我是新手，Android Studio我想将数据库(我使用MySQL)中的数据显示到中TextView。我也使用Button和RadioButton。单击按钮后，数据将显示在中TextView。这是我的PHP代码：

$host = 'localhost';

$user = 'root';

$pass = 'bismillah';

$database = 'rizka';

$conn = mysqli_connect($host, $user, $pass, $database);

if(!$conn) {

die('Koneksi database gagal: ');

}else{

echo 'berhasil
';

}

$dtkategori = $_GET["kategori"];

$sql = "SELECT * FROM manarul WHERE kategori = '$dtkategori'";

$hasil = mysqli_query($conn, $sql);

while($row = mysqli_fetch_row($hasil)) {

echo "Jumlah Slot = " .$row[1];

echo "\n";

echo "adalah " .$row[2];

echo "\n";

}

?>

这是我的Java代码：

package com.example.googlemaps;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;

import android.os.Bundle;

import java.io.IOException;

import java.io.InputStream;

import java.net.HttpURLConnection;

import java.net.URL;

import java.net.URLConnection;

import android.view.View;

import android.widget.AdapterView;

import android.widget.ArrayAdapter;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ImageView;

import android.widget.RadioButton;

import android.widget.RadioGroup;

import android.widget.Spinner;

import android.widget.TextView;

import android.util.Log;

public class CobaActivity extends AppCompatActivity {

public static final String LOG_TAG ="dataBaru";

String memilih[]={"Silakan Pilih Tempat Parkir", "Masjid Manarul", "Gedung FTSP", "Gedung Rektorat"};

private RadioGroup radioGroupNb;

private RadioButton radioButtonKosong, radioButtonTerisi;

private TextView txt;

private Button pilih, proses;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_coba);

txt = (TextView) findViewById(R.id.TextView03);

pilih = (Button) findViewById(R.id.pilih_parkir1);

proses = (Button) findViewById(R.id.tampil_slot);

radioGroupNb = (RadioGroup) findViewById(R.id.radioGroupNb);

radioButtonKosong = (RadioButton) findViewById(R.id.radioButtonKosong);

radioButtonTerisi = (RadioButton) findViewById(R.id.radioButtonTerisi);

proses.setOnClickListener(new clickproses());

getSupportActionBar().setTitle("Pilih Gedung Parkir");

getSupportActionBar().setDisplayHomeAsUpEnabled(true);

Spinner spinner = (Spinner) findViewById(R.id.spinner1);

ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_spinner_item, memilih);

adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

spinner.setAdapter(adapter);

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

@Override

public void onItemSelected(AdapterView> adapterView, View view, int position, long id) {

if (position==1){

final ImageView imageView = (ImageView) findViewById(R.id.imageView1);

pilih.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

Intent intent = new Intent(CobaActivity.this, Pilihan_Parkir_Lanjut.class);

startActivity(intent);

finish();

}

});

}

}

@Override

public void onNothingSelected(AdapterView> adapterView) {

}

});

}

class clickproses implements Button.OnClickListener {

public void onClick (View view){

String dtkategori = null;

if (radioButtonKosong.isChecked()){

dtkategori = "kosong";

}

if (radioButtonTerisi.isChecked()){

dtkategori = "terisi";

}

String str = downloadTeks("http://192.168.1.9/cobaget.php?kategori="+dtkategori);

txt.setText(str);

}

}

private InputStream OpenHttpConnection (String urlString) throws IOException {

InputStream in = null;

int response = -1;

URL url = new URL(urlString);

URLConnection conn = url.openConnection();

try {

HttpURLConnection httpConn = (HttpURLConnection) conn;

httpConn.setAllowUserInteraction(false);

httpConn.setInstanceFollowRedirects(true);

httpConn.setRequestMethod("GET");

httpConn.connect();

response = httpConn.getResponseCode();

if (response == HttpURLConnection.HTTP_OK) {

in = httpConn.getInputStream();

}

} catch (Exception ex) {

throw new IOException("Error connecting");

}

return in;

}

private String downloadTeks (String URL) {

InputStream in = null;

try {

in = OpenHttpConnection(URL);

} catch (IOException e){}

int charRead;

StringBuffer data = new StringBuffer();

String str = "";

try {

while ((charRead = in.read()) != -1){

data.append((char) charRead);

}

str = data.toString();

in.close();;

} catch (IOException e){}

return str;

}

}

这是我的数据库： MySQL数据库名称是Rizka，表名称是manarul