六、android 網絡編程

時間 2019-11-21

標籤 android 網絡編程欄目 Android 简体版

原文原文鏈接

1、基於socket的用法html

　　服務器端：java

　　先啓動一個服務器端的socket ServerSocket svr = new ServerSocket(8989);android

　　開始偵聽請求　　　　　　　　　Socket s = svr.accept();git

　　取得輸入和輸出　　　　　　　　DataInputStream dis = new DataInputStream(s.getInputStream());web

　　　　　　　　　　　　　　　　　DataOutputStream dos = new DataOutputStream(s.getOutputStream());sql

　　Socket 的交互經過流來完成，便是說傳送的字節流，所以任何文件均可以在上面傳送。誰打開的記得要關上。數據庫

　　用DataInputStream/DataOutputStream來進行包裝是由於咱們想要他們對基本數據類型的讀寫功能readInt(),writeInt(),readUTF(),writeUTF()等等。express

　　客戶端：apache

　　發起一個socket鏈接　　　　　　Socket s = new Socket("192.168.1.200",8989);編程

　　取得輸入和輸出　　　　　　　　DataInputStream dis = new DataInputStream(s.getInputStream());

　　　　　　　　　　　　　　　　　DataOutputStream dos = new DataOutputStream(s.getOutputStream());

　　以後就能夠相互通訊了。誰打開的記得要關上。

2、基於Http協議

　　通常是發送請求到某個應用服務器。此時須要用到HttpURLConnection

　　先取得HttpURLConnection urlConn = new URL("http://www.google.com").openConnection();

　　設置標誌　

　　　　urlConn.setDoOutput(true); urlConn.setDoInput(true);//post的狀況下須要設置DoOutput爲true

　　　　urlConn.setRequestMethod("POST");

　　　　urlConn.setUseCache(false);//設置是否用緩存

　　　　urlConn.setRequestProperty("Content-type","application/x-www-form-urlencoded");//設置content－type

　　得到輸出流，便於想服務器發送信息。

　　　　DataOutputStream dos = new DataOutputStream(urlConn.getOutputStream());

　　望流裏面寫請求參數

　　　　dos.writeBytes("name="+URLEncoder.encode("chenmouren","gb2312");

　　　　dos.flush();dos.close();//發送完後立刻關閉。

　　得到輸入流，取數據

　　　　BufferReader reader = new BufferedReader(new InputStreamReader(urlConn.getInputStream()));

　　　　reader.readLine();//用 !=null來判斷是否結束

　　　　reader.close();

　　讀完了記得關閉connection　　urlConn.disconnect();

流程記錄就到此爲止。

三、HttpURLConnection接口
首先須要明確的是，Http通訊中的POST和GET請求方式的不一樣。GET能夠得到靜態頁面，也能夠把參數放在URL字符串後面，傳遞給服務器。而POST方法的參數是放在Http請求中。所以，在編程以前，應當首先明確使用的請求方法，而後再根據所使用的方式選擇相應的編程方式。
HttpURLConnection是繼承於URLConnection類，兩者都是抽象類。其對象主要經過URL的openConnection方法得到。建立方法以下代碼所示：

URL url = new URL("http://www.51cto.com/index.jsp?par=123456");
HttpURLConnection urlConn=(HttpURLConnection)url.openConnection();

經過如下方法能夠對請求的屬性進行一些設置，以下所示：

//設置輸入和輸出流
urlConn.setDoOutput(true);
urlConn.setDoInput(true);
//設置請求方式爲POST
urlConn.setRequestMethod("POST");
//POST請求不能使用緩存
urlConn.setUseCaches(false);
//關閉鏈接
urlConn.disConnection();

HttpURLConnection默認使用GET方式，例以下面代碼所示：

//使用HttpURLConnection打開鏈接
HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
//獲得讀取的內容(流)
InputStreamReader in = new InputStreamReader(urlConn.getInputStream());
// 爲輸出建立BufferedReader
BufferedReader buffer = new BufferedReader(in);
String inputLine = null;
//使用循環來讀取得到的數據
while (((inputLine = buffer.readLine()) != null))
{
//咱們在每一行後面加上一個"\n"來換行
resultData += inputLine + "\n";
}
//關閉InputStreamReader
in.close();
//關閉http鏈接
urlConn.disconnect();

若是須要使用POST方式，則須要setRequestMethod設置。代碼以下：

String httpUrl = "http://192.168.1.110:8080/httpget.jsp";
//得到的數據
String resultData = "";
URL url = null;
try
{
//構造一個URL對象
url = new URL(httpUrl);
}
catch (MalformedURLException e)
{
Log.e(DEBUG_TAG, "MalformedURLException");
}
if (url != null)
{
try
{
// 使用HttpURLConnection打開鏈接
HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
//由於這個是post請求,設立須要設置爲true
urlConn.setDoOutput(true);
urlConn.setDoInput(true);
// 設置以POST方式
urlConn.setRequestMethod("POST");
// Post 請求不能使用緩存
urlConn.setUseCaches(false);
urlConn.setInstanceFollowRedirects(true);
// 配置本次鏈接的Content-type，配置爲application/x-www-form-urlencoded的
urlConn.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
// 鏈接，從postUrl.openConnection()至此的配置必需要在connect以前完成，
// 要注意的是connection.getOutputStream會隱含的進行connect。
urlConn.connect();
//DataOutputStream流
DataOutputStream out = new DataOutputStream(urlConn.getOutputStream());
//要上傳的參數
String content = "par=" + URLEncoder.encode("ABCDEFG", "gb2312");
//將要上傳的內容寫入流中
out.writeBytes(content);
//刷新、關閉
out.flush();
out.close();

四、使用Apache提供的HttpClient接口一樣能夠進行HTTP操做。

對於GET和POST請求方法的操做有所不一樣。GET方法的操做代碼示例以下：

[java] view plain copy

// http地址
String httpUrl = "http://192.168.1.110:8080/httpget.jsp?par=HttpClient_android_Get";
//HttpGet鏈接對象
HttpGet httpRequest = new HttpGet(httpUrl);
//取得HttpClient對象
HttpClient httpclient = new DefaultHttpClient();
//請求HttpClient，取得HttpResponse
HttpResponse httpResponse = httpclient.execute(httpRequest);
//請求成功
if (httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK)
{
//取得返回的字符串
String strResult = EntityUtils.toString(httpResponse.getEntity());
mTextView.setText(strResult);
}
else
{
mTextView.setText("請求錯誤!");
}
}

使用POST方法進行參數傳遞時，須要使用NameValuePair來保存要傳遞的參數。，另外，還須要設置所使用的字符集。代碼以下所示：

[java] view plain copy

// http地址
String httpUrl = "http://192.168.1.110:8080/httpget.jsp";
//HttpPost鏈接對象
HttpPost httpRequest = new HttpPost(httpUrl);
//使用NameValuePair來保存要傳遞的Post參數
List<NameValuePair> params = new ArrayList<NameValuePair>();
//添加要傳遞的參數
params.add(new BasicNameValuePair("par", "HttpClient_android_Post"));
//設置字符集
HttpEntity httpentity = new UrlEncodedFormEntity(params, "gb2312");
//請求httpRequest
httpRequest.setEntity(httpentity);
//取得默認的HttpClient
HttpClient httpclient = new DefaultHttpClient();
//取得HttpResponse
HttpResponse httpResponse = httpclient.execute(httpRequest);
//HttpStatus.SC_OK表示鏈接成功
if (httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK)
{
//取得返回的字符串
String strResult = EntityUtils.toString(httpResponse.getEntity());
mTextView.setText(strResult);
}
else
{
mTextView.setText("請求錯誤!");
}
}

HttpClient其實是對Java提供方法的一些封裝，在HttpURLConnection中的輸入輸出流操做，在這個接口中被統一封裝成了HttpPost(HttpGet)和HttpResponse，這樣，就減小了操做的繁瑣性。

另外，在使用POST方式進行傳輸時，須要進行字符編碼。

五、

package com.study.ws;
import java.io.IOException;
import org.ksoap2.SoapEnvelope;
import org.ksoap2.SoapFault;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.AndroidHttpTransport;
import org.ksoap2.transport.HttpTransportSE;
import org.xmlpull.v1.XmlPullParserException;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.webkit.WebSettings;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class WSClient extends Activity {
private Button search;
private EditText phone;
private TextView result;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
search=(Button)findViewById(R.id.search);
phone=(EditText)findViewById(R.id.phone);
result=(TextView)findViewById(R.id.result);
search.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
String strPhone=phone.getText().toString().trim();
if(!(strPhone.length()==0||strPhone.equals("")))
{
String str = "";
try {
str = getPhoneInfo(strPhone);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
result.setText(str);
}
}
});
}
public String getPhoneInfo(String phoneName) throws IOException, XmlPullParserException
{
//返回的查詢結果
String result = null;
//調用webservice接口的名稱空間
String nameSpace="http://WebXml.com.cn/";
//調用的方法名
String methodName="getMobileCodeInfo";
//將方法名和名稱空間綁定在一塊兒
String SOAP_ACTION = nameSpace + methodName;
//得到返回請求對象
SoapObject request = new SoapObject(nameSpace, methodName);
//設置須要返回請求對象的參數
request.addProperty("mobileCode", phoneName);
request.addProperty("userId", "");
//設置soap的版本
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
SoapEnvelope.VER11);
//設置是否調用的是dotNet開發的
envelope.dotNet = true;
//
envelope.bodyOut = request;
AndroidHttpTransport hts = new AndroidHttpTransport
("http://webservice.webxml.com.cn/WebServices/MobileCodeWS.asmx");
// web service請求
hts.call(SOAP_ACTION, envelope);
// 獲得返回結果
Object o = envelope.getResponse();
result = o.toString();
return result;
}
}

6、1、獲取並使用KSOAP包

在Android SDK中並無提供調用WebService的庫，所以，須要使用第三方的SDK來調用WebService。PC版本的WebService庫很是豐富，但這些對Android來講過於龐大。適合手機的WebService客戶端的SDK有一些，比較經常使用的是KSOAP2。

KSOAP2 地址：http://code.google.com/p/ksoap2-android/

我下載的最新的是： ksoap2-android-assembly-2.5.4-jar-with-dependencies.jar

注意：

我在使用ksoap2-android時犯了一個低級錯誤：使用時報錯誤：The import org.ksoap2 cannot be resolved。
當時分析這個問題時一直覺得是Eclipse出了問題，找了好多方法都不行，
實際是我下載的ksoap2-android-assembly-2.5.4-jar-with-dependencies.jar文件是錯誤的致使的，走了彎路。

在 http://code.google.com/p/ksoap2-android/wiki/HowToUse?tm=2 頁面經過鼠標右鍵連接另存爲存的是同名的一個純文本的Html文件。而不是咱們想要的。

我是在
http://code.google.com/p/ksoap2-android/source/browse/m2-repo/com/google/code/ksoap2-android/ksoap2-android-assembly/2.5.4/ksoap2-android-assembly-2.5.4-jar-with-dependencies.jar 點 View raw file 才正確下載對應文件的。

