Android App端与PHP Web端的简单数据交互实现示例

前言

由于学校科技立项的项目需要实现Android App端与PHP Web端的简单数据交互的实现，当前场景是Web端使用的是MySql数据库，Apache服务器和PHP语言编写的。数据交互的简单理解就是Android能向服务端进行数据获取，同时也能进行数据提交。

实现流程

流程说明

1. Andorid Server端对MySql数据库进行简单的查询操作，并将查询数据结果转换为Json格式提供给Andorid利用OKhttp读取再解析Json展示到APP上；同时Andorid端利用OKhttp提交给Andorid Server端，由Server端对MySql数据库对提交数据的添加。
2. Apache Server端通过解析PHP源代码，对MySql数据库的增删查改显示在WebSite。

具体实现

Andorid Server

获取数据

get_all_found_items.php

<?php
header('Content-Type:text/html;charset=utf-8');/*设置php编码为utf-8*/
/*
 * Following code will list all the items
 */ 

// array for JSON response
$response = array(); 

// include db connect class
require_once __DIR__ . '/db_connect.php'; 

// connecting to db
$db = new DB_CONNECT(); 

// get all items from items table
$result = mysql_query("SELECT *FROM items WHERE type='1'") or die(mysql_error());
// check for empty result
if (mysql_num_rows($result) > 0) {
  // looping through all results
  // items node
  $response["items"] = array(); 

  while ($row = mysql_fetch_array($result)) {
    // temp user array
    $items = array();
    $items["what"] = $row["what"];
    $items["when"] = $row["when"];
    $items["where"] = $row["where"];
    $items["detail"] = $row["detail"];
    $items["posttime"] = $row["posttime"];
 $resultcontcat = mysql_query("SELECT *FROM guests") or die(mysql_error());
 while ($row1 = mysql_fetch_array($resultcontcat)) {
  if ($row1["id"] == $row["gid"]){
  $items["contact"] = $row1["contact"];
  }
  }
    // push single items into final response array
    array_push($response["items"], $items);
  }
  // success
  $response["success"] = 1; 

  // echoing JSON response
  echo json_encode($response,JSON_UNESCAPED_UNICODE);
} else {
  // no items found
  $response["success"] = 0;
  $response["message"] = "No items found"; 

  // echo JSON
  echo json_encode($response,JSON_UNESCAPED_UNICODE);
}
?>

如以上PHP代码可知通过require_once()函数包含db_connect.php文件，执行数据库配置文件。定义数组$response接收查询的数据结果，通过判断不同的情况赋值$response[“success”]，并返回到Web页面显示

PHP文件执行结果

JSON

 {
  "items": [
    {
      "what": "手表",
      "when": "2017-10-21 00:00:00",
      "where": "北区宿舍楼#504",
      "detail": "白色的手表，XX品牌",
      "posttime": "2017-10-21 13:03:09",
      "contact": "138123456"
    },
    {
      "what": "手机",
      "when": "2017-10-04 00:00:00",
      "where": "北区商店#111",
      "detail": "iphone6s,土豪金",
      "posttime": "2017-10-21 13:03:46",
      "contact": "137123456"
    },
    {
      "what": "电脑",
      "when": "2017-10-21 14:39:54",
      "where": "图书馆#203",
      "detail": "联想品牌笔记本",
      "posttime": "2017-10-21 17:08:14",
      "contact": "5670001"
    },
    {
      "what": "细说PHP",
      "when": "2017-09-21 13:03:46",
      "where": "南馆#403",
      "detail": "黑色封面，第二版《细说PHP》",
      "posttime": "2017-10-21 17:36:53",
      "contact": "63513641"
    }
  ],
  "success": 1
}

提交数据

create_found_items.php

<?php
header('Content-Type:text/html;charset=utf-8');/*设置php编码为utf-8*/
/*
 * Following code will create a new product row
 * All product details are read from HTTP GET Request
 */ 

// array for JSON response
$response = array(); 

// check for required fields
if (isset($_GET['what']) && isset($_GET['when']) && isset($_GET['where']) && isset($_GET['detail'])&& isset($_GET['contact'])) { 

  $what = $_GET['what'];
  $when = $_GET['when'];
  $where = $_GET['where'];
  $detail = $_GET['detail'];
  $contact = $_GET['contact']; 

  // include db connect class
  require_once __DIR__ . '/db_connect.php'; 

  // connecting to db
  $db = new DB_CONNECT(); 

  // mysql inserting a new row
 $result2 = mysql_query("INSERT INTO guests(contact) VALUES('$contact')");
 $gidresult = mysql_query("SELECT id FROM `guests` WHERE contact='$contact'");
 while ($row = mysql_fetch_array($gidresult)) {
  $gid=$row['id'];
 }
  $result1 = mysql_query("INSERT INTO items(`what`, `when`, `where`, `type` ,`gid`, `detail`) VALUES('$what', '$when', '$where', '1', '$gid', '$detail')");  

