安卓项目4
经历两天的琢磨，终于把android连接服务器端php，读取mysql这一块弄好了。
先说说这几天遇到的问题。
http://wenku.baidu.com/view/87ca3bfa700abb68a982fbca.html
这是我参照的资料，原先我一度认为是不能实例化ServiceLink类，后来在其中弄了好多了Log.i后发现不是这样的。
第一个遇到的问题是
HttpPost httpPost = new HttpPost(url);
其中url一定要写http:// 这点很重要，否则就会报错
03-07 16:16:57.678: E/AndroidRuntime(517): java.lang.IllegalStateException: Target host must not be null, or set in parameters.
其次是要申请权限，在Manifest里申请。
<uses-permission android:name="android.permission.INTERNET">
</uses-permission>
然后就是php端的了。
第一，不能有BOM头，这个可以用notepad++ 来编写无BOM文档。如果没有去掉BOM会弹出以下错误。
JSONException: java.lang.String cannot be converted to JSONObject
第二，一定要是纯JSON输出，中文必须用utf-8，否则也会出现上面的错误。
贴一下我的JAVA代码和PHP代码
//Activity
import org.json.JSONObject;
import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class QRcodeActivity extends Activity {
private ServiceLink servicelink = new ServiceLink();
private Button loginsubmit;
private Button logincancer;
private TextView hostname;
private TextView username;
private TextView password;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_qrcode);
loginsubmit = (Button)findViewById(R.id.loginsubmit);
logincancer = (Button)findViewById(R.id.logincencer);
hostname = (TextView)findViewById(R.id.edithostname);
username = (TextView)findViewById(R.id.editusername);
password = (TextView)findViewById(R.id.editpassword);
Log.i("login","Listener!");
loginsubmit.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// TODO Auto-generated method stub
Log.i("login","reading JSON!");
String hostnamestring = hostname.getText().toString();
Log.i("string",hostnamestring);
String usernamestring = username.getText().toString();
Log.i("string",usernamestring);
String passwordstring = password.getText().toString();
Log.i("string",passwordstring);
Log.i("login","new JSONObject!");
JSONObject jsonobject= new JSONObject();
Log.i("login","setURL");
servicelink.setURL("http://210.38.160.75/QRcode.php");
Log.i("login","serviceLogin");
jsonobject = servicelink.serviceLogin(hostnamestring, usernamestring, passwordstring);
Log.i("login",jsonobject.toString());
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
return true;
}
}
//ServiceLink.class
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.protocol.HTTP;
import org.json.JSONException;
import org.json.JSONObject;
import android.util.Log;
public final class ServiceLink {
/*
功能：连接服务器
API：link(String url);
get(String bundle, String value);
*/
private String url = null;
ServiceLink(){
Log.i("ServiceLink", "ServiceLink");
}
public void setURL(String urll){
this.url = urll;
Log.i("ServiceLink",url);
}
public JSONObject serviceLogin(String hostname,String username, String password){
List<NameValuePair> params = new ArrayList<NameValuePair>();
Log.i("ServiceLink","add params to ArrayList");
params.add(new BasicNameValuePair("operate","login"));
params.add(new BasicNameValuePair("hostname", hostname));
params.add(new BasicNameValuePair("username",username));
params.add(new BasicNameValuePair("password", password));
Log.i("ServiceLink","ready to return value from putParamsToHttp! ");
return putParamsToHttp(params);
}
public JSONObject serviceClean(){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "clean"));
return putParamsToHttp(params);
}
public JSONObject serviceSearch(String form, String field, String value){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "search"));
params.add(new BasicNameValuePair("form", form));
params.add(new BasicNameValuePair("field", field));
params.add(new BasicNameValuePair("value", value));
return putParamsToHttp(params);
}
public JSONObject serviceRead(String form){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "read"));
params.add(new BasicNameValuePair("form", form));
return putParamsToHttp(params);
}
public JSONObject serviceRead(String form, String base, String num){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "read"));
params.add(new BasicNameValuePair("form", form));
params.add(new BasicNameValuePair("base", base));
params.add(new BasicNameValuePair("num", num));
