fuse-backgroundservice

In this repo you find a library for managing background services in Fuse Android.

With that you can make fuse apps running in background for long running tasks, even when the app is completely killed. Its a perfect solution if you want to do things permanently in frequent time intervals. Think about sending data frequently to a server. Also useful when a special sensor event occurs, or if you dont want that a download breaks off.

It runs on a separate process, which makes it independent from any runtime happenings.

Support

• Android

Unfortunately it currently only works on live devices or the Android preview. No support for pc preview or iOS.

How to use

Most things have to be done inside foreign code and Uno.

Uno and Java

You can add your own written Java Code inside the onStartCommand method of the ServiceClass.java. Currently there is a small example, how that could look like.

You can pass data from JavaScript to Uno and from Uno to the Service. You can pass all through the intent.putExtra() like so

Service.uno

    [Foreign(Language.Java)]
    extern(Android) void StartServiceJ(string arg)
    @{
        if(!@{Service_status:Get()}) {
           Context context = com.fuse.Activity.getRootActivity();
           Intent intent = new Intent(context, ServiceClass.class);
           intent.putExtra("amount", arg);
           @{Service:Of(_this).SetReceiver(Java.Object):Call(intent)};
           ...

and receive it via intent.getExtras() inside the Service

ServiceClass.java

    try {
            resultReceiver = intent.getParcelableExtra(RECEIVER);
            if (intent !=null && intent.getExtras()!=null) {
                String value = intent.getExtras().getString("amount");
                msg_global = Integer.parseInt(value);
            }
        } catch(Exception e) {
        ...

If the Service is supposed to deliver back an event or some kind of result, you can easily create a new Bundle and put that back by using the ResultReceiver-object this way

ServiceClass.java

    ...
    } else {
            try {
                Bundle result = new Bundle();
                result.putString("result", "Youre done with all toasts! :) PS this comes from inside the Service");
                resultReceiver.send(100, result);
                ...

This throws the event on the Uno side

Service.uno

        ...
        intent.putExtra("AndroidServiceReceiver", new ResultReceiver((Handler) @{Handler:Get()}) {
            @Override
            protected void onReceiveResult(int code, Bundle data) {
                if(code == 100)
                @{Service:Of(_this).UpdateView(string):Call(data.getString("result"))};
            }
        });
        context.startService(intent);
    @}


    void UpdateView(string args) {
        Emit("onServiceChanged", args);
    }

Very easy stuff :)

Inside the ServiceClass.java you can control the service type with the return value of the onStartCommand method.

• Long running tasks have a return value of START_STICKY which is currently the case. The process runs as long until the user manually decides to terminate it.

• If you want the service to be terminated after the work is done you should give back START_NOT_STICKY.

Please have a look to the official Android Docs for more information...

JavaScript

Of course you can manage the complete Service appearance from JavaScript, where you can bind it into the UX part.

<JavaScript>
        var Service = require("Service");
        var Observable = require("FuseJS/Observable");

        var textinput = Observable("");
        var textoutput = Observable("");


        function startservice() {
            Service.start(textinput.value);
        }

        function stopservice() {
            Service.stop();
        }

        Service.on("onServiceChanged", function(arg) {
            textoutput.value = arg;
        });

        module.exports = {
            startservice : startservice,
            stopservice : stopservice,
            textinput : textinput,
            textoutput : textoutput
        };
    </JavaScript>

To Do's

• Add support to inject data while the service is running
• Support for iOS