在我的应用程序的一个视图中，我有ListView，它使用Listadapter，JSON，PHP等显示来自MySQL数据库的数据。所有这些都有效，但我想弄清楚（没有成功）是如何我可以向PHP发送一个参数，然后我可以检索不是所有的配置文件（在我的应用程序的情况下），而是我想要的取决于用户ID。
这是构成HTTP 的AsynTask代码：
private class GetProfiles extends AsyncTask<String, Void, String>{
private ProgressDialog pDialog;
private String message;
private final GetProfilesListener listener;
/**
* Method to set listener value.
*/
public GetProfiles(GetProfilesListener listener){
this.listener = listener;
}
protected void onPreExecute(){
super.onPreExecute();
pDialog = new ProgressDialog(UserProfiles.this);
pDialog.setTitle("Contacting Server");
pDialog.setMessage("Loading profile(s)...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected String doInBackground(String... params) {
if (params == null )
return null;
String url = params[0];
try {
// create http connection
HttpClient client = new DefaultHttpClient();
HttpGet httpget = new HttpGet(url);
// connect
HttpResponse response = client.execute(httpget);
// get response
HttpEntity entity = response.getEntity();
if(entity == null) {
message = "No response from server";
return null;
}
// get response content and convert it to json string
InputStream is = entity.getContent();
return streamToString(is);
}
catch(IOException e){
message = "No Network Connection";
}
return null;
}
@Override
protected void onPostExecute(String sJson) {
if(sJson == null) {
if(listener != null) listener.onFetchFailure(message);
return;
}
try {
// convert json string to json array
JSONArray aJson = new JSONArray(sJson);
// create profiles list
List<Profiles> profiles = new ArrayList<Profiles>();
for(int i=0; i<aJson.length(); i++) {
JSONObject json = aJson.getJSONObject(i);
Profiles pro = new Profiles();
pro.setProfileName(json.getString("profilename"));
pro.setPetType(json.getString("pettype"));
pro.setUsername(json.getString("username"));
pro.setProfileid(Integer.parseInt(json.getString("profileid")));
pDialog.dismiss();
// add profile to profiles list
profiles.add(pro);
}
//notify the activity that fetch data has been complete
if(listener != null) listener.onFetchComplete(profiles);
} catch (JSONException e) {
message = "Invalid response";
if(listener != null) listener.onFetchFailure(message);
return;
}
}
我知道我的一个参数是url，它显示String url = param[0]我只是不知道如何在代码中添加另一个参数，这些参数将在服务器端使用，以根据id或我尝试建立这样的参数：
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair(TAG_AID, adid));
但它不允许我。
答案 0 :(得分：0)
您可以重载Async任务构造函数并将键值params传递给成员变量，然后在您想要发送http get请求时使用它。请在下面找到代码
private class GetProfiles extends AsyncTask<String, Void, String>{
private ProgressDialog pDialog;
private String message;
private final GetProfilesListener listener;
protected HashMap< String, String > queryStringParams;
/**
* Method to set listener value.
*/
public GetProfiles(GetProfilesListener listener,HashMap< String, String > queryStringParams ){
this.listener = listener;
this.queryStringParams =queryStringParams;
}
protected void onPreExecute(){
super.onPreExecute();
pDialog = new ProgressDialog(UserProfiles.this);
pDialog.setTitle("Contacting Server");
pDialog.setMessage("Loading profile(s)...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected String doInBackground(String... params) {
if (params == null )
return null;
String url = params[0];
//here u can use the queryString hash map parameters that u passed
url+="uid="+queryStringParams.get("UID");//for example
try {
// create http connection
HttpClient client = new DefaultHttpClient();
HttpGet httpget = new HttpGet(url);
// connect
HttpResponse response = client.execute(httpget);
// get response
HttpEntity entity = response.getEntity();
if(entity == null) {
message = "No response from server";
return null;
}
// get response content and convert it to json string
InputStream is = entity.getContent();
return streamToString(is);
}
catch(IOException e){
message = "No Network Connection";
}
return null;
}
所以现在你可以在调用异步任务时发送你的参数，如下面的调用
queryStringParams= new HashMap<String, String>();
queryStringParams.put("UID", "12")
new getListItems(listener, queryStringParams).execute();
答案 1 :(得分：0)
你也可以这样做：
protected String addLocationToUrl(String url){
if(!url.endsWith("?"))
