php - Android Studio Mysql PHP - 无法连接数据库

Question

我在尝试在应用程序中建立与数据库的连接时遇到一些困难。

PHP 代码运行良好。我认为问题是我在 Android Studio 中的代码。没有错误，但是当我使用 Android 模拟器运行该项目时，我无法登录，因为它显示“密码错误”。当我尝试注册时，它显示“帐户已创建”，但数据不在数据库中。所以我认为数据库连接有问题。我的应用程序未连接到数据库。我尝试了很多方法，仔细检查了我的 SQL 查询，但就是不明白为什么它不起作用......

这是我的登录类。

package com.example.user.myapplication;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
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.Toast;

import com.google.gson.Gson;

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

import cz.msebera.android.httpclient.HttpEntity;
import cz.msebera.android.httpclient.HttpResponse;
import cz.msebera.android.httpclient.NameValuePair;
import cz.msebera.android.httpclient.client.entity.UrlEncodedFormEntity;
import cz.msebera.android.httpclient.client.methods.HttpPost;
import cz.msebera.android.httpclient.impl.client.DefaultHttpClient;
import cz.msebera.android.httpclient.message.BasicNameValuePair;
import cz.msebera.android.httpclient.params.BasicHttpParams;

import java.net.HttpURLConnection;
import java.net.URL;

public class LoginActivity extends Activity {

    String responseBody = "yas";

    Button signUpButton;
    Button SigninBtn;

    EditText UserIdEd;
    EditText PasswordEd;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login2);

        UserIdEd = (EditText)findViewById(R.id.IdLoginET);
        PasswordEd = (EditText)findViewById(R.id.PasswordLoginET);

        SigninBtn = (Button) findViewById(R.id.loginBtn);

        SigninBtn.setOnClickListener(new View.OnClickListener() {
                                         @Override
                                         public void onClick(View v) {

                                             SignInStudentToApp Temp = new SignInStudentToApp();
                                             Temp.execute();
                                         }
                                     }
        );

        signUpButton = (Button)findViewById(R.id.signUpBtn);
        signUpButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(LoginActivity.this , SignUp.class));
            }
        });
    }


    public class SignInStudentToApp extends AsyncTask<String , Void , Boolean>{

        private ProgressDialog progress;

        public SignInStudentToApp(){

            progress = new ProgressDialog(LoginActivity.this);
        }


        protected void onPreExecute() {
            this.progress.setMessage("Wait please ...");
            this.progress.show();
        }

        @Override
        protected void onPostExecute(final Boolean success) {
            if (progress.isShowing()) {

                if(StudentInfo.student_info != null) {
                    Toast.makeText(LoginActivity.this, "Sign in Successfully", Toast.LENGTH_LONG).show();
                    startActivity(new Intent(LoginActivity.this, WelcomeScreen.class));

                }
                else
                    Toast.makeText(LoginActivity.this, "Wrong Password or Id", Toast.LENGTH_LONG).show();

            }
            progress.dismiss();
        }

        @Override
        protected Boolean doInBackground(String... params) {

            try {
                return SignInCheck();
            } catch (UnsupportedEncodingException e) {
                Log.d("ERORRR", e.getMessage());
            }
            finally {
                return false;
            }
        }
    }


    boolean SignInCheck() throws UnsupportedEncodingException {

        Log.i("Yasser", "start sssssss");
        SignIn userSign = new SignIn();
        userSign.setId(UserIdEd.getText().toString());
        userSign.setPassword(PasswordEd.getText().toString());

         /* Building Parameters */

        DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
        HttpPost httppost = new HttpPost("http://10.0.2.2/ForSever.php");

        // Depends on your web service
        //httppost.setHeader("Content-type", "application/json");

        InputStream inputStream = null;
        String result = null;
        try {
            List<NameValuePair> parameters = new ArrayList<NameValuePair>();
            parameters.add(new BasicNameValuePair("StudentId",userSign.getId()));
            parameters.add(new BasicNameValuePair("pass", userSign.getPassword()));
            httppost.setEntity(new UrlEncodedFormEntity(parameters));
            Log.i("Tests", "start Task for Request");
            HttpResponse response = httpclient.execute(httppost);
            Log.i("Teste", "End Task for Requsest");
            HttpEntity entity = response.getEntity();

            inputStream = entity.getContent();
            // json is UTF-8 by default
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
            StringBuilder sb = new StringBuilder();

            String line = null;
            while ((line = reader.readLine()) != null)
            {
                sb.append(line + "\n");
            }
            result = sb.toString();
            Log.i("Test", result);
        } catch (Exception e) {
            // Oops
        }
        finally {
            try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
        }

        // responseBody =  result ;

        Gson gson = new Gson();
        // StudentInfo.student_info.Init();
        StudentInfo.student_info = gson.fromJson(result,StudentInfo.class);

        Log.i("Test is vote", StudentInfo.student_info.isVote()+"");

        return true;
    }


    @Override
    protected void onPause() {
        super.onPause();

        UserIdEd.setText("") ;
        PasswordEd.setText("");
    }
}

我认为这部分可能有问题:

boolean SignInCheck() throws UnsupportedEncodingException {

    Log.i("Yasser", "start sssssss");
    SignIn userSign = new SignIn();
    userSign.setId(UserIdEd.getText().toString());
    userSign.setPassword(PasswordEd.getText().toString());

    /* Building Parameters */

    DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
    HttpPost httppost = new HttpPost("http://10.0.2.2/ForSever.php");

    // Depends on your web service
    //httppost.setHeader("Content-type", "application/json");

    InputStream inputStream = null;
    String result = null;
    try {
        List<NameValuePair> parameters = new ArrayList<NameValuePair>();
        parameters.add(new BasicNameValuePair("StudentId",userSign.getId()));
        parameters.add(new BasicNameValuePair("pass", userSign.getPassword()));
        httppost.setEntity(new UrlEncodedFormEntity(parameters));
        Log.i("Tests", "start Task for Request");
        HttpResponse response = httpclient.execute(httppost);
        Log.i("Teste", "End Task for Requsest");
        HttpEntity entity = response.getEntity();

        inputStream = entity.getContent();
        // json is UTF-8 by default
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
        StringBuilder sb = new StringBuilder();

        String line = null;
        while ((line = reader.readLine()) != null)
        {
            sb.append(line + "\n");
        }
        result = sb.toString();
        Log.i("Test", result);
    } catch (Exception e) {
        // Oops
    }
    finally {
        try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
    }

    // responseBody =  result ;

    Gson gson = new Gson();
    // StudentInfo.student_info.Init();
    StudentInfo.student_info = gson.fromJson(result,StudentInfo.class);

    Log.i("Test is vote", StudentInfo.student_info.isVote()+"");

    return true;
}


@Override
protected void onPause() {
    super.onPause();

    UserIdEd.setText("") ;
    PasswordEd.setText("");
}

Answer 1

嗨，这里是一个功能齐全的示例项目，它将使用 php 脚本从 Android 应用程序操作 mysql 数据库。我使用volley来发出http请求。

https://github.com/chandima-b-samarasinghe/android-mysql-php

希望这对你有帮助:)