選擇咱們的項目，右鍵菜單中 Build Path –> Add External Archives… 增長這個下載的包

增長好後，咱們在選擇咱們的項目，右鍵菜單中 Build Path –> Configure Build Path 的 Libraries 中能夠看到下面圖：

二，分如下幾步來調用 WebService

1、指定 WebService 的命名空間和調用方法

import org.ksoap2.serialization.SoapObject;private static final String NAMESPACE = "http://WebXml.com.cn/";private static final String METHOD_NAME = "getWeatherbyCityName"; SoapObject rpc = new SoapObject(NAMESPACE, METHOD_NAME);

SoapObject類的第一個參數表示WebService的命名空間，能夠從WSDL文檔中找到WebService的命名空間。
第二個參數表示要調用的WebService方法名。

2、設置調用方法的參數值，若是沒有參數，能夠省略，設置方法的參數值的代碼以下：

rpc.addProperty("theCityName", "北京");

要注意的是，addProperty方法的第1個參數雖然表示調用方法的參數名，但該參數值並不必定與服務端的WebService類中的方法參數名一致，只要設置參數的順序一致便可。

3、生成調用Webservice方法的SOAP請求信息。

SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);envelope.bodyOut = rpc;envelope.dotNet = true;envelope.setOutputSoapObject(rpc);

建立SoapSerializationEnvelope對象時須要經過SoapSerializationEnvelope類的構造方法設置SOAP協議的版本號。
該版本號須要根據服務端WebService的版本號設置。
在建立SoapSerializationEnvelope對象後，不要忘了設置SOAPSoapSerializationEnvelope類的bodyOut屬性，
該屬性的值就是在第一步建立的SoapObject對象。

4、建立HttpTransportsSE對象。

這裏不要使用 AndroidHttpTransport ht = new AndroidHttpTransport(URL); 這是一個要過時的類

private static String URL = "http://www.webxml.com.cn/webservices/weatherwebservice.asmx";HttpTransportSE ht = new HttpTransportSE(URL);

ht.debug = true;

5、使用call方法調用WebService方法

private static String SOAP_ACTION = "http://WebXml.com.cn/getWeatherbyCityName";ht.call(SOAP_ACTION, envelope);

網上有人說這裏的call的第一個參數爲null，可是通過個人測試，null是不行的。
第2個參數就是在第3步建立的SoapSerializationEnvelope對象。

6、得到WebService方法的返回結果

有兩種方法：

1、使用getResponse方法得到返回數據。

private SoapObject detail;detail =(SoapObject) envelope.getResponse();

2、使用 bodyIn 及 getProperty。

private SoapObject detail;SoapObject result = (SoapObject)envelope.bodyIn;detail = (SoapObject) result.getProperty("getWeatherbyCityNameResult");

7、這時候執行會出錯，提示沒有權限訪問網絡

須要修改 AndroidManifest.xml 文件，賦予相應權限

簡單來講就是增長下面這行配置：<uses-permission android:name="android.permission.INTERNET"></uses-permission>

完整的 AndroidManifest.xml 文件以下：

注：Android 中在代碼中爲了調試寫了system.out.print()輸出項

在菜單：Window-->show view-->other-->找到Android,選擇Logcat 是能夠看到輸出的,
若是你想在一個單獨的窗口看到system.out.print()的輸出的話，能夠在logcat界面點那個綠色的「+」好，

在Filter name 和 By log tag裏面均填入System.out,這樣的話你就能在單獨的界面查看system.out.print()的輸出了！！

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android" package="ghj1976.MyWeather" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".MyWeatherActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <uses-permission android:name="android.permission.INTERNET"></uses-permission> </manifest>

完整的代碼以下：

package ghj1976.MyWeather;import java.io.UnsupportedEncodingException;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.Toast;import org.ksoap2.SoapEnvelope;import org.ksoap2.serialization.SoapObject;import org.ksoap2.serialization.SoapSerializationEnvelope;//import org.ksoap2.transport.AndroidHttpTransport;import org.ksoap2.transport.HttpTransportSE;public class MyWeatherActivity extends Activity { private Button okButton; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); okButton = (Button) this.findViewById(R.id.btn_Search); okButton.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View v) { String city = "北京"; getWeather(city); } }); } private static final String NAMESPACE = "http://WebXml.com.cn/"; // WebService地址 private static String URL = "http://www.webxml.com.cn/webservices/weatherwebservice.asmx"; private static final String METHOD_NAME = "getWeatherbyCityName"; private static String SOAP_ACTION = "http://WebXml.com.cn/getWeatherbyCityName"; private String weatherToday; private SoapObject detail; public void getWeather(String cityName) { try { System.out.println("rpc------"); SoapObject rpc = new SoapObject(NAMESPACE, METHOD_NAME); System.out.println("rpc" + rpc); System.out.println("cityName is " + cityName); rpc.addProperty("theCityName", cityName); SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11); envelope.bodyOut = rpc; envelope.dotNet = true; envelope.setOutputSoapObject(rpc); HttpTransportSE ht = new HttpTransportSE(URL); //AndroidHttpTransport ht = new AndroidHttpTransport(URL); ht.debug = true; ht.call(SOAP_ACTION, envelope); //ht.call(null, envelope); //SoapObject result = (SoapObject)envelope.bodyIn; //detail = (SoapObject) result.getProperty("getWeatherbyCityNameResult"); detail =(SoapObject) envelope.getResponse(); //System.out.println("result" + result); System.out.println("detail" + detail); Toast.makeText(this, detail.toString(), Toast.LENGTH_LONG).show(); parseWeather(detail); return; } catch (Exception e) { e.printStackTrace(); } } private void parseWeather(SoapObject detail) throws UnsupportedEncodingException { String date = detail.getProperty(6).toString(); weatherToday = "今天：" + date.split(" ")[0]; weatherToday = weatherToday + "\n天氣：" + date.split(" ")[1]; weatherToday = weatherToday + "\n氣溫：" + detail.getProperty(5).toString(); weatherToday = weatherToday + "\n風力：" + detail.getProperty(7).toString() + "\n"; System.out.println("weatherToday is " + weatherToday); Toast.makeText(this, weatherToday, Toast.LENGTH_LONG).show(); }}

參考資料

在Android中訪問WebService接口
http://www.cnblogs.com/yy-7years/archive/2011/01/24/1943286.html

Android調用WebService
http://express.ruanko.com/ruanko-express_34/technologyexchange5.html

中國氣象局的WebService地址
http://www.webxml.com.cn/WebServices/WeatherWebService.asmx

Android與服務器端數據交互（基於SOAP協議整合android+webservice）
http://www.cnblogs.com/zhangdongzi/archive/2011/04/19/2020688.html

7、[java] view plain copy

在android程序中運行第一步就是檢測當前有無可用網絡
若是沒有網絡可用就退出程序
if (isConnect(this)==false)
{
new AlertDialog.Builder(this)
.setTitle("網絡錯誤")
.setMessage("網絡鏈接失敗，請確認網絡鏈接")
.setPositiveButton("肯定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface arg0, int arg1) {
// TODO Auto-generated method stub
android.os.Process.killProcess(android.os.Process.myPid());
System.exit(0);
}
}).show();
}
public static boolean isConnect(Context context) {
// 獲取手機全部鏈接管理對象（包括對wi-fi,net等鏈接的管理）
try {
ConnectivityManager connectivity = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity != null) {
// 獲取網絡鏈接管理的對象
NetworkInfo info = connectivity.getActiveNetworkInfo();
if (info != null&& info.isConnected()) {
// 判斷當前網絡是否已經鏈接
if (info.getState() == NetworkInfo.State.CONNECTED) {
return true;
}
}
}
} catch (Exception e) {
// TODO: handle exception
Log.v("error",e.toString());
}
return false;
}
最後一點還得再manifest中添加權限
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

8、[java] view plain copy

public class MainActivity extends Activity
{
private static final String TAG = "MainActivity";
private EditText timelengthText;
private EditText titleText;
private EditText videoText;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//提交上傳按鈕
Button button = (Button) this.findViewById(R.id.button);
timelengthText = (EditText) this.findViewById(R.id.timelength);
videoText = (EditText) this.findViewById(R.id.video);
titleText = (EditText) this.findViewById(R.id.title);
button.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
String title = titleText.getText().toString();
String timelength = timelengthText.getText().toString();
Map<String, String> params = new HashMap<String, String>();
params.put("method", "save");
params.put("title", title);
params.put("timelength", timelength);
try
{
//獲得SDCard的目錄
File uploadFile = new File(Environment.getExternalStorageDirectory(), videoText.getText().toString());
//上傳音頻文件
FormFile formfile = new FormFile("02.mp3", uploadFile, "video", "audio/mpeg");
SocketHttpRequester.post("http://192.168.1.100:8080/videoweb/video/manage.do", params, formfile);
Toast.makeText(MainActivity.this, R.string.success, 1).show();
}
catch (Exception e)
{
Toast.makeText(MainActivity.this, R.string.error, 1).show();
Log.e(TAG, e.toString());
}
}
});
}
}

