Question

I have a service which periodically downloads some updates from a web site.
Default period is long, about 10 mins and I do that with an AlarmManager which starts this service.

Network can be on or off, in case it’s off service should download news as soon as network returns on, because interval is long and, in the worst case, you could have to wait 20 min till next update.

I made a network state broadcast receiver, and, with little code I made a NetworkListener interface:

public interface NetworkStateListener {
public void onNetworkOn();
public void onNetworkDown();
}

So my service has these 2 methods and can know when network goes on or off.

My idea is the following: in the onStart() method I spawn a new thread: if network is off thread waits, otherwise downloads. When onNetworkOn() is called I call a notify():

private boolean threadWaiting; //a flag so that I don't spawn multiple threads
public int onStartCommand(Intent intent, int flags, int startId) {
    if(!threadWaiting){//if already a thread waiting do nothing and exit
        Thread t = new Thread(new Runnable(){

            @Override
            public void run() {
                synchronized(binder){
                    while(!isNetworkOn())
                        try {
                            threadWaiting = true;
                            binder.wait();
                        }catch(InterruptedException ex){
                            ex.printStackTrace();
                        }
                }
                // blocks until network connection is available
               threadWaiting = false;
               //... operations ...

And this is onNetworkOn() method:

public void onNetworkOn() {
    synchronized(binder){
        binder.notify();
    }

is this the right way to proceed?

Answer 1

Solved:
I keep a boolean flag “missed update in my service”:

boolean missedUpdate = false;

then in my onStartCommand:

if(isNetworkOn()){
    //do actual code
}else
    missedUpdate = true;

while in my on network on:

public void onNetworkOn(){
    if(missedUpdate){
       //download updated news
       // reset timer
       missedUpdate = false;
    }
}