Android 学习笔记之 Actionbar作为回到上一级

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.settings);
 
  isSendMsg = (Switch) findViewById(R.id.isSendMessage);
  isCall = (Switch) findViewById(R.id.isCall);
 
  data = (initDataApp)getApplication();
 
  isSendMsg.setChecked(data.isSendMsg());
  isCall.setChecked(data.isCall());
  ActionBar actionBar = getActionBar();
  actionBar.setDisplayHomeAsUpEnabled(true);
  //actionBar.setListNavigationCallbacks(adapter, callback);
 
 }

@Override
 public boolean onOptionsItemSelected(MenuItem item) {
  switch (item.getItemId()) {
  case android.R.id.home:
   //NavUtils.navigateUpFromSameTask(this);//onSaveInstanceState
   
    // This is called when the Home (Up) button is pressed
            // in the Action Bar.
   
            Intent parentActivityIntent = new Intent(this, MainActivity.class);
            parentActivityIntent.addFlags(
                    Intent.FLAG_ACTIVITY_CLEAR_TOP |
                    Intent.FLAG_ACTIVITY_NEW_TASK);
            startActivity(parentActivityIntent);
           
            finish();
   
   
  // onBackPressed();
   return true;
  }
  return super.onOptionsItemSelected(item);
 }

 @Override
 public boolean onOptionsItemSelected(MenuItem item) {
  switch (item.getItemId()) {
  case android.R.id.home:
   onBackPressed();
   return true;
  }
  return super.onOptionsItemSelected(item);
 }