  // check if row inserted or not
  if ($result1 && $result2) {
    // successfully inserted into database
    $response["success"] = 1;
    $response["message"] = "Items successfully created."; 

    // echoing JSON response
  echo json_encode($response,JSON_UNESCAPED_UNICODE);
  } else {
    // failed to insert row
    $response["success"] = 0;
    $response["message"] = "Oops! An error occurred."; 

    // echoing JSON response
  echo json_encode($response,JSON_UNESCAPED_UNICODE);
  }
} else {
  // required field is missing
  $response["success"] = 0;
  $response["message"] = "Required field(s) is missing"; 

  // echoing JSON response
  echo json_encode($response,JSON_UNESCAPED_UNICODE);
}
?>

判断GET请求的参数是否都存在，把获取的GET请求参数作为数据INSERT TO MySQL数据库。判断INSERT执行过程赋值$response[“success”]对应相应的$response[“message”]，显示在Web页面。

执行结果

Andorid

获取数据

核心代码 queryLosts()函数

private void queryLosts() {
 losts.clear();
 new Thread(new Runnable() {

 @Override
 public void run() {
  // TODO Auto-generated method stub

     OkHttpClient okHttpClient = new OkHttpClient();
     String url = "http://webSite/androidapi/get_all_lost_items.php";
     Request request = new Request.Builder()
         .url(url)
         .build();
     Call call = okHttpClient.newCall(request);
     try {
       Response response = call.execute();
       String res = response.body().string();
       if (res != null && !res.trim().equals("")){
         JSONObject jsonObject = new JSONObject(res);
         if (jsonObject.getInt("success") == 1){
           JSONArray jsonArray = jsonObject.getJSONArray("items");
           for (int i = jsonArray.length() - 1;i >= 0;i--){
             JSONObject item = jsonArray.getJSONObject(i);
             String what = null;
             try {
               what = item.getString("what");
             }catch (Exception e){
             }
             String when = null;
             try{
               when = item.getString("when");
             }catch (Exception e){
             }
             String where = null;
             try{
               where = item.getString("where");
             }catch (Exception e){
             }
             String detail = null;
             try {
               detail = item.getString("detail");
             }catch (Exception e){
             }
             String contact = null;
             try {
               contact = item.getString("contact");
             }catch (Exception e){
             }
             Lost lost = new Lost();
             lost.setTitle(what);
             String des = "地点：" + (where == null?"":where) +"   "+"时间：" + (when == null?"":when)+"\r" + "   "+"描述：" + (detail == null?"":detail);
             lost.setDescribe(des);
             lost.setPhone(contact == null?"":contact);
             losts.add(lost);
           }
         }
       }
     } catch (Exception e) {
       e.printStackTrace();
       showErrorView(0);
     }
     if (losts == null || losts.size() == 0) {
     handler.sendEmptyMessage(1);
       return;
     }
     if (losts.size() > 0){
      handler.sendEmptyMessage(2);
     }
 }
 }).start();

利用Android网络框架OKhttp,OKhttp一个处理网络请求的开源项目,是安卓端最火热的轻量级框架.请求接口url地址，获取Json数据利用JSONObject对Json数据进行解析。

提交数据

核心代码 addLost()函数

public Handler handler = new Handler(){
 public void handleMessage(android.os.Message msg) {
 switch(msg.what){
  case 1:
  Toast.makeText(this,"提交成功",Toast.LENGTH_LONG).show();
  break;
  case 2:
  Toast.makeText(this,"提交失败",Toast.LENGTH_LONG).show();
  break;
 }
 }
};
private void addLost(){
 OkHttpClient okHttpClient = new OkHttpClient();
 String url ="http://website/androidapi/create_lost_items.php?what="+title+"&when="+time+"&where="+place+"&detail="+describe+"&contact="+photo+"";
 Request request = new Request.Builder()
  .url(url)
  .build();

 try{
 Response response = okHttpClient.newCall(request).execute();
 res = response.body().string();
 handler.sendEmptyMessage(1);
 }catch (Exception e)
 {
 e.printStackTrace();
 handler.sendEmptyMessage(2);
 }
}

同样利用Okhttp,GET方式提交参数，try-catch获取异常，通过返回值给出一定的提交结果提示。

代码测试

数据同步

Web端

Andorid端

数据提交

提交结果

结语

以上过程基本实现，项目基本上可以交差了。这个项目PHP部分主要是由自己在弄，也是边学边做。Android方面是另外一个同学主要负责，期间也求助过我实习时结交的朋友帮助。感谢所有付出与帮助的人。希望对大家的学习有所帮助，也希望大家多多支持我们。