0.18362.356], locale pt-BR)
[√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[√] Android Studio (version 3.5)
[√] VS Code (version 1.37.0)
[√] Connected device (1 available)

After initialising the the workmanager and creating either of the tasks, If we use any plugins inside of the task execution it isn't recognised and throw an error as bellow
MissingPluginException(No implementation found for method getLocation on channel lyokone/location)

Actual code :
Workmanager.executeTask((task, inputData) async { Location locationObject = Location(); locationObject.getLocation(); print(locationObject); return Future.value(true); }

Basically any other plugin used inside of the task of work manager seems to be not recognised.

What am I missing, Do I need to register all my plugins again ?

Currently the CallbackHandle is stored in the standard UserDefaults, it might be better to not 'dirty' up the standard UserDefaults but to instead store any necessary info in a separate suite specifically for the plugin.

It would also be safer to prefix certain Strings with the plugin's identifier, to make them more unique. More specifically:

• The callbackHandleStorageKey used to store a callback handle in the UserDefaults
• The flutterThreadLabelPrefix used to initialise a FlutterEngine

Relevant excerpt from the FlutterEngine.hfile:

 * @param labelPrefix The label prefix used to identify threads for this instance. Should
 *   be unique across FlutterEngine instances, and is used in instrumentation to label
 *   the threads used by this FlutterEngine.
 * @param projectOrNil The `FlutterDartProject` to run.
 */
- (instancetype)initWithName:(NSString*)labelPrefix project:(FlutterDartProject*)projectOrNil;

Regarding Android setup process, is it possible to add default working custom application to plugin so that ppl only need to change application name and save the step to create an application class everytime?

Hi,
I am getting this error when trying to run the app on IOS.

Unable to determine Swift version for the following pods:
    - `workmanager` does not specify a Swift version and none of the targets (`Runner`) integrating it have the `SWIFT_VERSION` attribute set.
Please contact the author or set the `SWIFT_VERSION` attribute in at least one of the targets that integrate this pod.

Currently BackgroundTaskHandler's signature is defined like so:

typedef BackgroundTaskHandler = Future<bool> Function(String taskName);

But in the iOS implementation the bool result is interpreted as an Int:
let fetchResult: Int = flutterResult as? Int

Causing a wrong UIBackgroundFetchResult to be created. Also relates to #20.

In our testing we noticed an issue with delivery of the local debug notifications.

We see a lot of "👷‍♀️ work started" notifications but no "🔥/ 🎉 work finished" notifications (finished should overwrite started notifications). When, at a later point we open the app we immediately see the work finished notification coming in.

The timestamps and elapsed times are all correct, so it's definitely a notification delivery issue. The actual background fetch did run correctly.

I'm getting this error, am I missing something?

Application.java:12: error: cannot find symbol
    WorkmanagerPlugin.setPluginRegistrantCallback(this);
                     ^
  symbol:   method setPluginRegistrantCallback(Application)
  location: class WorkmanagerPlugin
1 error

FAILURE: Build failed with an exception.

Application.java

package`package_name`;

import be.tramckrijte.workmanager.WorkmanagerPlugin;
import io.flutter.app.FlutterApplication;
import io.flutter.plugin.common.PluginRegistry;
import io.flutter.plugins.GeneratedPluginRegistrant;

public class Application extends FlutterApplication implements PluginRegistry.PluginRegistrantCallback {
  @Override
  public void onCreate() {
    super.onCreate();
    WorkmanagerPlugin.setPluginRegistrantCallback(this);
  }

  @Override
  public void registerWith(PluginRegistry registry) {
    GeneratedPluginRegistrant.registerWith(registry);
  }
}

I've added the custom application to android manifest.

I have the dependency: workmanager: ^0.0.11

There is not a WorkManagerConstraintConfig in the version ^0.0.15 Is it replaced with Constraints?

I assume this issue could be relevant not only for flutter_webview_plugin ,but still.
I have listeners attached to flutter_webview_plugin. For example onUrlChanged and onStateChanged. All works fine until I call Workmanager.initialize().
No errors. Just listeners stops working.

