使用AsyncTask在Android 4.2中使用JSON填充微调器

我目前正在尝试将我在API10中创建的应用程序的MainActivity的代码转换为API16。根据我所读到的，我必须开始使用ASyncTask来访问URI并在我的应用程序上显示信息。我在2.3中成功地做到了这一点，但在将其转换为JSON之后，我现在面临着一些障碍

本质上，该应用程序所做的是，它接受清单代码，即WAMF33000，点击按钮，微调器将填充该清单中包含的作业。由于我对ASyncTask的概念相当陌生，我想了解我的代码是如何应用于ASyncTask背后的理论的

根据我的代码，我有一些问题：- i） ASyncTask中的哪个代码是正在传递的参数？ ii）我的任务的进度值是多少？ iii）最后，我的返回值是ManifestItems的ArrayList吗

从2.3版本开始，我调用JSON两次——一次加载清单中的委托，第二次加载微调器中选择的委托的详细信息

以下是我的代码：

package com.signonglass;

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


import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import org.json.*;

import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.telephony.TelephonyManager;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity
{
    private final static String POD_URI = "http://192.168.0.105:8092/PodCore.svc";
    private EditText evManifestCode;
    private Spinner list_job;
    private Button btnSubmit;
    private String jobName;
    private Button btnCons;
    ArrayList<ManifestItemObj> jobList = new ArrayList<ManifestItemObj>();
    ArrayList<ConsignmentItems> conItemList = new ArrayList<ConsignmentItems>();
    Consignments retConsignment;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        evManifestCode = (EditText)findViewById(R.id.manifest);
        btnSubmit = (Button)findViewById(R.id.btnSearchManifest);
        list_job = (Spinner)findViewById(R.id.jobSpinner);
        //tvView = (TextView)findViewById(R.id.deviceIdt);



        //TelephonyManager telephonyManager = (TelephonyManager) this.getSystemService(Context.TELEPHONY_SERVICE);
        //String IMEI_Number = telephonyManager.getDeviceId();
        //tvView.setText("IMEI Number: " + IMEI_Number);

    }

    public class MyAsyncTask extends AsyncTask<String, Void, ArrayList<ManifestItemObj>>
    {

        protected void onPreExecute()
        {

        }

        protected void onPostExecute(ArrayList<ManifestItemObj> jobList)
        {

        }

        @Override
        protected ArrayList<ManifestItemObj> doInBackground(String... params)
        {
            //http get request
            HttpGet request = new HttpGet(POD_URI + "/getJobs/" + evManifestCode.getText().toString());
            //set the hedear to get the data in JSON format
            request.setHeader("Accept", "application/json");
            request.setHeader("Content-type", "application/json");

            DefaultHttpClient client = new DefaultHttpClient();
            String theString = new String("");

            try
            {
                //get the response
                HttpResponse response = client.execute(request);
                HttpEntity entity = response.getEntity();
                InputStream is = entity.getContent();
                BufferedReader reader = new BufferedReader(new InputStreamReader(is));

                StringBuilder builder = new StringBuilder();
                String line;
                while ((line = reader.readLine()) != null) {
                                builder.append(line);
                        }
                is.close();
                theString = builder.toString();

                JSONObject jobsJSON = new JSONObject(theString);
                JSONArray jobs = jobsJSON.getJSONArray("getJobsResult");

                for(int i = 1; i < jobs.length(); i++)
                {
                    JSONObject mit = jobs.getJSONObject(i);
                    ManifestItemObj mi = new ManifestItemObj();
                    mi.ManifestItemID = mit.getInt("ManifestItemID");
                    mi.JobType = mit.getString("JobType");
                    mi.FKID = mit.getInt("FKID");
                    jobList.add(mi);
                }      
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }
            return jobList;
        }
    }


