How to save the instancestate of my activity

I obviously new and have been trying to two days to figure out how to save the state of my main activity to no avail. I would appreciate any help. When I launch the ShowDetail activity and return to the main activity I have no data in the list. I have two xml files a main.xml and a item.xml file. main is just a listview and a textview. Item.xml is 3 textviews for the data in the list. Item Here is the code from my main activity:

public class main extends ListActivity {

private EventsData events;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);        
    setContentView(R.layout.main);
    events = new EventsData(this);
    try {
     Cursor cursor = getEvents();
     showEvents(cursor);
    } finally {
     events.close();
    }
}

@Override
public void onSaveInstanceState(Bundle savedInstanceState){
 super.onSaveInstanceState(savedInstanceState);
}

@Override
public void onRestoreInstanceState(Bundle savedInstanceState){
 super.onRestoreInstanceState(savedInstanceState);
}

@Override
public void onPause(){
 super.onPause();
}

@Override
p开发者_开发问答ublic void onRestart(){

 super.onRestart();

}


private static String[] FROM = { CODE, EXCERPT, _ID, };
private static String ORDER_BY = CODE + " ASC";
private Cursor getEvents() {
 SQLiteDatabase db = events.getReadableDatabase();
 Cursor cursor = db.query(TABLE_NAME, FROM, null, null, null, null, ORDER_BY);
 startManagingCursor(cursor);
 return cursor;
}

private static int[] TO = { R.id.code, R.id.excerpt, };
private void showEvents(Cursor cursor) {
 SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, 
   R.layout.item, cursor, FROM, TO);
 setListAdapter(adapter);
}

private static String[] MIKEY = { _ID, CODE, DEFINITION };
protected void onListItemClick(ListView l, View v, int position, long id) {
 Cursor cursor = ((CursorAdapter)getListAdapter()).getCursor();
 cursor.getLong(2);

 SQLiteDatabase db = events.getReadableDatabase();
 Cursor c = db.query(TABLE_NAME, MIKEY, "_id = "+cursor.getLong(2)+"", null, null, null, null);
 c.moveToFirst();

 Intent in1  = new Intent();
 Bundle bun = new Bundle();
 bun.putLong("id", c.getLong(0));
 bun.putString("code", c.getString(1));
 bun.putString("definition", c.getString(2));
 in1.setClass(this, ShowDetail.class);
 in1.putExtras(bun);

 startActivity(in1);
}

}

I'd say you need to place your general actions into onResume() instead of in onCreate().

Maybe a look at the application lifecycle helps understanding what I mean: http://developer.android.com/reference/android/app/Activity.html