I'm using workmanager: ^0.1.0

Getting an error calling initialize method:

MissingPluginException(No implementation found for method initialize on channel be.tramckrijte.workmanager/foreground_channel_work_manager)

My main.dart:

import 'package:workmanager/workmanager.dart' as workManager;

...

void main() async {
  FlutterError.onError = (errorDetails) {
    Logger.e( "${errorDetails.exception}");
    if (Logger.isInDebugMode) {
      FlutterError.dumpErrorToConsole(errorDetails);
    }
  };

  runZoned(() {
    workManager.Workmanager.initialize(
        LocationManager.updateDeviceLocationIsolate,
        isInDebugMode: Logger.isInDebugMode
    );
    runApp(new HAClientApp());

  }, onError: (error, stack) {
    Logger.e("$error");
    Logger.e("$stack");
    if (Logger.isInDebugMode) {
      debugPrint("$stack");
    }
  });
}

...

My Application.java:

package com.keyboardcrumbs.hassclient;

import io.flutter.app.FlutterApplication;
import io.flutter.plugin.common.PluginRegistry;
import io.flutter.plugin.common.PluginRegistry.PluginRegistrantCallback;
import io.flutter.plugins.GeneratedPluginRegistrant;
import be.tramckrijte.workmanager.WorkmanagerPlugin;

public class Application extends FlutterApplication implements PluginRegistrantCallback {
    @Override
    public void onCreate() {
        super.onCreate();
        WorkmanagerPlugin.setPluginRegistrantCallback(this);
    }

    @Override
    public void registerWith(PluginRegistry registry) {
        GeneratedPluginRegistrant.registerWith(registry);
    }
}

Part of my AndroidManifest.xml:

....

<application
        android:name=".Application"
        android:label="HA Client"
        android:icon="@mipmap/ic_launcher"
        android:usesCleartextTraffic="true">

...

Actually this was an idea we already discussed with @jeremie-movify and @petermnt before.
The return of a boolean as the result of a background job was a MVP approach and might be insufficient.

Ideally we would want to return some sort of enum representing the success state of a background task.

Android already expects either a:

• Result.failure()

  • Used to indicate that the work completed with a permanent failure. Any work that depends
    on this will also be marked as failed and will not be run. If you need child workers
    to run, you need to return Result.Success() failure indicates a permanent
    stoppage of the chain of work.

• Result.success()

  • Used to indicate that the work completed successfully. Any work that depends on this
    can be executed as long as all of its other dependencies and constraints are met.

• Result.Retry()

  • Used to indicate that the work encountered a transient failure and should be retried with
    backoff.

As of now (0.0.12) the plugin will map the returning bool as following:

• false -> Result.retry()
• true -> Result.success()

I thought the iOS return code was similarly mapped.

We could then have something like:

void callbackDispatcher() {
  var result = Result.retry
  Workmanager.executeTask((task) async {
    switch (task) {
      case simpleTaskKey:
       print("do some background work");
       result = Result.success
        break;
    }

    return Future.value(result);
  });
}

Originally posted by @timrijckaert in #20 (comment)

Crash when using cancelAll.

ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: MissingPluginException(No implementation found for method cancelAll on channel be.tramckrijte.workmanager/foreground_channel_work_manager)
E/flutter (17937): #0      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:314:7)
E/flutter (17937): <asynchronous suspension>
E/flutter (17937): #1      Workmanager.cancelAll (package:workmanager/src/workmanager.dart:163:32)
E/flutter (17937): <asynchronous suspension>
E/flutter (17937): #2      BackgroundWorker.cancelAll (package:flutter_template/background/background.dart:60:42)
E/flutter (17937): #3      _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:635:14)
E/flutter (17937): #4      _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:711:32)
E/flutter (17937): #5      GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
E/flutter (17937): #6      TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:365:11)
E/flutter (17937): #7      TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:275:7)
E/flutter (17937): #8      PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:455:9)
E/flutter (17937): #9      PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:75:13)
E/flutter (17937): #10     PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:102:11)
E/flutter (17937): #11     _WidgetsFlutterBinding&BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:218:19)
E/flutter (17937): #12     _WidgetsFlutterBinding&BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22)
E/flutter (17937): #13     _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7)
E/flutter (17937): #14     _WidgetsFlutterBinding&BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7)
E/flutter (17937): #15     _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)
E/flutter (17937): #16     _rootRunUnary (dart:async/zone.dart:1136:13)
E/flutter (17937): #17     _CustomZone.runUnary (dart:async/zone.dart:1029:19)
E/flutter (17937): #18     _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
E/flutter (17937): #19     _invoke1 (dart:ui/hooks.dart:250:10)
E/flutter (17937): #20     _dispatchPointerDataPacket (dart:ui/hooks.dart:159:5)

Congratulations for the work. This is the only background solution I know.

Could you give us the freedom to configure the notification that appears after starting the service? How to choose the icon, title and be able to generate a link by clicking on it? How to generate a link to open the app.

With this PR =)
#79

Error output from Xcode build:
↳
** BUILD FAILED **

Xcode's output:
↳
/Users/apple/git_flutter/flutter/.pub-cache/hosted/pub.flutter-io.cn/workmanager-0.1.0/ios/Classes/SwiftWorkmanagerPlugin.swift:98:156: error: argument type 'FlutterEngine' does not conform to expected type 'FlutterBinaryMessenger'
var backgroundMethodChannel: FlutterMethodChannel? = FlutterMethodChannel(name: BackgroundMethodChannel.channelName, binaryMessenger: flutterEngine!)
~~~~~~~~~~~~~^
as! FlutterBinaryMessenger

E/AndroidRuntime(28568): kotlin.UninitializedPropertyAccessException: lateinit property pluginRegistryCallback has not been initialized
E/AndroidRuntime(28568): at be.tramckrijte.workmanager.WorkmanagerPlugin$Companion.getPluginRegistryCallback(WorkmanagerPlugin.kt:13)
E/AndroidRuntime(28568): at be.tramckrijte.workmanager.BackgroundWorker$doWork$1.run(BackgroundWorker.kt:71)
E/AndroidRuntime(28568): at android.os.Handler.handleCallback(Handler.java:789)
E/AndroidRuntime(28568): at android.os.Handler.dispatchMessage(Handler.java:98)
E/AndroidRuntime(28568): at android.os.Looper.loop(Looper.java:164)
E/AndroidRuntime(28568): at android.app.ActivityThread.main(ActivityThread.java:6944)
E/AndroidRuntime(28568): at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime(28568): at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
E/AndroidRuntime(28568): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

I want to detect phone state in android using while running in background.
I could make periodic task execute every 15 min. But I would like to listen to phone state as and when it changes and then call dart code. Below is screenshot of code running at 15 min interval.

Build failed with error

'pngData()' has been renamed to 'UIImagePNGRepresentation(_:)'
``` in swift 4.2

I've been trying to use the package, but I couldn't find out where to put the code to perform the desired Task. As I understood from the working example and from the plugin implementation, I would have to write a custom class that extends the Worker and override the doWork function, but when installing the package by pubspec I wasn't able to find out where to put it.

For apps supporting iOS 13 and higher use BGAppRefreshTask.

Check apple documentation.

My project uses Java codebase and the setup is only showing Kotlin code, do I need to change my codebase or can I adapt the setup for Java code?