[java] view plain copy

.上傳工具類，注意裏面構造協議字符串須要根據不一樣的提交表單來處理
public class SocketHttpRequester
{
/**
* 發送xml數據
* @param path 請求地址
* @param xml xml數據
* @param encoding 編碼
* @return
* @throws Exception
*/
public static byte[] postXml(String path, String xml, String encoding) throws Exception{
byte[] data = xml.getBytes(encoding);
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
conn.setRequestMethod("POST");
conn.setDoOutput(true);
conn.setRequestProperty("Content-Type", "text/xml; charset="+ encoding);
conn.setRequestProperty("Content-Length", String.valueOf(data.length));
conn.setConnectTimeout(5 * 1000);
OutputStream outStream = conn.getOutputStream();
outStream.write(data);
outStream.flush();
outStream.close();
if(conn.getResponseCode()==200){
return readStream(conn.getInputStream());
}
return null;
}
/**
* 直接經過HTTP協議提交數據到服務器,實現以下面表單提交功能:
* <FORM METHOD=POST ACTION="http://192.168.0.200:8080/ssi/fileload/test.do" enctype="multipart/form-data">
<INPUT TYPE="text" NAME="name">
<INPUT TYPE="text" NAME="id">
<input type="file" name="imagefile"/>
<input type="file" name="zip"/>
</FORM>
* @param path 上傳路徑(注：避免使用localhost或127.0.0.1這樣的路徑測試，
* 由於它會指向手機模擬器，你可使用http://www.baidu.com或http://192.168.1.10:8080這樣的路徑測試)
* @param params 請求參數 key爲參數名,value爲參數值
* @param file 上傳文件
*/
public static boolean post(String path, Map<String, String> params, FormFile[] files) throws Exception
{
//數據分隔線
final String BOUNDARY = "---------------------------7da2137580612";
//數據結束標誌"---------------------------7da2137580612--"
final String endline = "--" + BOUNDARY + "--/r/n";
//下面兩個for循環都是爲了獲得數據長度參數，依據表單的類型而定
//首先獲得文件類型數據的總長度(包括文件分割線)
int fileDataLength = 0;
for(FormFile uploadFile : files)
{
StringBuilder fileExplain = new StringBuilder();
fileExplain.append("--");
fileExplain.append(BOUNDARY);
fileExplain.append("/r/n");
fileExplain.append("Content-Disposition: form-data;name=/""+ uploadFile.getParameterName()+"/";filename=/""+ uploadFile.getFilname() + "/"/r/n");
fileExplain.append("Content-Type: "+ uploadFile.getContentType()+"/r/n/r/n");
fileExplain.append("/r/n");
fileDataLength += fileExplain.length();
if(uploadFile.getInStream()!=null){
fileDataLength += uploadFile.getFile().length();
}else{
fileDataLength += uploadFile.getData().length;
}
}
//再構造文本類型參數的實體數據
StringBuilder textEntity = new StringBuilder();
for (Map.Entry<String, String> entry : params.entrySet())
{
textEntity.append("--");
textEntity.append(BOUNDARY);
textEntity.append("/r/n");
textEntity.append("Content-Disposition: form-data; name=/""+ entry.getKey() + "/"/r/n/r/n");
textEntity.append(entry.getValue());
textEntity.append("/r/n");
}
//計算傳輸給服務器的實體數據總長度(文本總長度+數據總長度+分隔符)
int dataLength = textEntity.toString().getBytes().length + fileDataLength + endline.getBytes().length;
URL url = new URL(path);
//默認端口號其實能夠不寫
int port = url.getPort()==-1 ? 80 : url.getPort();
//創建一個Socket連接
Socket socket = new Socket(InetAddress.getByName(url.getHost()), port);
//得到一個輸出流（從Android流到web）
OutputStream outStream = socket.getOutputStream();
//下面完成HTTP請求頭的發送
String requestmethod = "POST "+ url.getPath()+" HTTP/1.1/r/n";
outStream.write(requestmethod.getBytes());
//構建accept
String accept = "Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*/r/n";
outStream.write(accept.getBytes());
//構建language
String language = "Accept-Language: zh-CN/r/n";
outStream.write(language.getBytes());
//構建contenttype
String contenttype = "Content-Type: multipart/form-data; boundary="+ BOUNDARY+ "/r/n";
outStream.write(contenttype.getBytes());
//構建contentlength
String contentlength = "Content-Length: "+ dataLength + "/r/n";
outStream.write(contentlength.getBytes());
//構建alive
String alive = "Connection: Keep-Alive/r/n";
outStream.write(alive.getBytes());
//構建host
String host = "Host: "+ url.getHost() +":"+ port +"/r/n";
outStream.write(host.getBytes());
//寫完HTTP請求頭後根據HTTP協議再寫一個回車換行
outStream.write("/r/n".getBytes());
//把全部文本類型的實體數據發送出來
outStream.write(textEntity.toString().getBytes());
//把全部文件類型的實體數據發送出來
for(FormFile uploadFile : files)
{
StringBuilder fileEntity = new StringBuilder();
fileEntity.append("--");
fileEntity.append(BOUNDARY);
fileEntity.append("/r/n");
fileEntity.append("Content-Disposition: form-data;name=/""+ uploadFile.getParameterName()+"/";filename=/""+ uploadFile.getFilname() + "/"/r/n");
fileEntity.append("Content-Type: "+ uploadFile.getContentType()+"/r/n/r/n");
outStream.write(fileEntity.toString().getBytes());
//邊讀邊寫
if(uploadFile.getInStream()!=null)
{
byte[] buffer = new byte[1024];
int len = 0;
while((len = uploadFile.getInStream().read(buffer, 0, 1024))!=-1)
{
outStream.write(buffer, 0, len);
}
uploadFile.getInStream().close();
}
else
{
outStream.write(uploadFile.getData(), 0, uploadFile.getData().length);
}
outStream.write("/r/n".getBytes());
}
//下面發送數據結束標誌，表示數據已經結束
outStream.write(endline.getBytes());
BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
//讀取web服務器返回的數據，判斷請求碼是否爲200，若是不是200，表明請求失敗
if(reader.readLine().indexOf("200")==-1)
{
return false;
}
outStream.flush();
outStream.close();
reader.close();
socket.close();
return true;
}
/**
* 提交數據到服務器
* @param path 上傳路徑(注：避免使用localhost或127.0.0.1這樣的路徑測試，由於它會指向手機模擬器，你可使用http://www.baidu.com或http://192.168.1.10:8080這樣的路徑測試)
* @param params 請求參數 key爲參數名,value爲參數值
* @param file 上傳文件
*/
public static boolean post(String path, Map<String, String> params, FormFile file) throws Exception
{
return post(path, params, new FormFile[]{file});
}
/**
* 提交數據到服務器
* @param path 上傳路徑(注：避免使用localhost或127.0.0.1這樣的路徑測試，由於它會指向手機模擬器，你可使用http://www.baidu.com或http://192.168.1.10:8080這樣的路徑測試)
* @param params 請求參數 key爲參數名,value爲參數值
* @param encode 編碼
*/
public static byte[] postFromHttpClient(String path, Map<String, String> params, String encode) throws Exception
{
//用於存放請求參數
List<NameValuePair> formparams = new ArrayList<NameValuePair>();
for(Map.Entry<String, String> entry : params.entrySet())
{
formparams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
}
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(formparams, encode);
HttpPost httppost = new HttpPost(path);
httppost.setEntity(entity);
//看做是瀏覽器
HttpClient httpclient = new DefaultHttpClient();
//發送post請求
HttpResponse response = httpclient.execute(httppost);
return readStream(response.getEntity().getContent());
}
/**
* 發送請求
* @param path 請求路徑
* @param params 請求參數 key爲參數名稱 value爲參數值
* @param encode 請求參數的編碼
*/
public static byte[] post(String path, Map<String, String> params, String encode) throws Exception
{
//String params = "method=save&name="+ URLEncoder.encode("老畢", "UTF-8")+ "&age=28&";//須要發送的參數
StringBuilder parambuilder = new StringBuilder("");
if(params!=null && !params.isEmpty())
{
for(Map.Entry<String, String> entry : params.entrySet())
{
parambuilder.append(entry.getKey()).append("=")
.append(URLEncoder.encode(entry.getValue(), encode)).append("&");
}
parambuilder.deleteCharAt(parambuilder.length()-1);
}
byte[] data = parambuilder.toString().getBytes();
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
//設置容許對外發送請求參數
conn.setDoOutput(true);
//設置不進行緩存
conn.setUseCaches(false);
conn.setConnectTimeout(5 * 1000);
conn.setRequestMethod("POST");
//下面設置http請求頭
conn.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*");
conn.setRequestProperty("Accept-Language", "zh-CN");
conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
conn.setRequestProperty("Content-Length", String.valueOf(data.length));
conn.setRequestProperty("Connection", "Keep-Alive");
//發送參數
DataOutputStream outStream = new DataOutputStream(conn.getOutputStream());
outStream.write(data);//把參數發送出去
outStream.flush();
outStream.close();
if(conn.getResponseCode()==200)
{
return readStream(conn.getInputStream());
}
return null;
}
/**
* 讀取流
* @param inStream
* @return 字節數組
* @throws Exception
*/
public static byte[] readStream(InputStream inStream) throws Exception
{
ByteArrayOutputStream outSteam = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = -1;
while( (len=inStream.read(buffer)) != -1)
{
outSteam.write(buffer, 0, len);
}
outSteam.close();
inStream.close();
return outSteam.toByteArray();
}
}

[java] view plain copy

public class StreamTool
{
/**
* 從輸入流讀取數據
* @param inStream
* @return
* @throws Exception
*/
public static byte[] readInputStream(InputStream inStream) throws Exception{
ByteArrayOutputStream outSteam = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while( (len = inStream.read(buffer)) !=-1 ){
outSteam.write(buffer, 0, len);
}
outSteam.close();
inStream.close();
return outSteam.toByteArray();
}
}

[java] view plain copy

/**
* 使用JavaBean封裝上傳文件數據
*
*/
public class FormFile
{
//上傳文件的數據
private byte[] data;
private InputStream inStream;
private File file;
//文件名稱
private String filname;
//請求參數名稱
private String parameterName;
//內容類型
private String contentType = "application/octet-stream";
/**
* 上傳小文件，把文件數據先讀入內存
* @param filname
* @param data
* @param parameterName
* @param contentType
*/
public FormFile(String filname, byte[] data, String parameterName, String contentType)
{
this.data = data;
this.filname = filname;
this.parameterName = parameterName;
if(contentType!=null) this.contentType = contentType;
}
/**
* 上傳大文件，一邊讀文件數據一邊上傳
* @param filname
* @param file
* @param parameterName
* @param contentType
*/
public FormFile(String filname, File file, String parameterName, String contentType)
{
this.filname = filname;
this.parameterName = parameterName;
this.file = file;
try
{
this.inStream = new FileInputStream(file);
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
if(contentType!=null) this.contentType = contentType;
}
public File getFile()
{
return file;
}
public InputStream getInStream()
{
return inStream;
}
public byte[] getData()
{
return data;
}
public String getFilname()
{
return filname;
}
public void setFilname(String filname)
{
this.filname = filname;
}
public String getParameterName()
{
return parameterName;
}
public void setParameterName(String parameterName)
{
this.parameterName = parameterName;
}
public String getContentType()
{
return contentType;
}
public void setContentType(String contentType)
{
this.contentType = contentType;
}
}

