How to select text from Navigation Spinner on ActionBar in Android?

I have Navigation Spinner on my Activity's ActionBar. It was populated by data from SQLite Database using SimpleCursorAdapter. I have done this using following code

String query="select rowid _id, vehicleName from vehiclesTable";
    try{
        Cursor c1=db.rawQuery(query,null);
        if (c1.getCount()>0){
         while (c1.moveToNext()){
             adapter=new SimpleCursorAdapter(this,android.R.layout.simple_list_item_1, c1,new String[]{"vehicleName"},new int[]{android.R.id.text1});
         }
        }
    }catch (SQLiteException e){
        Toast.makeText(MainPage.this,e.toString(),Toast.LENGTH_SHORT).show();
    }

    actionBar=getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST);
    actionBar.setListNavigationCallbacks(adapter,this);

Now I have to get the selected items text and display it in Toast. I don't know how to do that. Anyone who knows please help me with it.