url += "?";
List<NameValuePair> params = new LinkedList<NameValuePair>();
if (lat != 0.0 && lon != 0.0){
params.add(new BasicNameValuePair("lat", String.valueOf(lat)));
params.add(new BasicNameValuePair("lon", String.valueOf(lon)));
}
if (address != null && address.getPostalCode() != null)
params.add(new BasicNameValuePair("postalCode", address.getPostalCode()));
if (address != null && address.getCountryCode() != null)
params.add(new BasicNameValuePair("country",address.getCountryCode()));
params.add(new BasicNameValuePair("user", agent.uniqueId));
String paramString = URLEncodedUtils.format(params, "utf-8");
url += paramString;
return url;
}
答案 2 :(得分：0)
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
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.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity
{
public EditText uname,pwd;
Button btnlog1;
TextView invalid;
public Button btncancel1;
public String db_select;
String mUname;
String mPwd;
String temp;
Intent intObj;
Intent intent = null;
Boolean isInternetPresent = false;
ConnectionDetector cd;
private String SERVICE_URL = "http://10.54.3.208:8080";
private final String TAG = "MainActivity";
public static final String PREFS_NAME = "MyPrefsFile";
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
MainActivity.this.setContentView(R.layout.activity_main);
uname=(EditText)findViewById(R.id.editText1);
pwd=(EditText)findViewById(R.id.editText2);
invalid=(TextView)findViewById(R.id.textView3);
btnlog1=(Button)findViewById(R.id.button1);
//btncancel1=(Button)findViewById(R.id.button2);
//SERVICE_URL=ServerURL.URL+"/msd";
btnlog1.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
mUname=uname.getText().toString();
mPwd=pwd.getText().toString();
SharedPreferences prefs = getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();
editor.putString("EMP_ID",mUname);
editor.putString("EMP_PWD", mPwd);
editor.commit(); //important, otherwise it wouldn't save.
// display("Login clicked");
if(!mUname.equalsIgnoreCase("") && !mPwd.equalsIgnoreCase(""))
{
cd = new ConnectionDetector(getApplicationContext());
isInternetPresent = cd.isConnectingToInternet();
//Toast.makeText(MainActivity.this, isInternetPresent, Toast.LENGTH_LONG).show();
if(isInternetPresent)
{
try
{
validat_user(mUname,mPwd);
}
catch(Exception e)
{
display("Network error.\nPlease check with your network settings.");
uname.setText("");
pwd.setText("");
}
}
else
{
display("No Internet Connection...");
}
}
else
{
invalid.setText("Please enter the data");
}
}
});
}
public void display(String msg)
{
Toast.makeText(MainActivity.this, msg, Toast.LENGTH_LONG).show();
}
private void validat_user(String stg1, String stg2)
{
db_select=stg1;
WebServiceTask wst = new WebServiceTask(WebServiceTask.POST_TASK, this, "Login in progress...");
wst.addNameValuePair("EMP_ID", stg1);
wst.addNameValuePair("EMP_PWD", stg2);
wst.execute(new String[] { SERVICE_URL });
}
@SuppressWarnings("deprecation")
public void no_net()
{
display( "No Network Connection");
final AlertDialog alertDialog = new AlertDialog.Builder(MainActivity.this).create();
alertDialog.setTitle("No Internet Connection");
alertDialog.setMessage("You don't have internet connection.\nElse please check the Internet Connection Settings.");
//alertDialog.setIcon(R.drawable.error_info);
alertDialog.setCancelable(false);
alertDialog.setButton("Close", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int which)
{
alertDialog.cancel();
MainActivity.this.finish();
System.exit(0);
}
});
alertDialog.setButton2("Use Local DataBase", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int which)
{
display( "Accessing local DataBase.....");
alertDialog.cancel();
}
});
alertDialog.show();
}
private class WebServiceTask extends AsyncTask<String, Integer, String> {
public static final int POST_TASK = 1;
private static final String TAG = "WebServiceTask";
