要实现在锁屏状态下点击通知显示应用程序活动及解锁手机，需要进行以下步骤：

1. 在AndroidManifest.xml文件中添加以下权限：

2. 在应用程序中创建一个服务（Service），该服务用于唤醒屏幕并解锁手机：

public class LockScreenService extends Service {

    private final IBinder mBinder = new LocalBinder();

    public class LocalBinder extends Binder {
        public LockScreenService getService() {
            return LockScreenService.this;
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        return mBinder;
    }

    public void unlockScreen() {
        KeyguardManager keyguardManager = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
        KeyguardManager.KeyguardLock keyguardLock = keyguardManager.newKeyguardLock("unlock");
        keyguardLock.disableKeyguard();

        PowerManager powerManager = (PowerManager) getSystemService(Context.POWER_SERVICE);
        PowerManager.WakeLock wakeLock = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK |
                PowerManager.ACQUIRE_CAUSES_WAKEUP |
                PowerManager.ON_AFTER_RELEASE, "wakeup!");
        wakeLock.acquire();
    }
}

3. 在BroadcastReceiver中接收通知，并处理点击事件：

public class NotificationReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        NotificationManager notificationManager =
                (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.cancelAll();

        //启动服务
        Intent serviceIntent = new Intent(context, LockScreenService.class);
        context.startService(serviceIntent);

        //启动活动
        Intent activityIntent = new Intent(context, MainActivity.class);
        activityIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK |
                Intent.FLAG_ACTIVITY_CLEAR_TOP |
                Intent.FLAG_ACTIVITY_SINGLE_TOP);
        context.startActivity(activityIntent);
    }
}

4. 在MainActivity中处理解锁屏幕事件：