call webservice and show data on listview

send request format {"method":"item_list","parameter":{"category_id":"1"}} i want to pass json on btn_choose_menu click

package com.example.pattipizza;

import android.os.Bundle; import android.view.View;enter code here import android.view.View.OnClickListener; import android.widget.Button;

public class OrderSelect extends MainActivity {

Button btn_choose_menu, btn_send_order;

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.varified_activity);
    btn_choose_menu = (Button) findViewById(R.id.button1);

    btn_choose_menu.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub

        }
    });
    btn_send_order.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

        }
    });

}

}