[Android] ListView มีปัญหาค่ะ เข้าหน้าที่แสดง Listview ไม่ได้เลย ไม่รู้ว่าผิดตรงไหน ช่วยดูด้วยนะคะ

package com.BT.buytrash;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.TextView;

public class price extends Activity{

	private EditText search;
	private ImageButton type_iron;
	private ImageButton type_plastic;
	private ImageButton type_paper;
	private ImageButton type_kew;
	private ImageButton type_loha;
	private ImageButton type_fifa;
	private ImageButton type_other;
	private ListView listview_product;
	private TextView test;
	//private String[][]	data_listview;
	private ArrayList<String>  data_listview;
	 
	
	String url = "http://10.0.2.2/BuyTrash/price_product.php";
	List<NameValuePair> params = new ArrayList<NameValuePair>(); 

	
	//----------------------------------------------------------------
	
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.price);
		
		search = (EditText) findViewById(R.id.EditText_search);
		type_iron = (ImageButton) findViewById(R.id.Button_type_iron);
		type_plastic = (ImageButton) findViewById(R.id.Button_type_plastic);
		type_paper = (ImageButton) findViewById(R.id.Button_type_paper);
		type_kew = (ImageButton) findViewById(R.id.Button_type_kew);
		type_loha = (ImageButton) findViewById(R.id.Button_type_loha);
		type_fifa = (ImageButton) findViewById(R.id.Button_type_fifa);
		type_other = (ImageButton) findViewById(R.id.Button_type_other);
		listview_product = (ListView) findViewById(R.id.listview_price);
		
		params.add(new BasicNameValuePair("keyword", search.getText().toString()));
		
		test = (TextView) findViewById(R.id.textViewtest);
		
		
		ArrayList<HashMap<String, String>> re = new ArrayList<HashMap<String, String>>();   ;
	
		re = getHttpPost(url,params);
		
		String a = "id = " + re.get(0).get("p_id").toString() +
				"p_name = " + re.get(0).get("p_name").toString() +
		"p_type = " + re.get(0).get("p_type").toString() + 
		"p_price1 =" + re.get(0).get("p_price1").toString() + 
		"p_price2 = " + re.get(0).get("p_price2").toString() + 
		"p_price3 = " + re.get(0).get("p_price3").toString() +
		 "p_sale = " + re.get(0).get("p_sale").toString()+"size = "+re.size(); 
		test.setText(a);
//------------------------------------------------------------

		 // Adapter
	 		listview_product.setAdapter(new MyAdapters());
	 		
	 		data_listview = new ArrayList<String>();
			data_listview.add("ราคาซื้อและราคาขายสินค้า");  	// 0
			data_listview.add("ซื้อสินค้า");				// 1
	        data_listview.add("ข้อมูลลูกค้า");		
	/* 		
	 		data_listview = new String[re.size()][7];
			
		for(int i=0 ; i< re.size() ; i++){			
			data_listview[i][0] = re.get(i).get("p_id").toString(); 
			data_listview[i][1] = re.get(i).get("p_name").toString(); 
			data_listview[i][2] = re.get(i).get("p_type").toString(); 
			data_listview[i][3] = re.get(i).get("p_price1").toString(); 
			data_listview[i][4] = re.get(i).get("p_price2").toString(); 
			data_listview[i][5] = re.get(i).get("p_price3").toString(); 
			data_listview[i][6] = re.get(i).get("p_sale").toString();			
		}
		*/
		
	}
	//-------------------------------------------------------------------------------------
	
	private class MyAdapters extends BaseAdapter{
		
		private Holder holder;
		
		public int getCount() {
			
			return data_listview.size();
		}

		public Object getItem(int position) {

			return null;
		}

		public long getItemId(int position) {

			return 0;
		}

		public View getView(int position, View view, ViewGroup parent) {
			if( view == null){
				view = LayoutInflater.from(getApplicationContext()).inflate(R.layout.list_price_item, null);
				holder = new Holder();
				holder.p_name = (TextView) view.findViewById(R.id.product_name);
				holder.p_price1 = (TextView) view.findViewById(R.id.price1);
				holder.p_price2 = (TextView) view.findViewById(R.id.price2);
				holder.p_price3 = (TextView) view.findViewById(R.id.price3);
				holder.p_sale = (TextView) view.findViewById(R.id.price_sale);
				view.setTag(holder);
				
