Question

I have an Android Activity that needs to catch two different broadcasts. My current approach is to have a single BroadcastReceiver within the Activity and catch both the broadcasts with it:

public class MyActivity extends Activity {
    private MyActivity.BroadcastListener mBroadcastListener;
    private boolean mIsActivityPaused = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mylayout);

        // Create the broadcast listener and register the filters
        mIsActivityPaused = false;
        mBroadcastListener = new BroadcastListener();

        IntentFilter filter = new IntentFilter();
        filter.addAction(Params.INTENT_REFRESH);
        filter.addAction(Params.INTENT_UPDATE);
        registerReceiver(mBroadcastListener, filter);
    }

    @Override
    protected void onResume() {
        super.onResume();
        mIsActivityPaused = false;
    }

    @Override
    protected void onPause() {
        super.onPause();
        mIsActivityPaused = true;
    }

    @Override
    protected void onDestroy() {
        unregisterReceiver(mBroadcastListener);
        super.onDestroy();
    }

    private void refresh() {
        // refresh
    }

    private void update() {
        // update
    }

    private class BroadcastListener extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(Params.INTENT_REFRESH && !mIsActivityPaused)) {
                refresh();
            } else if (intent.getAction().equals(Params.INTENT_UPDATE)) {
                update();
            }
        }
    }
}

I want to execute refresh() only if my Activity is visible on the screen, but I want to catch INTENT_UPDATE and execute update() during the entire lifetime of the Activity, regardless of whether the Activity is visible or not.

I didn’t find any way to unregister only one of the two filters that I register in onCreate, so I use a flag to enable or disable the action to be executed when the INTENT_REFRESH broadcast is caught, depending on the state of the Activity.

The question is: is this the correct approach?

Or, would it be better to have two separate BroadcastReceivers as follows:

public class MyActivity extends Activity {
    private MyActivity.BroadcastListenerRefresh mBroadcastListenerRefresh;
    private MyActivity.BroadcastListenerUpdate mBroadcastListenerUpdate;
    private boolean mIsBroadcastListenerRefreshRegistered = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // Create the broadcast listeners
        mBroadcastListenerRefresh = new BroadcastListenerRefresh();
        mBroadcastListenerUpdate = new BroadcastListenerUpdate();

        registerReceiver(mBroadcastListenerRefresh, new IntentFilter(Params.INTENT_REFRESH));
        registerReceiver(mBroadcastListenerUpdate, new IntentFilter(Params.INTENT_UPDATE));
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (mBroadcastListenerRefresh != null && !mIsBroadcastListenerRefreshRegistered) {
            registerReceiver(mBroadcastListenerRefresh, new IntentFilter(Params.INTENT_REFRESH));
            mIsBroadcastListenerRefreshRegistered = true;
        }
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (mBroadcastListenerRefresh != null && mIsBroadcastListenerRefreshRegistered) {
            unregisterReceiver(mBroadcastListenerRefresh);
            mIsBroadcastListenerRefreshRegistered = false;
        }
    }

    @Override
    protected void onDestroy() {
        unregisterReceiver(mBroadcastListenerRefresh);
        unregisterReceiver(mBroadcastListenerUpdate);
        super.onDestroy();
    }

    private void refresh() {
        // refresh
    }

    private void update() {
        // update
    }

    private class BroadcastListenerRefresh extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(Params.INTENT_REFRESH)) {
                refresh();
            }
        }
    }

    private class BroadcastListenerUpdate extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(Params.INTENT_UPDATE)) {
                update();
            }
        }
    }
}

And which one has better performance?

Answer 1

instead, you may provide two different intent filters:

filter for refresh only

IntentFilter filterRefresh = new IntentFilter(Params.INTENT_REFRESH);

filter for refresh and update

IntentFilter filterRefreshUpdate = new IntentFilter();
filterRefreshUpdate.addAction(Params.INTENT_REFRESH);
filterRefreshUpdate.addAction(Params.INTENT_UPDATE);

now you may switch between intent filters by registering and un-registering the desired one but your receiver’s implementation would be same