Android PHP MySQL搜索結果到ListView

Question

作為序言，我想說我對Android應用程序開發領域還比較陌生。

我一直在研究一個涉及登錄/注冊系統的Android應用程序，該系統使用JSON從Android應用程序連接到PHP腳本和MySQL。 登錄/注冊功能正常，但是我試圖進行一項活動，該活動能夠搜索注冊用戶並在相同xml布局的ListView中顯示結果。 我的PHP搜索腳本功能正常。

我在網上幾乎到處都看不到相關結果。 如果有人可以幫助我或指出正確的方向，將不勝感激。

提前致謝。

編輯：這是我正在使用的JSON解析器腳本-

公共類JSONParser {

static InputStream is = null;
static JSONObject jObj = null;
static String json = "";

// constructor
public JSONParser() {

}


public JSONObject getJSONFromUrl(final String url) {

    // Making HTTP request
    try {
        // Construct the client and the HTTP request.
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);

        // Execute the POST request and store the response locally.
        HttpResponse httpResponse = httpClient.execute(httpPost);
        // Extract data from the response.
        HttpEntity httpEntity = httpResponse.getEntity();
        // Open an inputStream with the data content.
        is = httpEntity.getContent();

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        // Create a BufferedReader to parse through the inputStream.
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        // Declare a string builder to help with the parsing.
        StringBuilder sb = new StringBuilder();
        // Declare a string to store the JSON object data in string form.
        String line = null;

        // Build the string until null.
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }

        // Close the input stream.
        is.close();
        // Convert the string builder data to an actual string.
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

    // Try to 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 the JSON Object.
    return jObj;

}


// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
        List<NameValuePair> params) {

    // Making HTTP request
    try {

        // check for request method
        if(method == "POST"){
            // request method is POST
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        }else if(method == "GET"){
            // request method is GET
            DefaultHttpClient httpClient = new DefaultHttpClient();
            String paramString = URLEncodedUtils.format(params, "utf-8");
            url += "?" + paramString;
            HttpGet httpGet = new HttpGet(url);

            HttpResponse httpResponse = httpClient.execute(httpGet);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();
        }           

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.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;

}

}

Answer 1

一種簡單的實現方法是使用AsyncTask，如下所示：

package <your package>;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
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.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URLEncodedUtils;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

public class JSONParser {

    static InputStream is = null;
    static JSONObject jObj = null;
    static String json = "";

    // constructor
    public JSONParser() {

    }

    // function get json from url
    // by making HTTP POST or GET mehtod
    public JSONObject makeHttpRequest(String url, String method,
            List<NameValuePair> params) {

        // Making HTTP request
        try {

            // check for request method
            if (method == "POST") {
                // request method is POST
                // defaultHttpClient
                DefaultHttpClient httpClient = new DefaultHttpClient();
                HttpPost httpPost = new HttpPost(url);
                httpPost.setEntity(new UrlEncodedFormEntity(params));

                HttpResponse httpResponse = httpClient.execute(httpPost);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();

            } else if (method == "GET") {
                // request method is GET
                DefaultHttpClient httpClient = new DefaultHttpClient();
                String paramString = URLEncodedUtils.format(params, "utf-8");
                url += "?" + paramString;
                HttpGet httpGet = new HttpGet(url);

                HttpResponse httpResponse = httpClient.execute(httpGet);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();
            }

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            /*BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "iso-8859-1"), 8);*/
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "utf-8"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
            is.close();
            json = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.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;

    }
}

在您的login.java中，您可以使用Async Task從PHP和MySql獲取用戶數據，以下是我已經實現的

注意：您需要向它學習而不是復制代碼，因為.xml是不同的，我在這里沒有php代碼

    package com.ecnu.vendingmachine.login;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ToggleButton;

import com.ecnu.vendingmachine.MainActivity;
import com.ecnu.vendingmachine.MyApplication;
import com.ecnu.vendingmachine.R;
import com.ecnu.vendingmachine.widgets.JSONParser;

public class LoginActivity extends Activity implements OnClickListener {

    private String Tag = "LoginActivity";

    // Progress Dialog
    private ProgressDialog pDialog;