			}else{
				holder = (Holder) view.getTag();
			}
			
			
			holder.p_name.setText(data_listview.get(position));
			holder.p_price1.setText(data_listview.get(position));
			holder.p_price2.setText(data_listview.get(position));
			holder.p_price3.setText(data_listview.get(position));
			holder.p_sale.setText(data_listview.get(position));
			
			return view;
		}
		private class Holder{   //จะบอกว่า view แต่ละรายการมีอะไรบ้าง
			public TextView p_name;
			public TextView p_price1;
			public TextView p_price2;
			public TextView p_price3;
			public TextView p_sale;
			
		}
		
	}
	   
	  //----------------------------------------------------------------------------------------
	    
	  	public ArrayList<HashMap<String, String>> getHttpPost(String url, List<NameValuePair> params) {
//	public ArrayList<String> getHttpPost(String url, List<NameValuePair> params) {
	  		
	  		ArrayList<HashMap<String, String>> myArrList = new ArrayList<HashMap<String, String>>(); 
	  		  //String[][] re ;
	  		  InputStream is = null;
	  		  String result = "";
	  		  ArrayList<String> name  = new ArrayList<String>(); 
	  		 // -------------------------------connect----------------------------------------------------
	 		 try {  
	 			      
	 			 HttpClient client = new DefaultHttpClient();       
	 			 HttpPost httpPost = new HttpPost(url); 
	 		
	 // -------------------------------set  UTF8 --------------------------------------------------
	 		
	 			 httpPost.setEntity(new UrlEncodedFormEntity(params,"UTF-8"));
	 			 HttpResponse response = client.execute(httpPost);
	 			 HttpEntity entity = response.getEntity();
	 			 is = entity.getContent();
	 			 
	 		  }catch (Exception e) {
	 			  Log.e("log_tag", "Error in http connection " + e.toString());
	 		  }

	 // -------------------------------to String --------------------------------------------------
	 		 
	 		 try {
	 			   BufferedReader reader   	=  	new BufferedReader(new InputStreamReader(is, "iso-8859-11"), 8);
	 			   StringBuilder  sb 		= 	new StringBuilder();	
	 			   String 		  line 		= 	null;
	 			   while ((line = reader.readLine()) != null) {
	 			    sb.append(line + "\n");   
	 			   }
	 			   is.close();
	 			   result = sb.toString();
	 			  
	 		 } catch (Exception e) {
	 			   Log.e("log_tag", "Error converting result " + e.toString());
	 		 }
	 		 
	 // -------------------------------JSON to JAVA --------------------------------------------------
			   
			 
	 		 try {
	 			   JSONArray jArray = new JSONArray(result);
	 			   //re = new String[jArray.length()][7]; 
	 			  
	 			  
	 			  HashMap<String, String> map; 
	 			 
	 			  
	 			for (int i = 0; i < jArray.length(); i++) {
	 			 JSONObject json_data = jArray.getJSONObject(i);  
	 				
	 			 map = new HashMap<String, String>(); 
	 			 	   
	 			 	   map.put("p_id",json_data.getString("p_id") );      
	 			 	   map.put("p_name", json_data.getString("p_name") );       
	 			 	   map.put("p_type", json_data.getString("p_type") );     
	 			 	   map.put("p_price1", json_data.getString("p_price1") ); 
	 				   map.put("p_price2", json_data.getString("p_price2") ); 
	 				   map.put("p_price3", json_data.getString("p_price3") ); 
	 				   map.put("p_sale", json_data.getString("p_sale") ); 
	 		   myArrList.add(map); 
						
	 				  

	 			 }
	 			   
	 		  } catch (JSONException e) {
	 			   Log.e("log_tag", "Error parsing data " + e.toString());
	 		  }
	 		
	 		  return myArrList;
	 		// return name;
	 	}
	  	
	    @Override
	    public boolean onCreateOptionsMenu(Menu menu) {
	        getMenuInflater().inflate(R.menu.login, menu);
	        return true;
	    }
	
	  	
}