    /*private void showToast(String msg)
    {
        // TODO Auto-generated method stub
        Toast.makeText(this, "Toast: " + msg, Toast.LENGTH_LONG).show();
    }*/

    public void onViewConsignment(View view)
    {
        ShowItemsOfManifest(retConsignment);
    }

    public Consignments getConsignmentManifest(String consignment)
    {
        Consignments con = new Consignments();

        try
        {
            DefaultHttpClient client = new DefaultHttpClient();
            String theString = new String("");
            //http get request
            HttpGet request = new HttpGet(POD_URI + "/getJobDetails/" + consignment);
            //set the hedear to get the data in JSON format
            request.setHeader("Accept", "application/json");
            request.setHeader("Content-type", "application/json");

            //get the response
            HttpResponse response = client.execute(request);
            HttpEntity entity = response.getEntity();
            InputStream is = entity.getContent();
            BufferedReader reader = new BufferedReader(new InputStreamReader(is));

            StringBuilder builder = new StringBuilder();
            String line;
            while ((line = reader.readLine()) != null)
            {
                builder.append(line);
            }
            is.close();

            theString = builder.toString();

            JSONObject conJSON = new JSONObject(theString);
            JSONArray cons = conJSON.getJSONArray("getJobDetailsResult");

            for(int i = 0; i < cons.length(); i++)
            {
                JSONObject cObj = cons.getJSONObject(i);
                con.ConsignmentID = cObj.getInt("ConsignmentID");
                con.ConsignmentCreationDate = cObj.getString("ConsignmentCreationDate");
                con.ConsignmentCustRef = cObj.getString("ConsignmentCustRef");
                con.OrderNo = cObj.getString("OrderNo");
                con.ConsignmentActive = cObj.getBoolean("ConsignmentActive");
                con.JobType = cObj.getString("JobType");

                //Client object
                JSONObject clObj = cObj.getJSONObject("Client");
                Clients cl = new Clients();
                cl.ClientId = clObj.getInt("ClientID");
                cl.ClientName = clObj.getString("ClientName");
                con.Clients = cl;

                //ShipTo object
                JSONObject stObj = cObj.getJSONObject("ShipTo");
                ShipTo sto = new ShipTo();
                sto.ShipToId = stObj.getInt("ShipToId");
                sto.ShipToName = stObj.getString("ShipToName");
                sto.ShipToAddress1 = stObj.getString("ShipToAddress1");
                sto.ShipToAddress2 = stObj.getString("ShipToAddress2");
                sto.ShipToCity = stObj.getString("ShipToCity");
                sto.ShipToPostcode = stObj.getString("ShipToPCode");
                sto.ShipToState = stObj.getString("ShipToState");
                con.ShipTo = sto;

                //FreightZone object
                JSONObject fzObj = cObj.getJSONObject("FreightZone");
                FreightZones fz = new FreightZones();
                fz.FreightZoneID = fzObj.getInt("FreightZoneId");
                fz.FreightZone = fzObj.getString("FreightZone");
                con.FreightZone = fz;

                JSONArray conItems = cObj.getJSONArray("ConsignmentItems");

                for(int m = 0; m < conItems.length(); m++)
                {
                    JSONObject cit = conItems.getJSONObject(m);
                    ConsignmentItems ci = new ConsignmentItems();
                    ci.ConsignmentItemID = cit.getInt("ConsignmentItemsID");
                    ci.Quantity = cit.getInt("QTY");

                    //get Product from ConsignmentItems
                    JSONObject pro = cit.getJSONObject("Products");
                    Products prod = new Products();
                    prod.ProductId = pro.getInt("ProductID");
                    prod.ProductModel = pro.getString("ProductModel");
                    prod.ItemsPerCarton = pro.getInt("PerCarton");
                    prod.ProductDescription = pro.getString("Description");
                    prod.Height = (float) pro.getDouble("Height");
                    prod.Length = (float) pro.getDouble("Length");
                    prod.Width = (float) pro.getDouble("Width");
                    prod.Cubic = (float) pro.getDouble("Cubic");
                    ci.Product = prod;
                    conItemList.add(ci);
                    con.ConsignmentItems = conItemList;
                }
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        return con;
    }

    public void ShowItemsOfManifest(Consignments consignments)
    {
        Bundle bundle = new Bundle();
        Intent newIntent = new Intent(this.getApplicationContext(), ConActivity.class);
        newIntent.putExtras(bundle);
        newIntent.putExtra("Consignment", consignments);

        this.startActivity(newIntent);

