Simplest way to use / create a PendingIntent

问题:

Maybe there's something really simple that I don't see. I'm trying to call a method from some API, and this method asks for a PendingIntent to send me asynchronously some value. I've read the doc and examples for half an hour, and can't wrap my head around a simple way to do it.

More precisely, I want to call the ActivityRecognitionApi. To illustrate, here's how I receive the location from a similar api:

LocationServices.FusedLocationApi.requestLocationUpdates(
                            mGoogleApiClient, 
                            mLocationRequest,
                            new LocationListener() {
                                @Override
                                public void onLocationChanged(Location location) {

                                    // I can do something with the location

                                }
                            });

So I want to do the same to receive the recognized activity :

ActivityRecognition.ActivityRecognitionApi.requestActivityUpdates(mGoogleApiClient,
                            1000,
                            // ... what here ?);

So what would be the simple way to create a pendingIntent to just receive the value ? I tried to create an anonymous PendingIntent but the class is final. I don't want to start a Service, or Activity, or broadcast anything... Is there just a simple way to create this PendingIntent to execute just a block of code?

Thanks in advance,

回答1:

I don't want to start a Service, or Activity, or broadcast anything...

Then you cannot use ActivityRecognition.ActivityRecognitionApi.requestActivityUpdates().

Is there just a simple way to create this PendingIntent to execute just a block of code?

No.

The conventional use case for this API is to find out about changes in the device state over a period of time, and your process may not be running in between those changes of state. Hence, they optimized this API for the conventional use case, requiring a PendingIntent so they can get your app running again to tell you about the state change.

If you happen to be using this API to find out about state changes only while one magic activity of yours happens to be in the foreground, you can use createPendingResult() on that activity to get a PendingIntent that will invoke onActivityResult() on that same activity. However, this is a fairly niche scenario, particularly for this API.

Otherwise, you need to treat this no differently than if you were scheduling an alarm with AlarmManager or a job with JobScheduler:

• If the work that you are doing will take less than 1 millisecond, create a manifest-registered BroadcastReceiver and use a getReceiver() PendingIntent

• If the work that you are doing will take between 1 millisecond and 15 seconds, create an IntentService and use a getService() PendingIntent

• If the work that you are doing may take in excess of 15 seconds, create a manifest-registered WakefulBroadcastReceiver and an IntentService, use a getReceiver() PendingIntent, and have the WakefulBroadcastReceiver pass the work to the IntentService via startWakefulService().