I can't get to run ths library
this is how I configured my App class "App.java"

import io.flutter.app.FlutterApplication;
import io.flutter.plugin.common.PluginRegistry;
import io.flutter.plugins.GeneratedPluginRegistrant;

public class App extends FlutterApplication implements PluginRegistry.PluginRegistrantCallback{
    @Override()
    public void onCreate() {
        super.onCreate();
        WorkmanagerPlugin.setPluginRegistrantCallback(this);
    }

    @Override()
    public void registerWith(PluginRegistry reg) {
        GeneratedPluginRegistrant.registerWith(reg);
    }
}

this the code I ran just like the readme

    Workmanager.initialize(
        callbackDispatcher, // The top level function, aka callbackDispatcher
        isInDebugMode:
            true // If enabled it will post a notification whenever the task is running. Handy for debugging tasks
        );
    Workmanager.registerOneOffTask("1", "simpleTask");

and this is the error I am getting

E/AndroidRuntime( 8906): FATAL EXCEPTION: main
E/AndroidRuntime( 8906): Process: com.tafeel.full.masar4, PID: 8906
E/AndroidRuntime( 8906): java.lang.NullPointerException: Attempt to invoke virtual method 'android.app.Application android.app.Activity.getApplication()' on a null object reference
E/AndroidRuntime( 8906): 	at com.github.adee42.keyboardvisibility.KeyboardVisibilityPlugin.registerWith(KeyboardVisibilityPlugin.java:107)
E/AndroidRuntime( 8906): 	at io.flutter.plugins.GeneratedPluginRegistrant.registerWith(GeneratedPluginRegistrant.java:33)
E/AndroidRuntime( 8906): 	at com.tafeel.masar_4_flutter.App.registerWith(App.java:20)
E/AndroidRuntime( 8906): 	at be.tramckrijte.workmanager.BackgroundWorker$doWork$1.run(BackgroundWorker.kt:71)
E/AndroidRuntime( 8906): 	at android.os.Handler.handleCallback(Handler.java:873)
E/AndroidRuntime( 8906): 	at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime( 8906): 	at android.os.Looper.loop(Looper.java:193)
E/AndroidRuntime( 8906): 	at android.app.ActivityThread.main(ActivityThread.java:6669)
E/AndroidRuntime( 8906): 	at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime( 8906): 	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
E/AndroidRuntime( 8906): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

Is there any way to wake up the application when the task running and the application is closed? I tried to used a navigator but there aren't any context to push on it.

iOSPerformFetch actually calls the Flutter callback with nill arguments.

This will cause Flutter to start the callbackDispatcher, but it will not go through the user provided switch case.

backgroundMethodChannel?.invokeMethod(BackgroundMethodChannel.methods.iOSPerformFetch.rawValue, arguments: nil, result: ...)

Instead should be

backgroundMethodChannel?.invokeMethod(BackgroundMethodChannel.methods.iOSPerformFetch.rawValue, arguments: BackgroundMethodChannel.methods.iOSPerformFetch.rawValue, result: ...)

We could use a better sample.
Ideas:

• Have a log file that keeps track of previous ran tasks.
• Completely different UI for either Android and iOS.
  • Android could expose all possible options in a sort of form.
  • iOS could only expose the log file, since there is zero customisability on iOS

Current Sample:

First of all, amazing plugin! Thanks for the great work.

I'm new to Flutter development and had some progress with using isolates and SendPort to communicate data between the isolate and main thread. Unfortunately I found out the hard way that isolates do not continue running when the app goes to the background and that's when I found your plugin.

However, I can't seem to figure out what would be the best method with communicating between the main thread (layout) and the background isolate. The situation would be contacting a server multiple times and sending a progress (0-100) to the main thread which shows a progress indicator. The user would be able to dismiss the progress view and check the progress later where it would continue the progress.
I solved this now with an isolate connected to a parent widget which keeps the SendPort connection always open. So if a child widget closes/changes that parent would still have the progress.

Any ideas how this would be possible in your plugin?

Thanks!

Themuzz

Android Jetpack automatically changes your interval to 15min or 900000

This should be documented here as well. People who are using this plugin will not necessarily know that this is the case. Although Jetpack prints out:

W/WM-WorkSpec(13916): Interval duration lesser than minimum allowed value; Changed to 900000

I think it should be documented somewhere as well.