9、[java] view plain copy

對於Android流量統計來講在2.2版中新加入了TrafficStats類能夠輕鬆獲取，其實自己TrafficStats類也是讀取Linux提供的文件對象系統類型的文本進行解析。android.net.TrafficStats類中，提供了多種靜態方法，能夠直接調用獲取，返回類型均爲 long型，若是返回等於-1表明 UNSUPPORTED 當前設備不支持統計。
Java代碼
static long getMobileRxBytes() //獲取經過Mobile鏈接收到的字節總數，不包含WiFi
static long getMobileRxPackets() //獲取Mobile鏈接收到的數據包總數
static long getMobileTxBytes() //Mobile發送的總字節數
static long getMobileTxPackets() //Mobile發送的總數據包數
static long getTotalRxBytes() //獲取總的接受字節數，包含Mobile和WiFi等
static long getTotalRxPackets() //總的接受數據包數，包含Mobile和WiFi等
static long getTotalTxBytes() //總的發送字節數，包含Mobile和WiFi等
static long getTotalTxPackets() //發送的總數據包數，包含Mobile和WiFi等
static long getUidRxBytes(int uid) //獲取某個網絡UID的接受字節數
static long getUidTxBytes(int uid) //獲取某個網絡UID的發送字節數
總接受流量TrafficStats.getTotalRxBytes()，
總髮送流量TrafficStats.getTotalTxBytes());
不包含WIFI的手機GPRS接收量TrafficStats.getMobileRxBytes());
不包含Wifi的手機GPRS發送量TrafficStats.getMobileTxBytes());
某一個進程的總接收量TrafficStats.getUidRxBytes(Uid));
某一個進程的總髮送量TrafficStats.getUidTxBytes(Uid));
這些都是從第一次啓動程序到最後一次啓動的統計量。並非這篇文章裏所說的「從本次開機到本次關機的統計量」！
用法舉例，注意這裏獲得的單位都是"KB"
Java代碼
public long getTotalRxBytes(){ //獲取總的接受字節數，包含Mobile和WiFi等
return TrafficStats.getTotalRxBytes()==TrafficStats.UNSUPPORTED?0:(TrafficStats.getTotalRxBytes()/1024);
}
public long getTotalTxBytes(){ //總的發送字節數，包含Mobile和WiFi等
return TrafficStats.getTotalTxBytes()==TrafficStats.UNSUPPORTED?0:(TrafficStats.getTotalTxBytes()/1024);
}
public long getMobileRxBytes(){ //獲取經過Mobile鏈接收到的字節總數，不包含WiFi
return TrafficStats.getMobileRxBytes()==TrafficStats.UNSUPPORTED?0:(TrafficStats.getMobileRxBytes()/1024);
}

10、Android開發應用程序時，若是應用程序須要訪問網絡權限,須要在 AndroidManifest.xml 中加入如下代碼<uses-permission android:name=」android.permission.INTERNET」></uses-permission>

若是不知道放在哪一個位置，那就放在</manifest>前邊好了。

一樣的若是用到其它的權限，也須要做出聲明,部分權限列表以下:

android.permission.ACCESS_CHECKIN_PROPERTIES

容許讀寫訪問」properties」表在 checkin數據庫中，改值能夠修改上傳( Allows read/write access to the 「properties」 table in the checkin database, to change values that get uploaded)

android.permission.ACCESS_COARSE_LOCATION

容許一個程序訪問CellID或WiFi熱點來獲取粗略的位置(Allows an application to access coarse (e.g., Cell-ID, WiFi) location)

android.permission.ACCESS_FINE_LOCATION

容許一個程序訪問精良位置(如GPS) (Allows an application to access fine (e.g., GPS) location)

android.permission.ACCESS_LOCATION_EXTRA_COMMANDS

容許應用程序訪問額外的位置提供命令(Allows an application to access extra location provider commands)

android.permission.ACCESS_MOCK_LOCATION

容許程序建立模擬位置提供用於測試(Allows an application to create mock location providers for testing)

android.permission.ACCESS_NETWORK_STATE

容許程序訪問有關GSM網絡信息(Allows applications to access information about networks)

android.permission.ACCESS_SURFACE_FLINGER

容許程序使用SurfaceFlinger底層特性 (Allows an application to use SurfaceFlinger’s low level features)

android.permission.ACCESS_WIFI_STATE

容許程序訪問Wi-Fi網絡狀態信息(Allows applications to access information about Wi-Fi networks)

android.permission.ADD_SYSTEM_SERVICE

容許程序發佈系統級服務(Allows an application to publish system-level services).

android.permission.BATTERY_STATS

容許程序更新手機電池統計信息(Allows an application to update the collected battery statistics)

android.permission.BLUETOOTH

容許程序鏈接到已配對的藍牙設備(Allows applications to connect to paired bluetooth devices)

11、不說廢話，直接說說實現android定位有關的API吧。

這些API都在android.location包下，一共有三個接口和八個類。它們配合使用便可實現定位功能。

三個接口：

GpsStatus.Listener：這是一個當GPS狀態發生改變時，用來接收通知的接口。

GpsStatus.NmeaListener：這是一個用來從GPS裏接收Nmea-0183（爲海用電子設備制定的標準格式）信息的接口。

LocationListener：位置監聽器，用於接收當位置信息發生改變時從LocationManager接收通知的接口。

八個類：

Address：描述地址的類，好比：北京天安門

Criteria：用於描述Location Provider標準的類，標準包括位置精度水平，電量消耗水平，是否獲取海拔、方位信息，是否容許接收付費服務。

GeoCoder：用於處理地理位置的編碼。

GpsSatellite：和GpsStatus聯合使用，用於描述當前GPS衛星的狀態。

GpsStatus：和GpsStatus.Listener聯合使用，用於描述當前GPS衛星的狀態。

Location：用於描述位置信息。

LocationManager：經過此類獲取和調用系統位置服務

LocationProvider：用於描述Location Provider的抽象超類，一個LocationProvider應該可以週期性的報告當前設備的位置信息。

這裏經過一個示例代碼來演示一下android定位。

首先，在AndroidManifest.xml清單文件裏須要加入ACCESS_FINE_LOCATION權限：

1	<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>

其次，實現代碼以下：

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

package com.test;

import java.io.IOException;

import java.util.List;

import android.app.Activity;

import android.location.Address;

import android.location.Criteria;

import android.location.Geocoder;

import android.location.Location;

import android.location.LocationListener;

import android.location.LocationManager;

import android.os.Bundle;

import android.util.Log;

import android.widget.Toast;

public class PositionActivity extends Activity {

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

// 獲取到LocationManager對象

LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

// 建立一個Criteria對象

Criteria criteria = new Criteria();

// 設置粗略精確度

criteria.setAccuracy(Criteria.ACCURACY_COARSE);

// 設置是否須要返回海拔信息

criteria.setAltitudeRequired(false);

// 設置是否須要返回方位信息

criteria.setBearingRequired(false);

// 設置是否容許付費服務

criteria.setCostAllowed(true);

// 設置電量消耗等級

criteria.setPowerRequirement(Criteria.POWER_HIGH);

// 設置是否須要返回速度信息

criteria.setSpeedRequired(false);

// 根據設置的Criteria對象，獲取最符合此標準的provider對象 41

String currentProvider = locationManager

.getBestProvider(criteria, true);

Log.d("Location", "currentProvider: " + currentProvider);

// 根據當前provider對象獲取最後一次位置信息 44

Location currentLocation = locationManager

.getLastKnownLocation(currentProvider);

// 若是位置信息爲null，則請求更新位置信息 46

if (currentLocation == null) {

locationManager.requestLocationUpdates(currentProvider, 0, 0,

locationListener);

}

// 直到得到最後一次位置信息爲止，若是未得到最後一次位置信息，則顯示默認經緯度 50

// 每隔10秒獲取一次位置信息 51

while (true) {

currentLocation = locationManager

.getLastKnownLocation(currentProvider);

if (currentLocation != null) {

Log.d("Location", "Latitude: " + currentLocation.getLatitude());

Log.d("Location", "location: " + currentLocation.getLongitude());

break;

} else {

Log.d("Location", "Latitude: " + 0);

Log.d("Location", "location: " + 0);

}

try {

Thread.sleep(10000);

} catch (InterruptedException e) {

Log.e("Location", e.getMessage());

}

// 解析地址並顯示 69

Geocoder geoCoder = new Geocoder(this);

try {

int latitude = (int) currentLocation.getLatitude();

int longitude = (int) currentLocation.getLongitude();

List<Address> list = geoCoder.getFromLocation(latitude, longitude,

2);

for (int i = 0; i < list.size(); i++) {

Address address = list.get(i);

Toast.makeText(

PositionActivity.this,

address.getCountryName() + address.getAdminArea()

+ address.getFeatureName(), Toast.LENGTH_LONG)

.show();

}

} catch (IOException e) {

Toast.makeText(PositionActivity.this, e.getMessage(),

Toast.LENGTH_LONG).show();

}

// 建立位置監聽器 85

private LocationListener locationListener = new LocationListener() {

// 位置發生改變時調用 87

@Override

public void onLocationChanged(Location location) {

Log.d("Location", "onLocationChanged");

Log.d("Location",

"onLocationChanged Latitude" + location.getLatitude());

Log.d("Location",

"onLocationChanged location" + location.getLongitude());

}

// provider失效時調用 95

@Override

public void onProviderDisabled(String provider) {

Log.d("Location", "onProviderDisabled");

}

// provider啓用時調用101

@Override

public void onProviderEnabled(String provider) {

Log.d("Location", "onProviderEnabled");

}

// 狀態改變時調用107

@Override

public void onStatusChanged(String provider, int status, Bundle extras) {

Log.d("Location", "onStatusChanged");

}

};

}

因爲代碼裏的Criteria對象對位置精度要求並不高，因此通常會返回「network」做爲provider，而基於network的定位每每會存在必定的位置誤差，這對於須要精肯定位的應用程序來講，顯然不合要求。這時，須要則須要用到基於GPS的定位方法了

12、在前文Android定位功能（一）中，已經大體介紹了一下在Android平臺中，和定位功能相關的類，並舉例獲取了位置信息。可是前文是基於Criteria定製了一個標準，經過getBestProvider()方法由Android系統自動獲取最符合Criteria的LocationProvider，從而實現了定位功能。這樣的作法能最大限度的保證定位功能的可實現性，可是卻沒法保證獲取到的位置信息有最大的準確度。由於除了GPS外，其餘定位方式都或多或少存在着位置偏移。

在實現GPS定位前，先了解一下GPS的部分特性：

1：GPS定位須要依靠3顆或以上的衛星。

2：GPS定位受環境影響較大，在晴朗的空地上，較容易搜索到衛星，而在室內一般是沒法搜索到衛星的。

3：GPS定位須要使用GPS功能模塊，而GPS功能模塊的耗電量是巨大的。

在Android系統中，實現GPS定位的思路大體是：

1、獲取GPS的Location Provider。

2、將此Provider傳入到requestLocationUpdates()方法，讓Android系統獲知搜索位置方式。

3、建立實現了GpsStatus.Listener接口的對象，重寫onGpsStatusChanged()方法，向LocationManager添加次監聽器，檢測衛星狀態。（可選步驟）

根據以上思路，仿照Android定位功能（一）中的例子，能夠很容易的獲得如下實現代碼：（此代碼的實現前提是GPS功能模塊處於打開狀態）

100

101

102

103

104

105

106

107

108

109

110

public class MainActivity extends Activity {

private LocationManager locationManager;

private GpsStatus gpsstatus;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

// 獲取到LocationManager對象

locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

// 根據設置的Criteria對象，獲取最符合此標準的provider對象

String currentProvider = locationManager.getProvider(

LocationManager.GPS_PROVIDER).getName();

// 根據當前provider對象獲取最後一次位置信息

Location currentLocation = locationManager

.getLastKnownLocation(currentProvider);

// 若是位置信息爲null，則請求更新位置信息

if (currentLocation == null) {

locationManager.requestLocationUpdates(currentProvider, 0, 0,

locationListener);

}

// 增長GPS狀態監聽器

locationManager.addGpsStatusListener(gpsListener);