return putParamsToHttp(params);
}
public JSONObject serviceAlter(String form, String field, String id, String value){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "alter"));
params.add(new BasicNameValuePair("form", form));
params.add(new BasicNameValuePair("field", field));
params.add(new BasicNameValuePair("id", id));
params.add(new BasicNameValuePair("value", value));
return putParamsToHttp(params);
}
public JSONObject serviceDelete(String id){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "delete"));
params.add(new BasicNameValuePair("id", id));
return putParamsToHttp(params);
}
public JSONObject serviceInsert(String form,String device,String port,String vlan,String singleMulti, String function, String destDevice){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "Insert"));
params.add(new BasicNameValuePair("form", form));
params.add(new BasicNameValuePair("device", device));
params.add(new BasicNameValuePair("port", port));
params.add(new BasicNameValuePair("vlan", vlan));
params.add(new BasicNameValuePair("singleMulti", singleMulti));
params.add(new BasicNameValuePair("function", function));
params.add(new BasicNameValuePair("destDevice", destDevice));
return putParamsToHttp(params);
}
public JSONObject serviceInsert(String form,String port,String vlan,String singleMulti, String function, String destDevice){
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("operate", "Insert"));
params.add(new BasicNameValuePair("form", form));
params.add(new BasicNameValuePair("port", port));
params.add(new BasicNameValuePair("vlan", vlan));
params.add(new BasicNameValuePair("singleMulti", singleMulti));
params.add(new BasicNameValuePair("function", function));
params.add(new BasicNameValuePair("destDevice", destDevice));
return putParamsToHttp(params);
}
public JSONObject putParamsToHttp(List<NameValuePair> params){
HttpPost httpPost = new HttpPost(url);
InputStream is = null;
JSONObject jObj = null;
String json = null;
Log.i("ServiceLink","ready to put params to http!s");
try {
//设置httpPost请求参数
Log.i("ServiceLink","setEntity");
httpPost.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
//
Log.i("ServiceLink","execute");
HttpResponse httpResponse = new DefaultHttpClient().execute(httpPost);
Log.i("ServiceLink","getStatusCode");
if(httpResponse.getStatusLine().getStatusCode() == 200){
Log.i("ServiceLink","response ok!");
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
Log.i("ServiceLink","getContent");
}
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
Log.i("ServiceLink", "Link failed --ServiceLink");
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
Log.i("ServiceLink", "Link failed --ClientProtocolException");
} catch (IOException e) {
// TODO Auto-generated catch block
Log.i("ServiceLink", "Link failed --IOException");
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
Log.i("ServiceLink","new StringBuilder");
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
Log.i("ServiceLink",line);
}
is.close();
json = sb.toString();
Log.i("ServiceLink",json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
Log.d("json", json.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
//php
<?php
header("Content-Type:text/html; charset=utf-8");
if(!isset($_COOKIE['hostname']))$hostname = "localhost";
else $hostname = $_COOKIE['hostname'];
if(!isset($_COOKIE['username']))$username = "root";
else $username = $_COOKIE['username'];
if(!isset($_COOKIE['password']))$password = "";
else $password = $_COOKIE['password'];
$true = array('success'=>'true');
if(!isset($_POST['operate'])){
print(json_encode("error():请输入操作"));
die(mysql_error());
}
else{
$operate = $_POST['operate'];
switch ($operate){
case "login":
login($_POST['hostname'],$_POST['username'],$_POST['password']);
break;
case "clean":
clean();
break;
case "search":
search($_POST['form'], $_POST['field'], $_POST['value']);
break;
case "read":
if(!isset($_POST['num']))read1($_POST['form']);
else read2($_POST['$form'], $_POST['$base'], $_POST['$num']);
