Получить состояние экрана (активно/заблокировано)

KeyguardManager keyguardManager = (KeyguardManager) getSystemService(Activity.KEYGUARD_SERVICE); 
KeyguardLock lock = keyguardManager.newKeyguardLock(KEYGUARD_SERVICE); 
lock.disableKeyguard();

public class MyBroadCastReciever extends BroadcastReceiver {
 
    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
            Log.i(TAG,"Screen went OFF");
        } else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
            Log.i(TAG,"Screen went ON");
        }
    }
}

BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver()
    {
        @Override
        public void onReceive(Context context, Intent intent)
        {
            
        }
    };

IntentFilter filter = new IntentFilter();
  filter.addAction("android.intent.action.SCREEN_OFF");
  filter.addAction("android.intent.action.SCREEN_ON");
     registerReceiver(mBroadcastRecever, filter);

  unregisterReceiver(mBroadcastReceiver);
   mBroadcastReceiver= null;

package com.example.avastscan.avastscan;
 
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.os.Bundle;
 
public class MainActivity extends Activity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        
        IntentFilter filter = new IntentFilter();
        filter.addAction("android.intent.action.SCREEN_OFF");
        filter.addAction("android.intent.action.SCREEN_ON");
        registerReceiver(mybroadcast, filter);
 
        finish();
    }
 
    @Override
    protected void onDestroy(){
        unregisterReceiver(mybroadcast);
        mybroadcast= null;
        super.onDestroy();
    }
 
 
    //Create broadcast object
    BroadcastReceiver mybroadcast = new BroadcastReceiver() {
        //When Event is published, onReceive method is called
        @Override
        public void onReceive(Context context, Intent intent) {
            // TODO Auto-generated method stub
            System.out.println("MyReceiver");
 
            if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
                System.out.println("Screen ON");
            }
            else if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
                System.out.println("Screen went OFF");
            }
 
        }
    };
}

public class MainActivity extends AppCompatActivity
{
    private static final String LOG_TAG = MainActivity.class.getSimpleName();
 
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction(Intent.ACTION_SCREEN_ON);
        intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
        registerReceiver(mBroadcastReceiver, intentFilter);
 
 
    }
 
    BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver()
    {
        @Override
        public void onReceive(Context context, Intent intent)
        {
 
            if(Intent.ACTION_SCREEN_OFF.equals(intent.getAction()))
            {
                Log.i(LOG_TAG, "screen is OFF");
            }
            else if(Intent.ACTION_SCREEN_ON.equals(intent.getAction()))
            {
                Log.i(LOG_TAG, "screen is ON");
 
            }
        }
    };
 
    @Override
    protected void onDestroy()
    {
        super.onDestroy();
        unregisterReceiver(mBroadcastReceiver);
    }
}