android requestWindowFeature(Window.FEATURE_PROGRESS) ERROR -

i trying put progress status on windows view causing me error each time run app

package example.asynctaskdemo;  import android.os.asynctask; import android.os.bundle; import android.support.v7.app.actionbaractivity; import android.view.menu; import android.view.menuitem; import android.view.window; import android.widget.arrayadapter; import android.widget.listview;  import java.util.arraylist;   public class asynctaskdemo extends actionbaractivity {     private listview mainlist;      private string[] texts = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "10",     "11", "12", "13", "14"};     @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         requestwindowfeature(window.feature_progress);         setcontentview(r.layout.activity_asynctaskdemo);         mainlist = (listview)findviewbyid(r.id.my_list);         mainlist.setadapter(new arrayadapter<string>(this, android.r.layout.simple_list_item_1, new arraylist<string>()));          new myasync().execute();     }      class myasync extends asynctask<void, string, void>{         private arrayadapter<string> adapter;         private int counter = 0;         @override         protected void onpreexecute() {             adapter = (arrayadapter<string>)mainlist.getadapter();             setprogressbarindeterminate(false);             setprogressbarvisibility(true);         }          @override         protected void doinbackground(void... params) {              for(string item: texts){                 publishprogress(item);                 try {                     thread.sleep(2000);                 } catch (interruptedexception e) {                     e.printstacktrace();                 }             }             return null;         }          @override         protected void onprogressupdate(string... values) {             adapter.add(values[0]);             counter++;             setprogress((int)(((double)counter/texts.length)*10000));         }          @override         protected void onpostexecute(void avoid) {             setprogressbarvisibility(false);             debug_it.s(asynctaskdemo.this, "task has run successfully");         }     }       @override     public boolean oncreateoptionsmenu(menu menu) {         // inflate menu; adds items action bar if present.         getmenuinflater().inflate(r.menu.menu_asynctaskdemo, menu);         return true;     }      @override     public boolean onoptionsitemselected(menuitem item) {         // handle action bar item clicks here. action bar         // automatically handle clicks on home/up button, long         // specify parent activity in androidmanifest.xml.         int id = item.getitemid();          //noinspection simplifiableifstatement         if (id == r.id.action_settings) {             return true;         }          return super.onoptionsitemselected(item);     } } 

error:

03-31 19:34:18.960    1058-1058/example.asynctaskdemo e/androidruntime﹕ fatal exception: main     process: example.asynctaskdemo, pid: 1058     java.lang.runtimeexception: unable start activity componentinfo{example.asynctaskdemo/example.asynctaskdemo.asynctaskdemo}: android.util.androidruntimeexception: requestfeature() must called before adding content             @ android.app.activitythread.performlaunchactivity(activitythread.java:2195)             @ android.app.activitythread.handlelaunchactivity(activitythread.java:2245)  

the compiler suggesting me use supportrequestwindowfeature(); need error , know difference between supportrequestwindowfeature() , requestwindowfeature();

use requestwindowfeature(window.feature_progress);

before super.oncreate(savedinstancestate);

it work. getting problem .