我想使用产品的图像按钮从某人的帐户中扣除信用（即产品的费用），这样当他点击图像时，会从他的帐户中扣除信用。问题是我没有想到如何做到这一点，我已经尝试过使用AsyncTask，事情是，我按下了ImageButton，但没有任何反应，就像它甚至不知道我推了它一样。这是代码：
package com.example.battl.qr2;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.preference.PreferenceManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.vision.barcode.Barcode;
import com.squareup.picasso.Picasso;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Profil extends AppCompatActivity {
boolean cof=false;
TextView textView4;
ImageView imageView;
TextView textViewCredits;
Button btnShop;
ImageButton imageButton,imageButton2,imageButton3,imageButton4,imageButton5,imageButton7;
private String credits = "50";
String url="https://zippy.gfycat.com/LiquidBlindDorking.gif";
//出于安全原因，我用X替换了服务器的实际数据
private static final String DB_URL= "jdbc:mysql://X";
private static final String USER = "X";
private static final String PASS = "X";
public SharedPreferences settings;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
settings= PreferenceManager.getDefaultSharedPreferences(this);
setContentView(R.layout.activity_profil);
imageButton=findViewById(R.id.imageButton);
imageButton2=findViewById(R.id.imageButton2);
imageButton3=findViewById(R.id.imageButton3);
imageButton4=findViewById(R.id.imageButton4);
//imageButton5=findViewById(R.id.imageButton5);
//imageButton7=findViewById(R.id.imageButton7);
textViewCredits= findViewById(R.id.textViewCredits);
imageView= findViewById(R.id.imageView);
textView4= findViewById(R.id.textView4);
btnShop=findViewById(R.id.btnShop);
loadImageFromUrl(url);
Picasso.get().load("http://makegoodcoffee.com/coffee-talk/wp-content/uploads/2009/01/espresso.jpg").into(imageButton);
Picasso.get().load("http://makegoodcoffee.com/coffee-talk/wp-content/uploads/2009/01/espresso.jpg").into(imageButton2);
Picasso.get().load("http://hurt2healingmag.com/wp-content/uploads/2013/08/coffee-2.jpg").into(imageButton3);
Picasso.get().load("https://d3mrtwiv4dr09z.cloudfront.net/media/catalog/product/cache/2/image/600x/9df78eab33525d08d6e5fb8d27136e95/1/7/17BRD_BEV_23_EspressoMacchiato_FA_LARGE.png").into(imageButton4);
//Picasso.get().load("https://www.metro.ro/~/media/RO-Metro/image/service-image/articole-utile/cafea-lapte.jpg?h=379&la=ro-RO&w=460").into(imageButton5);
// Picasso.get().load("https://www.nespresso.com/ncp/res/uploads/recipes/1900px_Global_OL_ALL_Coffee%20Moment_Recipe_Latte%20Macchiato_2017_2019.jpg").into(imageButton7);
//final Barcode barcode = getIntent().getParcelableExtra("barcode");
Intent intent = getIntent();
Bundle extras = intent.getExtras();
String getEmail=settings.getString("EMAIL","");
textView4.setText(getEmail);
String getCredits=settings.getString("CREDITE","");
textViewCredits.setText(getCredits);
int costul=0;
btnShop.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
System.out.println("ASTA MERGE");
Toast.makeText(Profil.this,"Asta e buton", Toast.LENGTH_LONG);
}
});
imageButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
System.out.println("ASTA E IMAGINEA");
cof=true;
}
});
}
public void btnConn(View view)
{
Toast.makeText(Profil.this,"Asta e butonu",Toast.LENGTH_LONG);
}
private void loadImageFromUrl(String url)
{
Picasso.get().load(url).into(imageView);
}
private class Send extends AsyncTask<String,String,String>
{
String Msg="";
@Override
protected void onPreExecute() {}
@Override
protected String doInBackground(String... strings)
{
try
{
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection(DB_URL,USER,PASS);
if(conn==null){
Msg="Connection goes wrong";
}else{
final String email=settings.getString("EMAIL","");
String query2 = "SELECT credite FROM reg WHERE email = '" + email + "'";
Statement stmt2 = conn.createStatement();
final ResultSet r2 = stmt2.executeQuery(query2);
r2.next();
final int nrCred=r2.getInt("credite");
final String query3="UPDATE reg SET credite='" + (nrCred-10) + " WHERE email='" + email+ "'";
Statement stmt3 = conn.createStatement();
if(cof=true)
{
stmt3.executeUpdate(query3);
System.out.println("O mers coaiemio");
}
/* imageButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
String query30 = "UPDATE reg SET credite='" + (nrCred - costul) + " WHERE email='" + email + "'";
stmt3.executeUpdate(query30);
Toast.makeText(Profil.this,"Mere Boby",Toast.LENGTH_LONG).show();
} catch (SQLException e) {
e.printStackTrace();
}
}
});
imageButton2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try { String query32 = "UPDATE reg SET credite='" + (nrCred - costul) + " WHERE email='" + email + "'";
stmt3.executeUpdate(query32);
} catch (SQLException e) {
e.printStackTrace();
}
}
});
imageButton3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
stmt3.executeUpdate(query3);
} catch (SQLException e) {
e.printStackTrace();
}
}
});
imageButton4.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
stmt3.executeUpdate(query3);
} catch (SQLException e) {
e.printStackTrace();
}
}
});
imageButton5.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
stmt3.executeUpdate(query3);
} catch (SQLException e) {
e.printStackTrace();
}
}
});
imageButton7.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
try {
stmt3.executeUpdate(query3);
} catch (SQLException e) {
e.printStackTrace();
}
}
});*/
}
conn.close();
}catch (Exception e)
{
Msg="Connection goes wrong 2";
e.printStackTrace();
}
return Msg;
}
@Override
protected void onPostExecute(String msg) {}
}
}