    JSONParser jsonParser = new JSONParser();

    // JSON Node names
    private static final String TAG_SUCCESS = "success";

    private TextView headTitle;
    private EditText loginAccount;
    private EditText loginPassword;
    private Button autoButton;

    private ToggleButton isShowPassword;

    private boolean isAutoLogin = false;

    private LinearLayout registerButton;
    private LinearLayout enterButton;

    private Intent intent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.system_login);

        findViewById();
        initView();
    }

    protected void findViewById() {

        loginAccount = (EditText) this
                .findViewById(R.id.login_account_EditText);
        loginPassword = (EditText) this
                .findViewById(R.id.login_password_EditText);

        isShowPassword = (ToggleButton) this.findViewById(R.id.isShowPassword);
        headTitle = (TextView) findViewById(R.id.headbar_Center_Title);

        registerButton = (LinearLayout) findViewById(R.id.login_Regist_Button);
        enterButton = (LinearLayout) findViewById(R.id.login_Button);
        autoButton = (Button) findViewById(R.id.login_Auto_Button);
    }

    protected void initView() {

        headTitle.setText(R.string.login);
        registerButton.setOnClickListener(this);
        enterButton.setOnClickListener(this);
        autoButton.setOnClickListener(this);

        isShowPassword
                .setOnCheckedChangeListener(new OnCheckedChangeListener() {
                    @Override
                    public void onCheckedChanged(CompoundButton buttonView,
                            boolean isChecked) {

                        String getPassword = loginPassword.getText().toString();

                        if (getPassword.equals("") || getPassword.length() <= 0) {
                        }

                        if (isChecked) {
                            loginPassword.setInputType(0x81);
                            // loginpassword.setTransformationMethod(PasswordTransformationMethod.getInstance());
                        } else {
                            loginPassword.setInputType(0x90);
                            // loginpassword.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
                        }
                        Log.i("togglebutton", "" + isChecked);
                        // loginpassword.postInvalidate();
                    }
                });
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
        case R.id.login_Regist_Button:
            intent = new Intent();
            intent.setClass(LoginActivity.this, RegisterActivity.class);
            startActivity(intent);
            break;

        case R.id.login_Button:
            if (checkPassword() == true && checkAccount() == true) {
                new login().execute();
                break;
            } else {
                break;
            }

        case R.id.login_Auto_Button:
            if (isAutoLogin == false) {
                autoButton.setBackgroundResource(R.drawable.checkbox_focus);
                isAutoLogin = true;
                break;
            } else {
                autoButton.setBackgroundResource(R.drawable.checkbox);
                isAutoLogin = false;
                break;
            }

        default:
            break;
        }
    }

    class login extends AsyncTask<String, String, String> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(LoginActivity.this);
            pDialog.setMessage("loading..");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
            Log.i(Tag, "pDialog");
        }

        protected String doInBackground(String... args) {
            String loginAccountText = loginAccount.getText().toString();
            String loginPasswordText = loginPassword.getText().toString();

            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();

            params.add(new BasicNameValuePair("cellphone", loginAccountText));
            params.add(new BasicNameValuePair("password", loginPasswordText));

            // url to create new product
            MyApplication myApplication = (MyApplication) getApplication();
            String url_login = myApplication.getIP()
                    + "vendingmachine/system_login.php";

            JSONObject json = jsonParser.makeHttpRequest(url_login, "POST",
                    params);

            // check for success tag
            try {
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    // successfully created product
                    String userID = json.getString("userID");
                    int userIntID = Integer.parseInt(userID);
                    myApplication.setUserID(userIntID);
                    finish();
                } else {
                    // failed to create product
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once done
            pDialog.dismiss();
        }

    }

    private boolean checkPassword() {
        String getPassword = loginPassword.getText().toString();
        Log.i(Tag, String.valueOf(getPassword.length()));
        if (getPassword.length() > 5)
            return true;
        else
            return false;
    }

    private boolean checkAccount() {
        String getAccount = loginAccount.getText().toString();
        Log.i(Tag, String.valueOf(getAccount.length()));
        if (getAccount.length() == 11)
            return true;
        else
            return false;
    }
}