どのようにPreferenceFragment ..のアクションバーで戻るボタンを設定しましたか？

Question

------------------------------------------------ ---------- Xmlコード------------------------------------- -----------------------

<?xml version="1.0" encoding="utf-8"?> 
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"> 
<PreferenceCategory android:title="Notification Settings"> 
    <SwitchPreference 
     android:defaultValue="true" 
     android:key="notification_state" 
     android:summary="Notification is Enabled" 
     android:title="Show Notification" /> 
    <Preference 
     android:key="reset_data" 
     android:summary="All data will be removed" 
     android:title="Reset Data" /> 
</PreferenceCategory> 
</PreferenceScreen> 

-------------------- ------------------------------------- Javaコード----------- -------------------------------------------------

あなたはonCreatにコード

ActionBar actionBar = getSupportActionBar(); 
     actionBar.setDisplayHomeAsUpEnabled(true); 

に従うことによって、戻るボタンを使用可能に設定している

import android.content.DialogInterface; 
import android.content.DialogInterface.OnClickListener; 
import android.content.SharedPreferences; 
import android.content.SharedPreferences.Editor; 
import android.os.Bundle; 
import android.preference.Preference; 
import android.preference.Preference.OnPreferenceChangeListener; 
import android.preference.Preference.OnPreferenceClickListener; 
import android.preference.PreferenceManager; 
import android.support.v4.app.NavUtils; 
import android.support.v7.app.AlertDialog; 
import android.view.MenuItem; 
import android.widget.Toast; 

import com.internet.services.DataService; 
import com.github.machinarius.preferencefragment.PreferenceFragment; 


public class SettingsActivity extends PreferenceFragment { 
    SharedPreferences dataPref; 

    public void onStart() { 
     super.onStart(); 
     dataPref = PreferenceManager.getDefaultSharedPreferences(getActivity()); 
    } 


    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     addPreferencesFromResource(R.xml.preferences); 

     findPreference("notification_state").setOnPreferenceChangeListener(new OnPreferenceChangeListener() { 
      @Override 
      public boolean onPreferenceChange(Preference preference, Object newValue) { 
       boolean isNotificationOn = (Boolean) newValue; 
       Editor edit = dataPref.edit(); 
       edit.putBoolean("notification_state", isNotificationOn); 
       edit.apply(); 
       if (isNotificationOn) { 
        findPreference("notification_state").setSummary("Notification is Enabled"); 
       } else { 
        findPreference("notification_state").setSummary("Notification is Disabled"); 
       } 
       return true; 
      } 
     }); 
     findPreference("reset_data").setOnPreferenceClickListener(new OnPreferenceClickListener() { 
      @Override 
      public boolean onPreferenceClick(Preference preference) { 
       AlertDialog.Builder builder = new AlertDialog.Builder(getActivity()); 
       builder.setMessage("All Data Will Be Clear!").setCancelable(false).setPositiveButton("Yes", new OnClickListener() { 
        @Override 
        public void onClick(DialogInterface dialog, int which) { 
         SharedPreferences sp_today = getActivity().getSharedPreferences(DataService.TODAY_DATA, 0); 
         SharedPreferences sp_month = getActivity().getSharedPreferences(DataService.MONTH_DATA, 0); 
         Editor editor = sp_today.edit(); 
         Editor edito2 = sp_month.edit(); 
         editor.clear(); 
         edito2.clear(); 
         editor.apply(); 
         edito2.apply(); 
         Toast.makeText(getActivity(), "Data Removed", Toast.LENGTH_LONG).show(); 
        } 
       }).setNegativeButton("No", new OnClickListener() { 
        @Override 
        public void onClick(DialogInterface dialog, int which) { 
         dialog.cancel(); 
        } 
       }); 
       AlertDialog alert = builder.create(); 
       alert.setTitle("Do You Want To Reset Data?"); 
       alert.show(); 
       return true; 
      } 
     }); 
    } 

    public boolean onOptionsItemSelected(MenuItem item) { 
     switch (item.getItemId()) { 
      case 16908332: 
       NavUtils.navigateUpFromSameTask(getActivity()); 
       return true; 
      default: 
       return super.onOptionsItemSelected(item); 
     } 
    } 


} 

Answer 1

e（）メソッドとその次のコードをクリックすると何が表示されるのですか？

@Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     int id = item.getItemId(); 
     if (id == android.R.id.home) { 
      finish(); 
     } 
     return super.onOptionsItemSelected(item); 
    }