// connection timeout, in milliseconds (waiting to connect)
private static final int CONN_TIMEOUT =12000;
// socket timeout, in milliseconds (waiting for data)
private static final int SOCKET_TIMEOUT =12000;
private int taskType = POST_TASK;
private Context mContext = null;
private String processMessage = "Processing...";
private ArrayList<NameValuePair> params = new ArrayList<NameValuePair>();
private ProgressDialog pDlg = null;
public WebServiceTask(int taskType, Context mContext, String processMessage) {
this.taskType = taskType;
this.mContext = mContext;
this.processMessage = processMessage;
}
public void addNameValuePair(String name, String value) {
params.add(new BasicNameValuePair(name, value));
}
@SuppressWarnings("deprecation")
private void showProgressDialog() {
pDlg = new ProgressDialog(mContext);
pDlg.setMessage(processMessage);
pDlg.setProgressDrawable(mContext.getWallpaper());
pDlg.setProgressStyle(ProgressDialog.STYLE_SPINNER);
pDlg.setCancelable(false);
pDlg.show();
}
@Override
protected void onPreExecute() {
showProgressDialog();
}
protected String doInBackground(String... urls) {
String url = urls[0].toString();
String result = "";
HttpResponse response = doResponse(url);
if (response == null) {
return result;
} else {
try {
result = inputStreamToString(response.getEntity().getContent());
} catch (IllegalStateException e) {
Log.e(TAG, e.getLocalizedMessage(), e);
} catch (IOException e) {
Log.e(TAG, e.getLocalizedMessage(), e);
}
catch(Exception e)
{
Log.e(TAG, e.getLocalizedMessage(), e);
}
}
return result;
}
@Override
protected void onPostExecute(String response) {
handleResponse(response);
pDlg.dismiss();
}
// Establish connection and socket (data retrieval) timeouts
private HttpParams getHttpParams() {
HttpParams htpp = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(htpp, CONN_TIMEOUT);
HttpConnectionParams.setSoTimeout(htpp, SOCKET_TIMEOUT);
return htpp;
}
private HttpResponse doResponse(String url) {
// Use our connection and data timeouts as parameters for our
// DefaultHttpClient
HttpClient httpclient = new DefaultHttpClient(getHttpParams());
HttpResponse response = null;
try {
switch (taskType) {
case POST_TASK:
HttpPost httppost= new HttpPost(url);
httppost.setEntity(new UrlEncodedFormEntity(params));
response = httpclient.execute(httppost);
break;
}
}
catch (Exception e) {
// display("Remote DataBase can not be connected.\nPlease check network connection.");
Log.e(TAG, e.getLocalizedMessage(), e);
return null;
}
return response;
}
private String inputStreamToString(InputStream is) {
String line = "";
StringBuilder total = new StringBuilder();
// Wrap a BufferedReader around the InputStream
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
try {
// Read response until the end
while ((line = rd.readLine()) != null) {
total.append(line);
}
} catch (IOException e) {
Log.e(TAG, e.getLocalizedMessage(), e);
}
catch(Exception e)
{
Log.e(TAG, e.getLocalizedMessage(), e);
}
// Return full string
return total.toString();
}
}
public void handleResponse(String response)
{
//display("Response:"+response);
if(!response.equalsIgnoreCase(""))
{
JSONObject jso;
try {
jso = new JSONObject(response);
String status = jso.getString("status");
int valid=jso.getInt("valid");
// display("Welcome : "+UName);
if(valid>0)
{
if( status.equalsIgnoreCase("") || status==null || status.equalsIgnoreCase("Failed"))
{
invalid.setText("Invalid password");
//reset();
pwd.setText("");
}
else
{
//display(status);
intObj=new Intent(MainActivity.this,Design_Activity.class);
startActivity(intObj);
MainActivity.this.finish();
}
}
else
{
invalid.setText("Invalid userid");
uname.setText("");
}
}
catch (JSONException e1) {
Log.e(TAG, e1.getLocalizedMessage(), e1);
}
catch(Exception e)
{
Log.e(TAG, e.getLocalizedMessage(), e);
}
}
else
{
display("Could not able to reach Server!");
}
}
public void reset()
{
pwd.setText("");
uname.setText("");
}
}