How to actively request for scans

Question

How to actively request for scans?

The only way provided by the WifiManager API, as I understand it, is the startScan() method, which just starts a receiver to listen for the Wi-Fi service scans. The problem is the delay between scans, it takes too much time! If I do not move too much, no scans are received, and if I do, it takes too much time to notice.

Is there a way to dynamically request a scan?

This is the code I use:

    // ...
    wifi = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
    context.registerReceiver(this, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
    wifi.startScan();
}

// ...

@Override
public void onReceive(Context context, Intent intent)
{
    List<ScanResult> results = this.wifi.getScanResults();
    // ...

Edit:

If it isn't clear...

The onReceive method receives scans sometimes, but it takes too long. I want to trigger a scan, not just wait for it comes. It can be done in a thread, repeatedly making it scan, as @Barns suggested.

Answer 1

The preferred coding solution would incorporate a Handler with a postDelayed instead of Thread.sleep. It is important to remove any Callbacks!

Try something like this:

private boolean continueLoop = true;
private Handler myHandler = new Handler();

private void startAutoDownloadManager() {
    try{
        Log.d(TAG, "AutoDownloadManager - Started");
        // here the delay (in this example it is effectively the interval) is 1 second
        myHandler.postDelayed(mAutoDownloadManager, 1000);
    }
    catch(Exception ex){
        Log.e(TAG, ex.getMessage());
    }
}

private Runnable mAutoDownloadManager = new Runnable() {
    public void run() {
        if(continueLoop){
            // preform the scan
            this.wifi.startScan();

            //re-trigger the call to start the scan
            startAutoDownloadManager();
        {
    }
};

// Make certain that you remove the callback when you leave the activity -- maybe in onPause()
private void stopAutoDownloadManager(){
    try{
        myHandler.removeCallbacks(mAutoDownloadManager);
    }
    catch(Exception ex){
        Log.e(TAG, ex.getMessage());
    }
}