// 直到得到最後一次位置信息爲止，若是未得到最後一次位置信息，則顯示默認經緯度

// 每隔10秒獲取一次位置信息

while (true) {

currentLocation = locationManager

.getLastKnownLocation(currentProvider);

if (currentLocation != null) {

Log.d("Location", "Latitude: " + currentLocation.getLatitude());

Log.d("Location", "location: " + currentLocation.getLongitude());

break;

} else {

Log.d("Location", "Latitude: " + 0);

Log.d("Location", "location: " + 0);

}

try {

Thread.sleep(10000);

} catch (InterruptedException e) {

Log.e("Location", e.getMessage());

}

private GpsStatus.Listener gpsListener = new GpsStatus.Listener() {

// GPS狀態發生變化時觸發

@Override

public void onGpsStatusChanged(int event) {

// 獲取當前狀態

gpsstatus = locationManager.getGpsStatus(null);

switch (event) {

// 第一次定位時的事件

case GpsStatus.GPS_EVENT_FIRST_FIX:

break;

// 開始定位的事件

case GpsStatus.GPS_EVENT_STARTED:

break;

// 發送GPS衛星狀態事件

case GpsStatus.GPS_EVENT_SATELLITE_STATUS:

Toast.makeText(MainActivity.this,"GPS_EVENT_SATELLITE_STATUS",

Toast.LENGTH_SHORT).show();

Iterable<GpsSatellite> allSatellites = gpsstatus

.getSatellites();

Iterator<GpsSatellite> it = allSatellites.iterator();

int count = 0;

while (it.hasNext()) {

count++;

}

Toast.makeText(MainActivity.this, "Satellite Count:" + count,

Toast.LENGTH_SHORT).show();

break;

// 中止定位事件

case GpsStatus.GPS_EVENT_STOPPED:

Log.d("Location", "GPS_EVENT_STOPPED");

break;

}

};

// 建立位置監聽器

private LocationListener locationListener = new LocationListener() {

// 位置發生改變時調用

@Override

public void onLocationChanged(Location location) {

Log.d("Location", "onLocationChanged");

}

// provider失效時調用

@Override

public void onProviderDisabled(String provider) {

Log.d("Location", "onProviderDisabled");

}

// provider啓用時調用

@Override

public void onProviderEnabled(String provider) {

Log.d("Location", "onProviderEnabled");

}

// 狀態改變時調用

@Override

public void onStatusChanged(String provider, int status, Bundle extras) {

Log.d("Location", "onStatusChanged");

}

};

}

13、[java] view plain copy

package wizzer.cn.app;
public class SecBase64 {
private static final byte[] encodingTable = { (byte) 'A', (byte) 'B',
(byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
(byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L',
(byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q',
(byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V',
(byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a',
(byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f',
(byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k',
(byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p',
(byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
(byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z',
(byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4',
(byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9',
(byte) '+', (byte) '/' };
private static final byte[] decodingTable;
static {
decodingTable = new byte[128];
for (int i = 0; i < 128; i++) {
decodingTable[i] = (byte) -1;
}
for (int i = 'A'; i <= 'Z'; i++) {
decodingTable[i] = (byte) (i - 'A');
}
for (int i = 'a'; i <= 'z'; i++) {
decodingTable[i] = (byte) (i - 'a' + 26);
}
for (int i = '0'; i <= '9'; i++) {
decodingTable[i] = (byte) (i - '0' + 52);
}
decodingTable['+'] = 62;
decodingTable['/'] = 63;
}
// 加密
public static byte[] encode(byte[] data) {
byte[] bytes;
int modulus = data.length % 3;
if (modulus == 0) {
bytes = new byte[(4 * data.length) / 3];
} else {
bytes = new byte[4 * ((data.length / 3) + 1)];
}
int dataLength = (data.length - modulus);
int a1;
int a2;
int a3;
for (int i = 0, j = 0; i < dataLength; i += 3, j += 4) {
a1 = data[i] & 0xff;
a2 = data[i + 1] & 0xff;
a3 = data[i + 2] & 0xff;
bytes[j] = encodingTable[(a1 >>> 2) & 0x3f];
bytes[j + 1] = encodingTable[((a1 << 4) | (a2 >>> 4)) & 0x3f];
bytes[j + 2] = encodingTable[((a2 << 2) | (a3 >>> 6)) & 0x3f];
bytes[j + 3] = encodingTable[a3 & 0x3f];
}
int b1;
int b2;
int b3;
int d1;
int d2;
switch (modulus) {
case 0:
break;
case 1:
d1 = data[data.length - 1] & 0xff;
b1 = (d1 >>> 2) & 0x3f;
b2 = (d1 << 4) & 0x3f;
bytes[bytes.length - 4] = encodingTable[b1];
bytes[bytes.length - 3] = encodingTable[b2];
bytes[bytes.length - 2] = (byte) '=';
bytes[bytes.length - 1] = (byte) '=';
break;
case 2:
d1 = data[data.length - 2] & 0xff;
d2 = data[data.length - 1] & 0xff;
b1 = (d1 >>> 2) & 0x3f;
b2 = ((d1 << 4) | (d2 >>> 4)) & 0x3f;
b3 = (d2 << 2) & 0x3f;
bytes[bytes.length - 4] = encodingTable[b1];
bytes[bytes.length - 3] = encodingTable[b2];
bytes[bytes.length - 2] = encodingTable[b3];
bytes[bytes.length - 1] = (byte) '=';
break;
}
return bytes;
}
// 解密
public static byte[] decode(byte[] data) {
byte[] bytes;
byte b1;
byte b2;
byte b3;
byte b4;
data = discardNonBase64Bytes(data);
if (data[data.length - 2] == '=') {
bytes = new byte[(((data.length / 4) - 1) * 3) + 1];
} else if (data[data.length - 1] == '=') {
bytes = new byte[(((data.length / 4) - 1) * 3) + 2];
} else {
bytes = new byte[((data.length / 4) * 3)];
}
for (int i = 0, j = 0; i < (data.length - 4); i += 4, j += 3) {
b1 = decodingTable[data[i]];
b2 = decodingTable[data[i + 1]];
b3 = decodingTable[data[i + 2]];
b4 = decodingTable[data[i + 3]];
bytes[j] = (byte) ((b1 << 2) | (b2 >> 4));
bytes[j + 1] = (byte) ((b2 << 4) | (b3 >> 2));
bytes[j + 2] = (byte) ((b3 << 6) | b4);
}
if (data[data.length - 2] == '=') {
b1 = decodingTable[data[data.length - 4]];
b2 = decodingTable[data[data.length - 3]];
bytes[bytes.length - 1] = (byte) ((b1 << 2) | (b2 >> 4));
} else if (data[data.length - 1] == '=') {
b1 = decodingTable[data[data.length - 4]];
b2 = decodingTable[data[data.length - 3]];
b3 = decodingTable[data[data.length - 2]];
bytes[bytes.length - 2] = (byte) ((b1 << 2) | (b2 >> 4));
bytes[bytes.length - 1] = (byte) ((b2 << 4) | (b3 >> 2));
} else {
b1 = decodingTable[data[data.length - 4]];
b2 = decodingTable[data[data.length - 3]];
b3 = decodingTable[data[data.length - 2]];
b4 = decodingTable[data[data.length - 1]];
bytes[bytes.length - 3] = (byte) ((b1 << 2) | (b2 >> 4));
bytes[bytes.length - 2] = (byte) ((b2 << 4) | (b3 >> 2));
bytes[bytes.length - 1] = (byte) ((b3 << 6) | b4);
}
return bytes;
}
// 解密
public static byte[] decode(String data) {
byte[] bytes;
byte b1;
byte b2;
byte b3;
byte b4;
data = discardNonBase64Chars(data);
if (data.charAt(data.length() - 2) == '=') {
bytes = new byte[(((data.length() / 4) - 1) * 3) + 1];
} else if (data.charAt(data.length() - 1) == '=') {
bytes = new byte[(((data.length() / 4) - 1) * 3) + 2];
} else {
bytes = new byte[((data.length() / 4) * 3)];
}
for (int i = 0, j = 0; i < (data.length() - 4); i += 4, j += 3) {
b1 = decodingTable[data.charAt(i)];
b2 = decodingTable[data.charAt(i + 1)];
b3 = decodingTable[data.charAt(i + 2)];
b4 = decodingTable[data.charAt(i + 3)];
bytes[j] = (byte) ((b1 << 2) | (b2 >> 4));
bytes[j + 1] = (byte) ((b2 << 4) | (b3 >> 2));
bytes[j + 2] = (byte) ((b3 << 6) | b4);
}
if (data.charAt(data.length() - 2) == '=') {
b1 = decodingTable[data.charAt(data.length() - 4)];
b2 = decodingTable[data.charAt(data.length() - 3)];
bytes[bytes.length - 1] = (byte) ((b1 << 2) | (b2 >> 4));
} else if (data.charAt(data.length() - 1) == '=') {
b1 = decodingTable[data.charAt(data.length() - 4)];
b2 = decodingTable[data.charAt(data.length() - 3)];
b3 = decodingTable[data.charAt(data.length() - 2)];
bytes[bytes.length - 2] = (byte) ((b1 << 2) | (b2 >> 4));
bytes[bytes.length - 1] = (byte) ((b2 << 4) | (b3 >> 2));
} else {
b1 = decodingTable[data.charAt(data.length() - 4)];
b2 = decodingTable[data.charAt(data.length() - 3)];
b3 = decodingTable[data.charAt(data.length() - 2)];
b4 = decodingTable[data.charAt(data.length() - 1)];
bytes[bytes.length - 3] = (byte) ((b1 << 2) | (b2 >> 4));
bytes[bytes.length - 2] = (byte) ((b2 << 4) | (b3 >> 2));
bytes[bytes.length - 1] = (byte) ((b3 << 6) | b4);
}
return bytes;
}
private static byte[] discardNonBase64Bytes(byte[] data) {
byte[] temp = new byte[data.length];
int bytesCopied = 0;
for (int i = 0; i < data.length; i++) {
if (isValidBase64Byte(data[i])) {
temp[bytesCopied++] = data[i];
}
}
byte[] newData = new byte[bytesCopied];
System.arraycopy(temp, 0, newData, 0, bytesCopied);
return newData;
}
private static String discardNonBase64Chars(String data) {
StringBuffer sb = new StringBuffer();
int length = data.length();
for (int i = 0; i < length; i++) {
if (isValidBase64Byte((byte) (data.charAt(i)))) {
sb.append(data.charAt(i));
}
}
return sb.toString();
}
private static boolean isValidBase64Byte(byte b) {
if (b == '=') {
return true;
} else if ((b < 0) || (b >= 128)) {
return false;
} else if (decodingTable[b] == -1) {
return false;
}
return true;
}
// 測試類
public static void main(String[] args) {
String data = "wizzer@qq.com:etpass";
byte[] result = SecBase64.encode(data.getBytes());// 加密
System.out.println("Basic " + data);
System.out.println("Basic " + new String(result));
System.out.println(new String(SecBase64.decode(new String(result))));// 解密
}
}

