做了个安卓和php端通信的app，但是返回数据处理时异常

最新推荐文章于 2022-02-25 11:43:49 发布

原创最新推荐文章于 2022-02-25 11:43:49 发布 · 601 阅读

CC 4.0 BY-SA版权

本文介绍了一个安卓应用与PHP服务器进行通信的案例。重点在于调试过程中遇到的问题：当服务器返回错误信息时，客户端无法正常处理。通过移除处理JSON数据的代码段，解决了条件判断不执行的问题。

做了个安卓和php端通信的app,  先post  id到php端检查许可，成功返回一个json格式的数组，失败返回Error。
运行时发现，当成功时能返回json数据，一旦失败app端完全没有反映，就是if语句完全不执行，连空的toast框都没有。

检查后发现，一旦删了下面红色部分的处理json数据的语句，  if和else语句都可以正确执行

new Thread(new Runnable() {
            public void run()
            {

                try {

                    client = new DefaultHttpClient();
                    StringBuilder builder = new StringBuilder();

                    ArrayList params = new ArrayList();
                    params.add(new BasicNameValuePair("id",id));

                    HttpPost myget = new HttpPost("http://192.168.210.51/login2.php");

                    myget.setEntity(new UrlEncodedFormEntity(params));
                    HttpResponse response = client.execute(myget);
                    HttpEntity entity = response.getEntity();

                    if(response.getStatusLine().getStatusCode()!=200){
                        Looper.prepare();
                        Toast toast=Toast.makeText(getApplicationContext(),"异常", Toast.LENGTH_SHORT);
                        toast.setGravity(Gravity.TOP| Gravity.CENTER, -50, 100);
                        toast.show();
                        Looper.loop();
                    }

                        String result = EntityUtils.toString(response.getEntity());

                        //检查php端返回的信息
                        if(result.equals("Error")){
                            Looper.prepare();
                            Toast toast=Toast.makeText(getApplicationContext(),result, Toast.LENGTH_SHORT);
                            toast.setGravity(Gravity.TOP| Gravity.CENTER, -50, 100);
                            toast.show();
                            Looper.loop();
                        }

                        else{
                            Looper.prepare();
                            ArrayList Listfirst = new ArrayList();
                            ArrayList Listlast = new ArrayList();
                            ArrayList Listage = new ArrayList();

                           JSONArray mJSONArray=  new JSONArray(result);
                          for(int i =  0 ; i < mJSONArray.length(); i++)
                            {
                                JSONObject jsonItem = mJSONArray.getJSONObject(i);
                                String firstname = jsonItem.getString("menu_name");
                                String lastname = jsonItem.getString("url");
                                String age = jsonItem.getString("remark");
                                Listfirst.add(firstname);
                                Listlast.add(lastname);
                                Listage.add(age);
                            }
                            Message msg = new Message();
                            msg.what = 0x123;
                            msg.obj =Listfirst.toString();
                            myHandler.sendMessage(msg);

                            Toast toast=Toast.makeText(getApplicationContext(), result, Toast.LENGTH_SHORT);
                            toast.setGravity(Gravity.TOP|Gravity.CENTER, -50, 100);
                            toast.show();
                            Looper.loop();

                        }

顺便附上php代码，不管有没有用。。。。。。
<?php

$json = "";
$data = array();

class User{
public $menu_name;
public $url;
public $remark;
}

$user = new User();
$user->menu_name="装配单确认";
$user->url="http://192.168.208.1/app/android/1_zp.php";
$user->remark="";
$data[] = $user;

$user = new User();
$user->menu_name="装配滞留确认";
$user->url="http://192.168.208.1/app/android/1_zl.php";
$user->remark="";
$data[] = $user;
$json = json_encode($data);

if(isset($_POST['id']))$id = $_POST['id'];
else  $id ="";

if($id =="C61D4F4"){echo $json;}
else {echo "Error; }
?>