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Note that notifyDataSetChanged() function of the new ArrayAdapter have to be called after setListAdapter(), to re-draw the List on screen.
package com.exercise.AndroidDualListActivity;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class AndroidDualListActivity extends ListActivity{
String[] month = {
"January", "February", "March", "April",
"May", "June", "July", "August",
"September", "October", "November", "December"
};
String[] DayOfWeek = new String[] {
"Sunday", "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday", "Saturday"};
ArrayAdapter<String> monthAdapter, weekOfDayAdapter;
String strMonth, strDayOfWeek;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
monthAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, month);
weekOfDayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, DayOfWeek);
setListAdapter(monthAdapter);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
// TODO Auto-generated method stub
super.onListItemClick(l, v, position, id);
if(getListAdapter() == monthAdapter){
strMonth = (String)getListView().getItemAtPosition(position);
setListAdapter(weekOfDayAdapter);
weekOfDayAdapter.notifyDataSetChanged();
}else{
strDayOfWeek = (String)getListView().getItemAtPosition(position);
Toast.makeText(getBaseContext(), strMonth + ":" + strDayOfWeek, Toast.LENGTH_LONG).show();
setListAdapter(monthAdapter);
monthAdapter.notifyDataSetChanged();
}
}
}
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