Accessing object creating in Activity/Fragment from a receiver

Issue

This is probably not feasible, but I have a WearOS app that has downloading functionality. According to the documentation, I can request a high-bandwidth network:

https://developer.android.com/training/wearables/data/network-access#requesting-wifi-connectivity

I have all this working however, I also need to release the network when downloading is complete:

Once onAvailable() is called, the device will attempt to remain connected to the Wi-Fi network until the NetworkCallback is released. Release the callback when you no longer need a Wi-Fi network to preserve battery life.

I can release the callback in the Activity/Fragment but I need the connection to stay open until the all downloads are complete. I have a receiver where I check if there are no longer any downloads but, obviously, can't release the callback there.

I thought about using a Singleton but not sure how to create a Singleton for a callback

Solution

If you are register receiver from activity,you can create in this receiver interface,and during creation of receiver you can set to receiver your listener,which you will create in activity/fragment. For example:

class someReceiver extends BroadcastReceiver {
interface OnLoadComplitionListener {
void allLoadsCompleted();
}
private OnLoadComplitionListener listener;
public void setOnLoadComplitionListener(OnLoadComplitionListener listener) {
this.listener =listener;
}
@override
public void OnReceive(Context context) {
listener.allLoadsCompleted();
}
}

And in your activity before registration of your receiver you should set someReceiver.OnLoadComplitionListener and override method allLoadsCompleted(). Name of classes was wrote inexact.

Answered By - alexandr kozlovskiy