how can i replace keyguardmanager

Question

I have a problem about making lockscreen.

The developer site recommends to use one of this methods

1. Method:

   private void setFlag(){
       getWindow().addFlags(
           WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD |
           WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
   }
   

2. Method (it is deprecated)

   private void disableLock() {
       private KeyguardManager km = null;
       private KeyguardManager.KeyguardLock keyLock = null;
       if (km == null) 
           km = ((KeyguardManager) getSystemService("keyguard"));
       if (keyLock == null) 
           keyLock = km.newKeyguardLock("keyguard");
       keyLock.disableKeyguard();
   }
   

When I used 1. method, when screen turn on by power button it goes off again immediately (Editor: Tried my best to understand it, not sure I got it right).

When I used 1. and 2. method there is no problem!

I want to replace this method

keyLock = km.newKeyguardLock("keyguard");

is there any way to replace this method?

Thank you so much for you to read the post :)