break;
case "alter":
alter($_POST['form'], $_POST['field'], $_POST['id'],$_POST['value']);
break;
case "delete":
delete($_POST['form'],$_POST['id']);
break;
case "insert":
if(isset($_POST['device']))insert1($_POST['form'],$_POST['device'], $_POST['port'], $_POST['vlan'], $_POST['singleMulti'], $_POST['function'], $_POST['destDevice']);
else insert2();
break;
default:
print(json_encode("error():请输入操作"));
die(mysql_error());
}
}
function login($login_hostname,$login_username,$login_password){
//登录
global $true;
$link = @mysql_connect($login_hostname,$login_username,$login_password);
if(!$link){
print(json_encode("error():数据库连接失败"));
die(mysql_error());
}
mysql_query("set names utf8");
$selected_db = mysql_select_db("qrcode");
if(!$selected_db){
die(mysql_error());
}
setcookie("hostname", $login_hostname, time()+ 9999999);
setcookie("username", $login_username, time()+ 9999999);
setcookie("password", $login_password, time()+ 9999999);
print(json_encode($true));return "true";
}
function clean(){
//清楚cookies
mysql_close();
setcookie("hostname", $hostname, time()- 9999999);
setcookie("username", $username, time()- 9999999);
setcookie("password", $password, time()- 9999999);
}
function search($form, $field, $value){
//查询
global $hostname;
global $password;
global $username;
login($hostname,$username,$password);
$sql="select * from $form where $field = $value";
$result = mysql_query($sql);
if(!$result){
print(json_encode("error():数据库查询失败"));
die(mysql_error());
}
while($e=mysql_fetch_assoc($result))
$output[]=$e;
print(json_encode($output));
mysql_close();
print(json_encode($true));return "true";
}
function read1($form){
if(read2($form, 0, 5)){print(json_encode($true));return "true";}
else die(mysql_error());
}
function read2($form, $base, $num){
//读取
global $hostname;
global $password;
global $username;
login($hostname,$username,$password);
$sql = "select * from `$form` LIMIT $base, $num";
$result = mysql_query($sql);
if(!$result){
print(json_encode("error():数据库读取失败"));
die(mysql_error());
}
while($e=mysql_fetch_assoc($result))
$output[]=$e;
print(json_encode($output));
mysql_close();
print(json_encode($true));return "true";
}
function alter($form, $field, $id,$value){
//修改
global $hostname;
global $password;
global $username;
login($hostname,$username,$password);
$sql = "UPDATE `$form` SET `$field`=$value WHERE `id` = $id";
$result = mysql_query($sql);
if(!$result){
print(json_encode("error():数据库更新失败"));
die(mysql_error());
}
print(json_encode("alter success"));
mysql_close();
print(json_encode($true));return "true";
}
function delete($form,$id){
//删除
global $hostname;
global $password;
global $username;
login($hostname,$username,$password);
$sql = "delete from `$form` where `$id` = $id";
$result = mysql_query($sql);
if(!$result ){
print(json_encode("error():数据库删除失败"));
die(mysql_error());
}
print(json_encode("delete success"));
mysql_close();
print(json_encode($true));return "true";
}
function insert1($form,$device, $port, $vlan, $singleMulti, $function, $destDevice){
//插入
global $hostname;
global $password;
global $username;
login($hostname,$username,$password);
$sql="INSERT INTO `form`(`device`, `port`, `VLAN`, `singleMultiMode`, `function`, `destDeviceOrPort`) VALUES ($device,$port,$vlan,$singleMulti,$function,$destDevice)";
$result = mysql_query($sql);
if(!$result ){
print(json_encode("error():数据库插入失败"));
die(mysql_error());
}
print(json_encode("insert success"));
mysql_close();
print(json_encode($true));return "true";
}
function insert2($form, $port, $vlan, $singleMulti, $function, $destDevice){
//插入
global $hostname;
global $password;
global $username;
login($hostname,$username,$password);
$sql="INSERT INTO `form`(`port`, `VLAN`, `singleMultiMode`, `function`, `destDeviceOrPort`) VALUES ($port,$vlan,$singleMulti,$function,$destDevice)";
$result = mysql_query($sql);
if(!$result ){
print(json_encode("error():数据库插入失败"));
die(mysql_error());
}
print(json_encode("insert success"));
mysql_close();
print(json_encode($true));return "true";
}
?>
