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我想在我的应用程序的phpmyadmin显示数据库中的用户名的列表，但我不断收到以下数据没有被显示在列表视图我从数据库
Unable to start activity ComponentInfo{ie.example.artur.adminapp/ie.example.artur.adminapp.ShowUsers}: java.lang.NullPointerException: storage == null
我明白这意味着数据没有被发送，因此选择时活动无法启动，列表为空，但是我的问题为什么列表中没有填充数据？
这是我ShowUser活动
package ie.example.artur.adminapp;
import android.content.Intent;
import android.os.Bundle;
import android.os.StrictMode;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toolbar;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.List;
import static android.R.attr.name;
/**
* Created by family on 24/07/2017.
*/
public class ShowUsers extends AppCompatActivity {
ListView lv;
//String[] names = {"Amy","John","Joseph","Carl"};
InputStream is = null;
String line= null;
String result = null;
String temp="";
String[] arr;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.showusers);
lv = (ListView) findViewById(R.id.lv);
//Inlfate the list view with the items
lv.setAdapter(new ArrayAdapter<String>(ShowUsers.this,android.R.layout.simple_list_item_1,arr));
android.widget.Toolbar toolbar = (android.widget.Toolbar) findViewById(R.id.toolbar);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
//set up the code to fetch data from the database
try {
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("http://10.3.2.51/www/");
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
//SETUP THE INPUTSTREAM TO RECEIVE THE DATA (INITIAL)
}catch (Exception e){
System.out.println("Exception 1 caught");
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
// Create a String builder object to hold the data
StringBuilder sb = new StringBuilder();
while((line = reader.readLine())!=null)
sb.append(line+"\n");
//Use the toString() method to get the data in the result
result = sb.toString();
is.close();
//check the data by printing the results in the logcat
System.out.println("-----Here is my data -----");
System.out.println(result);
}catch(Exception e){
System.out.print("Exception 2 caught");
}
try{
JSONArray jsonArray = new JSONArray(result);//Create a json array
int count = jsonArray.length();
for(int i=0; i<count; i++){
//create a json object to extract the data
JSONObject json_data = jsonArray.getJSONObject(i);
temp +=json_data.getString("name")+":";
//where name is attribute of the getdata table
//using ':' as the delimiter
}
//Afer receiving everything store the contents in a string array from temo separated using the delimiter
arr = temp.split(":");
//set the list adapter with the array arr
lv.setAdapter(new ArrayAdapter<String>(ShowUsers.this,android.R.layout.simple_list_item_1, arr));
}catch(Exception e){
System.out.println("I am really bored of writing all these exception blocks");
}
}
public boolean onCreateOptionsMenu(Menu menu)
{
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
{
switch (item.getItemId())
{
case R.id.action_settings : startActivity (new Intent(this, ShowUsers.class));
break;
}
return super.onOptionsItemSelected(item);
}}
}
这是从数据库中的表用户在phpMyAdmin：
而且这个地方我有我的tut.php文件保存： 
tut.php：
<?php
$con=mysql_connect("localhost","root","");
mysql_select_db("socialmedia_website",$con);
$r=mysql_query("select name from users where 1";
while($row=mysql_fetch_array($r))
{
$out[]=$row;
}
print(json_encode($out));
mysql_close($con)
*此外，我正在使用Android设备做这个项目
这是我收到回： 
不使用mysql_ *。只使用mysqli_ * –
** mysql **已被弃用，并在PHP 7中完全删除。使用** mysqli **或** PDO **代替 –
@ B.Desai是的，我知道我只是没有意识到，因为我正在关注视频教程 – Lucy