将MySQL添加到我的Java程序

我的程序是一个条形码扫描仪，它获取一个值（字符串）并在数据库中搜索项目描述

我无法连接到数据库，我无法在activity_second.xml的文本字段中复制我在activity_main.xml中获得的值（应该在此处进行数据库搜索）

Activity_main.xml

Config.java

---

我的建议是将这个问题分解成可以单独测试的较小部分。连接到数据库并使用使用搜索字符串的WHERE类进行查询不需要UI。让它工作起来，测试它，让其他对象使用它。这真的和？？如果不是那件事的复制品？

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/LinearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:weightSum="1">

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="10dp"
        android:background="#ddd" />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Scan"
        android:onClick="callZXing"
        android:id="@+id/Button" />

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="10dp"
        android:background="#ddd" />

    <TextView
        android:id="@+id/txResult"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Rezultat:"
        android:textSize="20sp" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:text="Is this the correct code?"
        android:id="@+id/textView"
        android:layout_marginTop="70dp"
        android:layout_gravity="center_horizontal" />

    <Button
        style="@style/CaptureTheme"
        android:layout_width="112dp"
        android:layout_height="68dp"
        android:text="Yes"
        android:layout_marginTop="30dp"
        android:id="@+id/button2"
        android:layout_weight="0.10"
        android:layout_gravity="center_horizontal"
        android:onClick="sendSecond" />

    <Button
        style="@style/CaptureTheme"
        android:layout_width="112dp"
        android:layout_height="68dp"
        android:text="No"
        android:layout_marginTop="10dp"
        android:id="@+id/button1"
        android:layout_weight="0.10"
        android:layout_gravity="center_horizontal"
        android:onClick="callZXing" />

</LinearLayout>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <EditText
            android:id="@+id/editTextId"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"/>
        <Button
            android:id="@+id/buttonGet"
            android:text="Get"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

    </LinearLayout>
    <TextView
        android:id="@+id/textViewResult"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />

</LinearLayout>

package br.exemplozxingintegration;

import android.app.ProgressDialog;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.app.Activity;

import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

    public class SecondActivity extends AppCompatActivity implements View.OnClickListener {

        private EditText editTextId;
        private Button buttonGet;
        private TextView textViewResult;

        private ProgressDialog loading;

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

            editTextId = (EditText) findViewById(R.id.editTextId);
            buttonGet = (Button) findViewById(R.id.buttonGet);
            textViewResult = (TextView) findViewById(R.id.textViewResult);

            buttonGet.setOnClickListener(this);
        }

        private void getData() {
            String id = editTextId.getText().toString().trim();
            if (id.equals("")) {
                Toast.makeText(this, "Please enter an id", Toast.LENGTH_LONG).show();
                return;
            }
            loading = ProgressDialog.show(this,"Please wait...","Fetching...",false,false);

            String url = Config.DATA_URL+editTextId.getText().toString().trim();

            StringRequest stringRequest = new StringRequest(url, new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    loading.dismiss();
                    showJSON(response);
                }
            },
                    new Response.ErrorListener() {
                        @Override
                        public void onErrorResponse(VolleyError error) {
                            Toast.makeText(SecondActivity.this,error.getMessage().toString(),Toast.LENGTH_LONG).show();
                        }
                    });

            RequestQueue requestQueue = Volley.newRequestQueue(this);
            requestQueue.add(stringRequest);
        }

        private void showJSON(String response){
            String name="";
            String address="";
            String vc = "";
            try {
                JSONObject jsonObject = new JSONObject(response);
                JSONArray result = jsonObject.getJSONArray(Config.JSON_ARRAY);
                JSONObject collegeData = result.getJSONObject(0);
                name = collegeData.getString(Config.KEY_NAME);
                address = collegeData.getString(Config.KEY_ADDRESS);
                vc = collegeData.getString(Config.KEY_VC);
            } catch (JSONException e) {
                e.printStackTrace();
            }
            textViewResult.setText("Name:\t"+name+"\nDescriere:\t" +address+ "\nImagine:\t"+ vc);
        }

        @Override
        public void onClick(View v) {
            getData();
        }
    }



  //  @Override

    //protected void onCreate(Bundle savedInstanceState) {
       // super.onCreate(savedInstanceState);
      //  setContentView(R.layout.activity_second);
  //  }

//}

package br.exemplozxingintegration;


import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

public class MainActivity extends Activity {
  public static final int REQUEST_CODE = 0;
  private TextView txResult;



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

      txResult = (TextView) findViewById(R.id.txResult);
  }

  public void sendSecond(View view) {
      Intent StartNewActivity  =  new Intent(this,SecondActivity.class);
      startActivity(StartNewActivity);
  }


  public void callZXing(View view){
      Intent it = new Intent(MainActivity.this, com.google.zxing.client.android.CaptureActivity.class);
      startActivityForResult(it, REQUEST_CODE);
  }


  @Override
  public void onActivityResult(int requestCode, int resultCode, Intent data){
      if(REQUEST_CODE == requestCode && RESULT_OK == resultCode){
          txResult.setText("REZULTAT: "+data.getStringExtra("SCAN_RESULT")+" ");
      }
  }
  public class FirstActivity extends Activity {

      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);

          findViewById(R.id.button2).setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
                  TextView textView = (TextView) findViewById(R.id.txResult);
                  Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
                  intent.putExtra("textViewText", textView.getText().toString());
                  startActivity(intent);
              }
          });
      }}
}

package br.exemplozxingintegration;

/**
 * Created by Boghy on 10.02.2016.
 */
public class Config {
    public static final String DATA_URL = "http://192.168.94.1/Android/College/getData.php?id=";
    public static final String KEY_NAME = "title";
    public static final String KEY_ADDRESS = "desc";
    public static final String KEY_VC = "image";
    public static final String JSON_ARRAY = "result";
}