I wonder how is possible to sync offline data with server like firebase does in background especially in iOS . with OneOffTask by network connected constraint we can do it easily in android but in iOS we have just fetch in background can we use that for this purpose? If not and If the iOS has restricted this, how the firebase does syncing in iOS

AndroidManifest.xml:

<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="br.art.code.xxx" 
    xmlns:tools="http://schemas.android.com/tools">
    <application tools:replace="android:label,android:icon,android:name" android:name=".App" android:label="xxx"
        android:icon="@mipmap/ic_launcher" android:roundIcon="@mipmap/icon_round" android:fullBackupContent="@xml/backup_rules">
        <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationBootReceiver">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED"></action>
            </intent-filter>
        </receiver>

        <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationReceiver" />

        <meta-data android:name="com.facebook.sdk.ApplicationId" android:value="@string/facebook_app_id"/>
        <meta-data android:name="com.google.android.gms.ads.APPLICATION_ID" android:value="ca-app-pub-xxx~xxx"/>

        <activity android:name="com.yalantis.ucrop.UCropActivity" android:screenOrientation="portrait" 
            android:theme="@style/Theme.AppCompat.Light.NoActionBar"/>

        <activity android:name="com.facebook.FacebookActivity" android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
            android:label="@string/app_name" />

        <activity android:name="com.facebook.CustomTabActivity" android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.VIEW" />
                <category android:name="android.intent.category.DEFAULT" />
                <category android:name="android.intent.category.BROWSABLE" />
                <data android:scheme="@string/fb_login_protocol_scheme" />
            </intent-filter>
        </activity>

        <activity android:name=".MainActivity" android:launchMode="singleTop" android:theme="@style/LaunchTheme" 
            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
            android:hardwareAccelerated="true" android:windowSoftInputMode="adjustResize">
            <meta-data android:name="io.flutter.app.android.SplashScreenUntilFirstFrame" android:value="true" />
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
    </application>

    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
</manifest>

App.kt as documentation suggests.

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• No issues found!

• Document new debug iOS notification
• Add Kymer to contributors

In the performFetchWithCompletionHandler a FlutterMethodChannel is created and strongly captured inside the setMethodCallHandler block, causing it to never be released. See memory usage here:

Currently in the setMethodCallHandler block of backgroundMethodChannel a UIBackgroundFetchResult is created using the flutter result Int like so:

UIBackgroundFetchResult(rawValue: UInt(fetchResult))

We shouldn't rely on the internal ordering of UIBackgroundFetchResult cases, as they could change with future iOS releases.

After add and set up the work manager plugin, I tested my app with a simple task:

And when the 10 seconds passed it throws an exception:

However, the task was triggered, but many times (this bug made me uninstall the app):

My pubspec.yml:

What should I do to solve this?

As mentioned in issue #57: the Workmanager plugin should work out of the box with ObjC-only projects. Currently you get the following error when running pod install:

Unable to determine Swift version for the following pods:
    - `workmanager` does not specify a Swift version and none of the targets (`Runner`) integrating it have the `SWIFT_VERSION` attribute set.
Please contact the author or set the `SWIFT_VERSION` attribute in at least one of the targets that integrate this pod.

Hello, thanks for the package.
I am trying to write data to Google's Firestore every x minutes let's say. I created App.kt and set it as android:name. And my main file is as the following:

void callbackDispatcher() {
  Workmanager.executeTask((backgroundTask) {
    Test.writeTestData();
    return Future.value(true);
  });
}

void main() {
  if (Platform.isAndroid) {
    Workmanager.initialize(
      callbackDispatcher, // The top level function, aka Flutter entry point
      isInDebugMode: true,
    );
    Workmanager.registerPeriodicTask("testSensor", "simplePeriodicTask", frequency: Duration(seconds: 10));
  }
  runApp(MyApp());
} 

And the error is:

Unhandled Exception: PlatformException(error, WorkManager is not initialized properly. You have explicitly disabled WorkManagerInitializer in your manifest, have not manually called WorkManager#initialize at this point, and your Application does not implement Configuration.Provider., null)

Cheers.