14、登錄頁面輸入用戶名和密碼，登錄成功後跳轉到主頁面，失敗時顯示錯誤信息。

傳遞參數時用BasicNameValuePair的List以httpPost.setEntity的方式來作，不能用HttpParams。

[java] view plain copy

userName = (EditText) this.findViewById(R.id.editTextUserName);
password = (EditText) this.findViewById(R.id.editTextPassword);
errorMsg = (TextView) this.findViewById(R.id.textViewLoginMsg);
Button loginBtn = (Button) this.findViewById(R.id.btnLogin);
loginBtn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String result;
/* 發送部分 */
try {
HttpClient httpClient = new DefaultHttpClient();
String address = strUrl;
HttpPost httpPost = new HttpPost(address);
List<BasicNameValuePair> params = new LinkedList<BasicNameValuePair>();
params.add(new BasicNameValuePair("username", userName.getText().toString()));
params.add(new BasicNameValuePair("password", password.getText().toString()));
httpPost.setEntity(new UrlEncodedFormEntity(params, "utf-8")); //將參數填入POST Entity中
HttpResponse httpResponse = httpClient.execute(httpPost);
/* 接收 */
if (httpResponse.getStatusLine().getStatusCode() == 200) {
result = EntityUtils.toString(httpResponse.getEntity());
/* json文本解析 */
JSONTokener jsonParser = new JSONTokener(result);
JSONObject jsonResult = (JSONObject) jsonParser.nextValue();
String status = jsonResult.getString("loginStatus");
String outMessage = jsonResult.getString("outMessage");
if(status.equals("true")){
Intent i = new Intent(LoginActivity.this, MainActivity.class);
i.putExtra("username", outMessage);
startActivityForResult(i, FIRST_REQUEST_CODE);
} else {
errorMsg.setVisibility(View.VISIBLE);
errorMsg.setText(outMessage);
}
} else {
errorMsg.setVisibility(View.VISIBLE);
errorMsg.setText("網絡鏈接問題。CODE:" + httpResponse.getStatusLine().getStatusCode());
}
} catch (JSONException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
});

15、Android Http JSon服務器端和客戶端通訊
服務器端：

[java] view plain copy

package com.web.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import com.web.model.User;
public class JSONServlet extends HttpServlet {
/**
* Constructor of the object.
*/
public JSONServlet() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
List<User> list = new ArrayList<User>();
User u1 = new User();
u1.setId(111);
u1.setUsername("zhang shan");
u1.setPassword("zs");
User u2 = new User();
u2.setId(222);
u2.setUsername("li si");
u2.setPassword("ls");
User u3 = new User();
u3.setId(333);
u3.setUsername("wang wu");
u3.setPassword("ww");
list.add(u1);
list.add(u2);
list.add(u3);
JSONArray ja = new JSONArray();
for (Iterator iterator = list.iterator(); iterator.hasNext();) {
User user = (User) iterator.next();
JSONObject jobj= new JSONObject();
jobj.put("id", user.getId());
jobj.put("username", user.getUsername());
jobj.put("password", user.getPassword());
ja.add(jobj);
}
out.write(ja.toString());
out.flush();
out.close();
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}

[java] view plain copy

手機端：

[java] view plain copy

package com.web.activity;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.ObjectInputStream;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.commons.httpclient.Cookie;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.apache.http.protocol.HTTP;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.web.model.User;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class WebclientActivity extends Activity {
private TextView hello;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
HttpClient httpclient = new DefaultHttpClient();
String uri="http://10.11.72.108:8086/web/JSONServlet";
HttpPost httpReqest = new HttpPost(uri);
try {
HttpResponse response = httpclient.execute(httpReqest);
HttpEntity entity = response.getEntity();
BufferedReader reader = new BufferedReader(new InputStreamReader(entity.getContent()));
StringBuffer sb = new StringBuffer();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
reader.close();
JSONArray ja = new JSONArray(sb.toString());
StringBuffer sb2 = new StringBuffer();
for (int i = 0; i < ja.length(); i++) {
JSONObject jobj= (JSONObject)ja.get(i);
sb2.append("id:").append(jobj.getInt("id")).append(" ");
sb2.append("用戶:").append(jobj.getString("username")).append(" ");
sb2.append("密碼:").append(jobj.getString("password")).append("\r\n");
}
TextView hello = (TextView) findViewById(R.id.helloid);
hello.setText(sb2.toString());
} catch (Exception e) {
Log.i("uuu", e.toString());
}
}
}

16、咱們編寫的是Andorid的HTTP協議多線程斷點下載應用程序。直接使用單線程下載HTTP文件對咱們來講是一件很是簡單的事。那麼，多線程斷點須要什麼功能？

1.多線程下載，

2.支持斷點。

使用多線程的好處：使用多線程下載會提高文件下載的速度。那麼多線程下載文件的過程是：

(1)首先得到下載文件的長度，而後設置本地文件的長度。

HttpURLConnection.getContentLength();//獲取下載文件的長度

RandomAccessFile file = new RandomAccessFile("QQWubiSetup.exe","rwd");

file.setLength(filesize);//設置本地文件的長度

(2)根據文件長度和線程數計算每條線程下載的數據長度和下載位置。

如：文件的長度爲6M，線程數爲3，那麼，每條線程下載的數據長度爲2M，每條線程開始下載的位置以下圖所示。

例如10M大小，使用3個線程來下載，

線程下載的數據長度 (10%3 == 0 ？ 10/3:10/3+1) ,第1，2個線程下載長度是4M，第三個線程下載長度爲2M

下載開始位置：線程id*每條線程下載的數據長度 = ?

下載結束位置：（線程id+1）*每條線程下載的數據長度-1=?

(3)使用Http的Range頭字段指定每條線程從文件的什麼位置開始下載，下載到什麼位置爲止，

如：指定從文件的2M位置開始下載，下載到位置(4M-1byte)爲止

代碼以下：HttpURLConnection.setRequestProperty("Range", "bytes=2097152-4194303");

(4)保存文件，使用RandomAccessFile類指定每條線程從本地文件的什麼位置開始寫入數據。

RandomAccessFile threadfile = new RandomAccessFile("QQWubiSetup.exe ","rwd");

threadfile.seek(2097152);//從文件的什麼位置開始寫入數據

程序結構以下圖所示：

string.xml文件中代碼：

<?xml version="1.0" encoding="utf-8"?>

<resources>
    <string name="hello">Hello World, MainActivity!</string>
    <string name="app_name">Android網絡多線程斷點下載</string>
    <string name="path">下載路徑</string>
    <string name="downloadbutton">下載</string>
    <string name="sdcarderror">SDCard不存在或者寫保護</string>
    <string name="success">下載完成</string>
    <string name="error">下載失敗</string>
</resources>

main.xml文件中代碼：

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:orientation="vertical"

android:layout_width="fill_parent"

android:layout_height="fill_parent">

<TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/path"/>
    <EditText
        android:id="@+id/path"
        android:text="http://www.winrar.com.cn/download/wrar380sc.exe"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content">
    </EditText>
    
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/downloadbutton"
        android:id="@+id/button"/>
    
    <ProgressBar
        android:layout_width="fill_parent"
        android:layout_height="20dip"
        style="?android:attr/progressBarStyleHorizontal"
        android:id="@+id/downloadbar" />
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:id="@+id/resultView" />
    </LinearLayout>

AndroidManifest.xml文件中代碼：

<?xml version="1.0" encoding="utf-8"?>

</manifest>

MainActivity中代碼：

package com.android.downloader;

import java.io.File;

import com.android.network.DownloadProgressListener;
import com.android.network.FileDownloader;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {
    private EditText downloadpathText;
    private TextView resultView;
    private ProgressBar progressBar;

    /**
     * 當Handler被建立會關聯到建立它的當前線程的消息隊列，該類用於往消息隊列發送消息
     * 消息隊列中的消息由當前線程內部進行處理
     */
    private Handler handler = new Handler(){

        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
            case 1:
                progressBar.setProgress(msg.getData().getInt("size"));
                float num = (float)progressBar.getProgress()/(float)progressBar.getMax();
                int result = (int)(num*100);
                resultView.setText(result+ "%");

                if(progressBar.getProgress()==progressBar.getMax()){
                    Toast.makeText(MainActivity.this, R.string.success, 1).show();
                }
                break;
            case -1:
                Toast.makeText(MainActivity.this, R.string.error, 1).show();
                break;
            }
        }
    };

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        downloadpathText = (EditText) this.findViewById(R.id.path);
        progressBar = (ProgressBar) this.findViewById(R.id.downloadbar);
        resultView = (TextView) this.findViewById(R.id.resultView);
        Button button = (Button) this.findViewById(R.id.button);

        button.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                String path = downloadpathText.getText().toString();
                System.out.println(Environment.getExternalStorageState()+"------"+Environment.MEDIA_MOUNTED);

                if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
                    download(path, Environment.getExternalStorageDirectory());
                }else{
                    Toast.makeText(MainActivity.this, R.string.sdcarderror, 1).show();
                }
            }
        });
    }

      /**
       * 主線程(UI線程)
       * 對於顯示控件的界面更新只是由UI線程負責，若是是在非UI線程更新控件的屬性值，更新後的顯示界面不會反映到屏幕上
       * @param path
       * @param savedir
       */
    private void download(final String path, final File savedir) {
        new Thread(new Runnable() {
            @Override
            public void run() {
                FileDownloader loader = new FileDownloader(MainActivity.this, path, savedir, 3);
                progressBar.setMax(loader.getFileSize());//設置進度條的最大刻度爲文件的長度

                try {
                    loader.download(new DownloadProgressListener() {
                        @Override
                        public void onDownloadSize(int size) {//實時獲知文件已經下載的數據長度
                            Message msg = new Message();
                            msg.what = 1;
                            msg.getData().putInt("size", size);
                            handler.sendMessage(msg);//發送消息
                        }
                    });
                } catch (Exception e) {
                    handler.obtainMessage(-1).sendToTarget();
                }
            }
        }).start();
    }

}

DBOpenHelper中代碼：

package com.android.service;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DBOpenHelper extends SQLiteOpenHelper {
    private static final String DBNAME = "down.db";
    private static final int VERSION = 1;

    public DBOpenHelper(Context context) {
        super(context, DBNAME, null, VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE IF NOT EXISTS filedownlog (id integer primary key autoincrement, downpath varchar(100), threadid INTEGER, downlength INTEGER)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS filedownlog");
        onCreate(db);
    }
}

FileService中代碼：

package com.android.service;

import java.util.HashMap;
import java.util.Map;

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;

public class FileService {
    private DBOpenHelper openHelper;

    public FileService(Context context) {
        openHelper = new DBOpenHelper(context);
    }