    }

    public void onSearchClick(View view)
    {
        new MyAsyncTask().execute();
        ManifestItemAdapter mia = new ManifestItemAdapter(MainActivity.this, android.R.layout.simple_spinner_item, jobList);
        list_job.setAdapter(mia); 
    }
}

package com.signonglass；
导入java.io.BufferedReader；
导入java.io.InputStream；
导入java.io.InputStreamReader；
导入java.util.ArrayList；
导入org.apache.http.HttpEntity；
导入org.apache.http.HttpResponse；
导入org.apache.http.NameValuePair；
导入org.apache.http.client.methods.HttpGet；
导入org.apache.http.impl.client.DefaultHttpClient；
导入org.json.*；
导入android.os.AsyncTask；
导入android.os.Build；
导入android.os.Bundle；
导入android.app.Activity；
导入android.app.ProgressDialog；
导入android.content.Context；
导入android.content.Intent；
导入android.telephony.TelephonyManager；
导入android.view.view；
导入android.widget.AdapterView；
导入android.widget.AdapterView.OnItemSelectedListener；
导入android.widget.Button；
导入android.widget.EditText；
导入android.widget.Spinner；
导入android.widget.TextView；
导入android.widget.Toast；
公共类MainActivity扩展了活动
{
私有最终静态字符串POD_URI=”http://192.168.0.105:8092/PodCore.svc";
私有编辑文本代码；
私有微调器列表\u作业；
私人按钮btnSubmit；
私有字符串jobName；
专用按钮；
ArrayList作业列表=新建ArrayList（）；
ArrayList conItemList=新的ArrayList（）；
托运货物；
@凌驾
创建时受保护的void（Bundle savedInstanceState）
{
super.onCreate（savedInstanceState）；
setContentView（R.layout.main）；
evManifestCode=（EditText）findViewById（R.id.manifest）；
btnSubmit=（按钮）findViewById（R.id.btnSearchManifest）；
list_job=（微调器）findViewById（R.id.jobSpinner）；
//tvView=（TextView）findViewById（R.id.deviceIdt）；
//TelephonyManager TelephonyManager=（TelephonyManager）this.getSystemService（Context.TELEPHONY_服务）；
//字符串IMEI_Number=telephonyManager.getDeviceId（）；
//tView.setText（“IMEI编号：+IMEI_编号”）；
}
公共类MyAsyncTask扩展了AsyncTask
{
受保护的void onPreExecute（）
{
}
PostExecute上受保护的void（ArrayList作业列表）
{
}
@凌驾
受保护的ArrayList doInBackground（字符串…参数）
{
//http获取请求
HttpGet请求=新的HttpGet（POD_URI+“/getJobs/”+evManifestCode.getText（）.toString（））；
//设置hedear以获取JSON格式的数据
setHeader（“接受”、“应用程序/json”）；
setHeader（“内容类型”、“应用程序/json”）；
DefaultHttpClient=新的DefaultHttpClient（）；
字符串字符串=新字符串（“”）；
尝试
{
//得到回应
HttpResponse response=client.execute（请求）；
HttpEntity=response.getEntity（）；
InputStream=entity.getContent（）；
BufferedReader reader=新的BufferedReader（新的InputStreamReader（is））；
StringBuilder=新的StringBuilder（）；
弦线；
而（（line=reader.readLine（））！=null）{
builder.append（行）；
}
is.close（）；
theString=builder.toString（）；
JSONObject jobsJSON=新的JSONObject（字符串）；
JSONArray jobs=jobsJSON.getJSONArray（“getJobsResult”）；
对于（int i=1；inew MyAsyncTask().execute(); // you would put params in here if needed such as a URL, String, etc...