Setting up the code implementation of Android device WIFI forever open when sleeping

package ;

import ;
import ;
import ;
/**
  * Demo description:
  * Set the device to always keep WLAN on during sleep.
  *
  * References:
  * 1 /questions/8652031/how-to-modify-wi-fi-sleep-policy-programmatically/8655070#8655070
  * 2 /mrlixirong/article/details/24938637
  * Thank you very much
  *
  * Notes:
  * 1.WIFI_SLEEP_POLICY is used here
  * Instead of .WIFI_SLEEP_POLICY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  *
  * 2 Permission <uses-permission android:name=".WRITE_SETTINGS"/>
  *
  * 3 In actual projects, it is a bit rude to set up WIFI so compulsively to keep on opening when sleeping.
  * You can first record the original WIFI strategy and restore it after our logic is completed.
  */
public class MainActivity extends Activity {

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  (savedInstanceState);
  setContentView();
  setWifiNeverSleep();
 }

 private void setWifiNeverSleep(){
  int wifiSleepPolicy=0;
  wifiSleepPolicy=(getContentResolver(),
                    .WIFI_SLEEP_POLICY,
                    .WIFI_SLEEP_POLICY_DEFAULT);
  ("---&gt; Before modificationWifiSleep policy value WIFI_SLEEP_POLICY="+wifiSleepPolicy);
  
  
  (getContentResolver(),
            .WIFI_SLEEP_POLICY,
            .WIFI_SLEEP_POLICY_NEVER);
  
  
  wifiSleepPolicy=(getContentResolver(),
        .WIFI_SLEEP_POLICY,
        .WIFI_SLEEP_POLICY_DEFAULT);
    ("---&gt; ModifiedWifiSleep policy value WIFI_SLEEP_POLICY="+wifiSleepPolicy);
 }
 
}
&lt;RelativeLayout xmlns:andro
 xmlns:tools="/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 &gt;

 &lt;TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@string/hello_world" /&gt;

&lt;/RelativeLayout&gt;