    /**
     * 獲取每條線程已經下載的文件長度
     * @param path
     * @return
     */
    public Map<Integer, Integer> getData(String path){
        SQLiteDatabase db = openHelper.getReadableDatabase();
        Cursor cursor = db.rawQuery("select threadid, downlength from filedownlog where downpath=?", new String[]{path});
        Map<Integer, Integer> data = new HashMap<Integer, Integer>();

        while(cursor.moveToNext()){
            data.put(cursor.getInt(0), cursor.getInt(1));
        }

        cursor.close();
        db.close();
        return data;
    }

    /**
     * 保存每條線程已經下載的文件長度
     * @param path
     * @param map
     */
    public void save(String path,  Map<Integer, Integer> map){//int threadid, int position
        SQLiteDatabase db = openHelper.getWritableDatabase();
        db.beginTransaction();

        try{
            for(Map.Entry<Integer, Integer> entry : map.entrySet()){
                db.execSQL("insert into filedownlog(downpath, threadid, downlength) values(?,?,?)",
                        new Object[]{path, entry.getKey(), entry.getValue()});
            }
            db.setTransactionSuccessful();
        }finally{
            db.endTransaction();
        }

        db.close();
    }

    /**
     * 實時更新每條線程已經下載的文件長度
     * @param path
     * @param map
     */
    public void update(String path, Map<Integer, Integer> map){
        SQLiteDatabase db = openHelper.getWritableDatabase();
        db.beginTransaction();

        try{
            for(Map.Entry<Integer, Integer> entry : map.entrySet()){
                db.execSQL("update filedownlog set downlength=? where downpath=? and threadid=?",
                        new Object[]{entry.getValue(), path, entry.getKey()});
            }

            db.setTransactionSuccessful();
        }finally{
            db.endTransaction();
        }

        db.close();
    }

    /**
     * 當文件下載完成後，刪除對應的下載記錄
     * @param path
     */
    public void delete(String path){
        SQLiteDatabase db = openHelper.getWritableDatabase();
        db.execSQL("delete from filedownlog where downpath=?", new Object[]{path});
        db.close();
    }

}

DownloadProgressListener中代碼：

package com.android.network;

public interface DownloadProgressListener {
public void onDownloadSize(int size);

}

FileDownloader中代碼：

package com.android.network;

import java.io.File;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.android.service.FileService;

import android.content.Context;
import android.util.Log;

public class FileDownloader {
    private static final String TAG = "FileDownloader";
    private Context context;
    private FileService fileService;

    /* 已下載文件長度 */
    private int downloadSize = 0;

    /* 原始文件長度 */
    private int fileSize = 0;

    /* 線程數 */
    private DownloadThread[] threads;

    /* 本地保存文件 */
    private File saveFile;

    /* 緩存各線程下載的長度*/
    private Map<Integer, Integer> data = new ConcurrentHashMap<Integer, Integer>();

    /* 每條線程下載的長度 */
    private int block;

    /* 下載路徑  */
    private String downloadUrl;

    /**
     * 獲取線程數
     */
    public int getThreadSize() {
        return threads.length;
    }

    /**
     * 獲取文件大小
     * @return
     */
    public int getFileSize() {
        return fileSize;
    }

    /**
     * 累計已下載大小
     * @param size
     */
    protected synchronized void append(int size) {
        downloadSize += size;
    }

    /**
     * 更新指定線程最後下載的位置
     * @param threadId 線程id
     * @param pos 最後下載的位置
     */
    protected synchronized void update(int threadId, int pos) {
        this.data.put(threadId, pos);
        this.fileService.update(this.downloadUrl, this.data);
    }

    /**
     * 構建文件下載器
     * @param downloadUrl 下載路徑
     * @param fileSaveDir 文件保存目錄
     * @param threadNum 下載線程數
     */
    public FileDownloader(Context context, String downloadUrl, File fileSaveDir, int threadNum) {
        try {
            this.context = context;
            this.downloadUrl = downloadUrl;
            fileService = new FileService(this.context);
            URL url = new URL(this.downloadUrl);
            if(!fileSaveDir.exists()) fileSaveDir.mkdirs();
            this.threads = new DownloadThread[threadNum];

            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setConnectTimeout(5*1000);
            conn.setRequestMethod("GET");
            conn.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*");
            conn.setRequestProperty("Accept-Language", "zh-CN");
            conn.setRequestProperty("Referer", downloadUrl);
            conn.setRequestProperty("Charset", "UTF-8");
            conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
            conn.setRequestProperty("Connection", "Keep-Alive");
            conn.connect();
            printResponseHeader(conn);

            if (conn.getResponseCode()==200) {
                this.fileSize = conn.getContentLength();//根據響應獲取文件大小
                if (this.fileSize <= 0) throw new RuntimeException("Unkown file size ");

                String filename = getFileName(conn);//獲取文件名稱
                this.saveFile = new File(fileSaveDir, filename);//構建保存文件
                Map<Integer, Integer> logdata = fileService.getData(downloadUrl);//獲取下載記錄

                if(logdata.size()>0){//若是存在下載記錄
                    for(Map.Entry<Integer, Integer> entry : logdata.entrySet())
                        data.put(entry.getKey(), entry.getValue());//把各條線程已經下載的數據長度放入data中
                }

                if(this.data.size()==this.threads.length){//下面計算全部線程已經下載的數據長度
                    for (int i = 0; i < this.threads.length; i++) {
                        this.downloadSize += this.data.get(i+1);
                    }

                    print("已經下載的長度"+ this.downloadSize);
                }

                //計算每條線程下載的數據長度
                this.block = (this.fileSize % this.threads.length)==0? this.fileSize / this.threads.length : this.fileSize / this.threads.length + 1;
            }else{
                throw new RuntimeException("server no response ");
            }
        } catch (Exception e) {
            print(e.toString());
            throw new RuntimeException("don't connection this url");
        }
    }

    /**
     * 獲取文件名
     * @param conn
     * @return
     */
    private String getFileName(HttpURLConnection conn) {
        String filename = this.downloadUrl.substring(this.downloadUrl.lastIndexOf('/') + 1);

        if(filename==null || "".equals(filename.trim())){//若是獲取不到文件名稱
            for (int i = 0;; i++) {
                String mine = conn.getHeaderField(i);

                if (mine == null) break;

                if("content-disposition".equals(conn.getHeaderFieldKey(i).toLowerCase())){
                    Matcher m = Pattern.compile(".*filename=(.*)").matcher(mine.toLowerCase());
                    if(m.find()) return m.group(1);
                }
            }

            filename = UUID.randomUUID()+ ".tmp";//默認取一個文件名
        }

        return filename;
    }

    /**
     *  開始下載文件
     * @param listener 監聽下載數量的變化,若是不須要了解實時下載的數量,能夠設置爲null
     * @return 已下載文件大小
     * @throws Exception
     */
    public int download(DownloadProgressListener listener) throws Exception{
        try {
            RandomAccessFile randOut = new RandomAccessFile(this.saveFile, "rw");
            if(this.fileSize>0) randOut.setLength(this.fileSize);
            randOut.close();
            URL url = new URL(this.downloadUrl);

            if(this.data.size() != this.threads.length){
                this.data.clear();

                for (int i = 0; i < this.threads.length; i++) {
                    this.data.put(i+1, 0);//初始化每條線程已經下載的數據長度爲0
                }
            }

            for (int i = 0; i < this.threads.length; i++) {//開啓線程進行下載
                int downLength = this.data.get(i+1);

                if(downLength < this.block && this.downloadSize<this.fileSize){//判斷線程是否已經完成下載,不然繼續下載
                    this.threads[i] = new DownloadThread(this, url, this.saveFile, this.block, this.data.get(i+1), i+1);
                    this.threads[i].setPriority(7);
                    this.threads[i].start();
                }else{
                    this.threads[i] = null;
                }
            }

            this.fileService.save(this.downloadUrl, this.data);
            boolean notFinish = true;//下載未完成

            while (notFinish) {// 循環判斷全部線程是否完成下載
                Thread.sleep(900);
                notFinish = false;//假定所有線程下載完成

                for (int i = 0; i < this.threads.length; i++){
                    if (this.threads[i] != null && !this.threads[i].isFinish()) {//若是發現線程未完成下載
                        notFinish = true;//設置標誌爲下載沒有完成

                        if(this.threads[i].getDownLength() == -1){//若是下載失敗,再從新下載
                            this.threads[i] = new DownloadThread(this, url, this.saveFile, this.block, this.data.get(i+1), i+1);
                            this.threads[i].setPriority(7);
                            this.threads[i].start();
                        }
                    }
                }

                if(listener!=null) listener.onDownloadSize(this.downloadSize);//通知目前已經下載完成的數據長度
            }

            fileService.delete(this.downloadUrl);
        } catch (Exception e) {
            print(e.toString());
            throw new Exception("file download fail");
        }
        return this.downloadSize;
    }

    /**
     * 獲取Http響應頭字段
     * @param http
     * @return
     */
    public static Map<String, String> getHttpResponseHeader(HttpURLConnection http) {
        Map<String, String> header = new LinkedHashMap<String, String>();

        for (int i = 0;; i++) {
            String mine = http.getHeaderField(i);
            if (mine == null) break;
            header.put(http.getHeaderFieldKey(i), mine);
        }

        return header;
    }

    /**
     * 打印Http頭字段
     * @param http
     */
    public static void printResponseHeader(HttpURLConnection http){
        Map<String, String> header = getHttpResponseHeader(http);

        for(Map.Entry<String, String> entry : header.entrySet()){
            String key = entry.getKey()!=null ? entry.getKey()+ ":" : "";
            print(key+ entry.getValue());
        }
    }

    private static void print(String msg){
        Log.i(TAG, msg);
    }
}

DownloadThread 中代碼：

package com.android.network;

import java.io.File;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;

import android.util.Log;

public class DownloadThread extends Thread {
    private static final String TAG = "DownloadThread";
    private File saveFile;
    private URL downUrl;
    private int block;

    /* 下載開始位置  */
    private int threadId = -1;
    private int downLength;
    private boolean finish = false;
    private FileDownloader downloader;

    public DownloadThread(FileDownloader downloader, URL downUrl, File saveFile, int block, int downLength, int threadId) {
        this.downUrl = downUrl;
        this.saveFile = saveFile;
        this.block = block;
        this.downloader = downloader;
        this.threadId = threadId;
        this.downLength = downLength;
    }

    @Override
    public void run() {
        if(downLength < block){//未下載完成
            try {
                HttpURLConnection http = (HttpURLConnection) downUrl.openConnection();
                http.setConnectTimeout(5 * 1000);
                http.setRequestMethod("GET");
                http.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*");
                http.setRequestProperty("Accept-Language", "zh-CN");
                http.setRequestProperty("Referer", downUrl.toString());
                http.setRequestProperty("Charset", "UTF-8");
                int startPos = block * (threadId - 1) + downLength;//開始位置
                int endPos = block * threadId -1;//結束位置
                http.setRequestProperty("Range", "bytes=" + startPos + "-"+ endPos);//設置獲取實體數據的範圍
                http.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
                http.setRequestProperty("Connection", "Keep-Alive");

