Does system broadcasts any intents during factory reset and system updates?

Question

how to find factory reset is called in android

Answer 1

Old topic but maybe will help someone.

There is not any official event which states that Factory Data Reset will be performed. However for Android <= 22 (Lollipop) there is unofficial (hidden in the code) broadcast intent android.intent.action.MASTER_CLEAR which is fired when External Storage will be formatted. If you click factory reset for Android Settings then MASTER_CLEAR intent is fired, in the result you can state that there will be factory reset.

Sample code:

// Class Member 
private BroadcastReceiver receiver;
.
.
.

// In some method, e.g. onCreate()
IntentFilter filter = new IntentFilter();
filter.addAction("android.intent.action.ACTION_SHUTDOWN");
filter.addAction("android.intent.action.MASTER_CLEAR");

receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(
                    Intent.ACTION_SHUTDOWN)) {
                Log.d(TAG, "SHUTDOWN")
            }

            if (intent.getAction().equals("android.intent.action.MASTER_CLEAR")) {
                Log.d(TAG, "FACTORY DATA RESET")
            }
        };

registerReceiver(receiver, filter);

If there will be factory reset then you will see MASTER_CLEAR action followed by SHUTDOWN action. I tested on Nexus 5 and Androids 4.4.4, 5.0, 6.0, 6.0.1 and works.