ی راه حل درست 
کد پیاچپی:
import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;
public class AlphabetListDemo extends Activity {
//String of alphabets //
String alphabts = {"A","B","C","D","E","F","G","H","I","J","K","L"};
ListView L1, L2;
myAdapter myadp;
myAdapter2 myadp2;
String prod_arr = {};
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
L1 = (ListView)findViewById(R.id.list1);
L2 = (ListView)findViewById(R.id.list2);
myadp = new myAdapter(this,alphabts);
L2.setAdapter(myadp);
// initial populating //
setProducts(0);
L2.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
setProducts(arg2);
}
});
}
public void setProducts(int number){
prod_arr = new String[25];
// adding some dummy data //
for(int i = 0; i < 25 ; i++){
prod_arr[i] = "Product : " + alphabts[number] + i;
}
//setting the adapter in listview //
myadp2 = new myAdapter2(AlphabetListDemo.this,prod_arr);
L1.setAdapter(myadp2);
}
class myAdapter extends ArrayAdapter<String>
{
TextView label;
ImageView image;
View row;
public myAdapter(Context context,String arr)
{
super(context, android.R.layout.simple_list_item_1, arr);
}
public View getView(final int position, View convertView, ViewGroup parent)
{
try{
LayoutInflater inflater=getLayoutInflater();
row = inflater.inflate(R.layout.lv_rows, parent, false);
label = (TextView)row.findViewById(R.id.item_title);
label.setText(alphabts[position]);
label.setTextColor(Color.YELLOW);
}catch(Exception e){
}
return row;
}
}
// adapter for second list.....
class myAdapter2 extends ArrayAdapter<String>
{
TextView label;
ImageView image;
View row;
public myAdapter2(Context context,String arr)
{
super(context, android.R.layout.simple_list_item_1, arr);
}
public View getView(final int position, View convertView, ViewGroup parent)
{
try{
LayoutInflater inflater=getLayoutInflater();
row = inflater.inflate(R.layout.lv_rows, parent, false);
label = (TextView)row.findViewById(R.id.item_title);
label.setText(prod_arr[position]);
label.setTextColor(Color.WHITE);
}catch(Exception e){
}
return row;
}
}
}