                InputStream inStream = http.getInputStream();
                byte[] buffer = new byte[1024];
                int offset = 0;
                print("Thread " + this.threadId + " start download from position "+ startPos);
                RandomAccessFile threadfile = new RandomAccessFile(this.saveFile, "rwd");
                threadfile.seek(startPos);

                while ((offset = inStream.read(buffer, 0, 1024)) != -1) {
                    threadfile.write(buffer, 0, offset);
                    downLength += offset;
                    downloader.update(this.threadId, downLength);
                    downloader.append(offset);
                }

                threadfile.close();
                inStream.close();
                print("Thread " + this.threadId + " download finish");
                this.finish = true;
            } catch (Exception e) {
                this.downLength = -1;
                print("Thread "+ this.threadId+ ":"+ e);
            }
        }
    }

    private static void print(String msg){
        Log.i(TAG, msg);
    }

    /**
     * 下載是否完成
     * @return
     */
    public boolean isFinish() {
        return finish;
    }

    /**
     * 已經下載的內容大小
     * @return 若是返回值爲-1,表明下載失敗
     */
    public long getDownLength() {
        return downLength;
    }

}

運行效果以下：

17、Android手機操做系統已經出現就受到了用戶的好評。各大手機廠商也開始利用這一開源的系統抓住商機，發展本身的產業。在這裏先來了解一下這一操做系統的一個小技巧，有關Android顯示網絡圖片的實現。

在Android中顯示一張網絡圖片實際上是超級簡單的，下面就一個很是簡單的例子：

Android顯示網絡圖片Step1：

一、建立你的Activity，本例中以ViewWebImageActivity說明；

二、ViewWebImageActivity中的代碼以下：

[java] view plain copy

String imageUrl = "http://hiphotos.baidu.com/baidu/pic
/item/7d8aebfebf3f9e125c6008d8.jpg";
//這就是你須要顯示的網絡圖片---網上隨便找的
Bitmap bmImg;
ImageView imView;
Button button1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
imView = (ImageView) findViewById(R.id.imview);
imView.setImageBitmap(returnBitMap(imageUrl));
}
public Bitmap returnBitMap(String url) {
URL myFileUrl = null;
Bitmap bitmap = null;
try {
myFileUrl = new URL(url);
} catch (MalformedURLException e) {
e.printStackTrace();
}
try {
HttpURLConnection conn = (HttpURLConnection)
myFileUrl.openConnection();
conn.setDoInput(true);
conn.connect();
InputStream is = conn.getInputStream();
bitmap = BitmapFactory.decodeStream(is);
is.close();
} catch (IOException e) {
e.printStackTrace();
}
return bitmap;
}

三、其中，returnBitMap(String url) 方法就是具體實現網絡圖片轉換成bitmap。

Android顯示網絡圖片Step2：

一、修改你的main.xml文件以下：

[java] view plain copy

< ?xml version="1.0" encoding="utf-8"?>
< LinearLayout xmlns:android=
"http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
< ImageView
android:id="@+id/imview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
/>
< /LinearLayout>

Android顯示網絡圖片Step3：

在你的AndroidManifest.xml文件的< /manifest>節點上面添加< uses-permission android:name="android.permission.INTERNET" />，這是因爲Android有不少的權限限制，不然圖片是不能在你的模擬器上顯示的

18、android

[java] view plain copy

<span style=" font-family: Arial, Tahoma, Verdana, sans-serif; font-size: 14px;">獲取網絡信息須要在AndroidManifest.xml文件中加入相應的權限。 </span>

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

1）判斷是否有網絡鏈接

[java] view plain copy

public boolean isNetworkConnected(Context context) {
if (context != null) {
ConnectivityManager mConnectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
if (mNetworkInfo != null) {
return mNetworkInfo.isAvailable();
}
}
return false;
}

2）判斷WIFI網絡是否可用

[java] view plain copy

public boolean isWifiConnected(Context context) {
if (context != null) {
ConnectivityManager mConnectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mWiFiNetworkInfo = mConnectivityManager
.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (mWiFiNetworkInfo != null) {
return mWiFiNetworkInfo.isAvailable();
}
}
return false;
}

3）判斷MOBILE網絡是否可用

[java] view plain copy

public boolean isMobileConnected(Context context) {
if (context != null) {
ConnectivityManager mConnectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mMobileNetworkInfo = mConnectivityManager
.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (mMobileNetworkInfo != null) {
return mMobileNetworkInfo.isAvailable();
}
}
return false;
}

4）獲取當前網絡鏈接的類型信息

[java] view plain copy

public static int getConnectedType(Context context) {
if (context != null) {
ConnectivityManager mConnectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
if (mNetworkInfo != null && mNetworkInfo.isAvailable()) {
return mNetworkInfo.getType();
}
}
return -1;
}

在開發android應用時，涉及到要進行網絡訪問，時常須要進行網絡狀態的檢查，以提供給用戶必要的提醒。通常能夠經過ConnectivityManager來完成該工做。

ConnectivityManager有四個主要任務：
1、監聽手機網絡狀態（包括GPRS，WIFI， UMTS等)
2、手機狀態發生改變時，發送廣播
3、當一個網絡鏈接失敗時進行故障切換
4、爲應用程序提供能夠獲取可用網絡的高精度和粗糙的狀態
當咱們要在程序中監聽網絡狀態時，只要一下幾個步驟便可：

1、定義一個Receiver重載其中的onReceive函數，在其中完成所須要的功能，如根據WIFI和GPRS是否斷開來改變空間的外觀

[java] view plain copy

connectionReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
ConnectivityManager connectMgr = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
NetworkInfo mobNetInfo = connectMgr.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
NetworkInfo wifiNetInfo = connectMgr.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (!mobNetInfo.isConnected() && !wifiNetInfo.isConnected()) {
Log.i(TAG, "unconnect");
// unconnect network
}else {
// connect network
}
}
};

2、在適當的地方註冊Receiver，能夠在程序中註冊，在onCreate中調用以下函數便可：

[java] view plain copy

IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
registerReceiver(connectionReceiver, intentFilter);

3、在適當時取消註冊Receiver，能夠在程序中取消，在onDestroye中調用以下函數便可：

[java] view plain copy

if (connectionReceiver != null) {
unregisterReceiver(connectionReceiver);
}

Ps：網上還有不少關於使用TelephonyManager 的方法的，方法以下（可是我試了好幾回都有問題，如每次第一次進入一個Activity時會自動收到網絡斷開的信號，每次網絡狀態改變時收到屢次回調且狀態不正確。不知道有什麼要注意的地方，求指點！）

[java] view plain copy

final TelephonyManager mTelephonyMgr = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
mTelephonyMgr.listen(new PhoneStateListener(){
@Override
public void onDataConnectionStateChanged(int state) {
switch(state){
case TelephonyManager.DATA_DISCONNECTED://網絡斷開
break;
case TelephonyManager.DATA_CONNECTING://網絡正在鏈接
break;
case TelephonyManager.DATA_CONNECTED://網絡鏈接上
break;
}
}
}, PhoneStateListener.LISTEN_DATA_CONNECTION_STATE);

至於第二種方法，本人並無去嘗試過。第一種方式仍是比較好用，若是要程序隱藏在後臺的話，建議開個service，將BroadcastReceiver註冊在service，但不要忘了取消註冊。

在測試中遇到過這樣的情況，將一個當前鏈接wifi的路由設備關閉，可是程序並無捕捉到unconnect network，多是由於手機設備馬上鍊接另外一個路由設備了

Android 監控網絡狀態

[java] view plain copy

public static boolean isNetworkAvailable(Context context) {
ConnectivityManager connectivity = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity == null) {
Log.i("NetWorkState", "Unavailabel");
return false;
} else {
NetworkInfo[] info = connectivity.getAllNetworkInfo();
if (info != null) {
for (int i = 0; i < info.length; i++) {
if (info[i].getState() == NetworkInfo.State.CONNECTED) {
Log.i("NetWorkState", "Availabel");
return true;
}
}
}
}
return false;
}

上面這個方法就是判斷網絡是否鏈接的代碼，返回true表示有網絡，返回false表示無網絡。在Android網絡應用程序開發中，常常要判斷網絡鏈接是否可用，所以常常有必要監聽網絡狀態的變化。android的網絡狀態監聽能夠用BroadcastReceiver來接收網絡狀態改變的廣播，具體實現以下

[java] view plain copy

@Override
public void onReceive(Context context, Intent intent) {
Log.e(TAG, "網絡狀態改變");
boolean success = false;
//得到網絡鏈接服務
ConnectivityManager connManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
// State state = connManager.getActiveNetworkInfo().getState();
State state = connManager.getNetworkInfo(
ConnectivityManager.TYPE_WIFI).getState(); // 獲取網絡鏈接狀態
if (State.CONNECTED == state) { // 判斷是否正在使用WIFI網絡
success = true;
}
state = connManager.getNetworkInfo(
ConnectivityManager.TYPE_MOBILE).getState(); // 獲取網絡鏈接狀態
if (State.CONNECTED != state) { // 判斷是否正在使用GPRS網絡
success = true;
}
if (!success) {
Toast.makeText(LocationMapActivity.this, "您的網絡鏈接已中斷", Toast.LENGTH_LONG).show();
}
}

[java] view plain copy

//註冊網絡監聽
IntentFilter filter = new IntentFilter();
filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
registerReceiver(mNetworkStateReceiver, filter);
//在Activity中的onDestroy中:'
unregisterReceiver(mNetworkStateReceiver); //取消監聽

不少朋友在android開發中，都會遇到手機網絡類型判斷，由於就目前的android平臺手機來講：可能會存在4中狀態

1.無網絡（這種狀態多是由於手機停機，網絡沒有開啓，信號很差等緣由）
2.使用WIFI上網
3.CMWAP（中國移動代理）
4.CMNET上網
這四種狀態，若是沒有網絡，確定是沒法請求Internet了，若是是wap就須要爲手機添加中國移動代理，關於爲手機添加中國移動的代理！

下面是網絡判斷的方法：

[java] view plain copy

/**
* @author sky
* Email vipa1888@163.com
* QQ:840950105
* 獲取當前的網絡狀態 -1：沒有網絡 1：WIFI網絡2：wap網絡3：net網絡
* @param context
* @return
*/
public static int getAPNType(Context context){
int netType = -1;
ConnectivityManager connMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
if(networkInfo==null){
return netType;
}
int nType = networkInfo.getType();
if(nType==ConnectivityManager.TYPE_MOBILE){
Log.e("networkInfo.getExtraInfo()", "networkInfo.getExtraInfo() is "+networkInfo.getExtraInfo());
if(networkInfo.getExtraInfo().toLowerCase().equals("cmnet")){
netType = CMNET;
}
else{
netType = CMWAP;
}
}
else if(nType==ConnectivityManager.TYPE_WIFI){
netType = WIFI;
}
return netType;
}