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PHP generates an Android client that scans the QR code that can be logged in, android client_PHP tutorial
PHP generates an Android client that scans the QR code that can be logged in, android client_PHP tutorial
Jul 12, 2016 am 08:51 AM
php generates a QR code that the Android client can scan to log in, android client
The example in this article shares with you a php web page that generates a QR code, and the Android client scans it to log in. The specific code is for your reference. The specific content is as follows
Used the ZXing open source library with code scanning function on Github, and used the network API to generate QR code images through random numbers. The whole process went through three steps:
1. The PHP webpage generates a QR code and the corresponding random number is stored in the database;
2. Scan the code with the Android client and save the username to the location corresponding to the random number;
3. Every once in a while, PHP polls the database through Ajax to determine whether it is empty. If not, it will jump to the web page.
Specific code:
1. Generate a QR code image through random numbers and execute the main page of the polling operation command?
<html>
<head>
<title>qrlogin</title>
<meta charset="UTF-8"/>
</head>
<body>
<?php
/**
* @author Cenquanyu
* @version 2016年5月12日
*
*/
require 'mysql_connect.php';
$randnumber = "";
for($i=0;$i<8;$i++){
$randnumber.=rand(0,9);
}
//將生成的隨機數(shù)保存至數(shù)據(jù)庫
mysql_query("insert into login_data (randnumber) values ('$randnumber')")
?>
<img src="http://qr.liantu.com/api.php?text=<?php echo $randnumber;?>" width="300px"/>
<input hidden="hidden" type="text" name="randnumber" id="randnumber"value="<?php echo $randnumber;?>"/>
</body>
<script>
xmlHttpRequest.onreadystatechange = function(){
if(xmlHttpRequest.status == 200 && xmlHttpRequest.readyState ==4){
result = xmlHttp.responseText;
if(result==true){//username不為空則跳轉(zhuǎn)頁面
window.location.href='welcome.php';
}
}
}
}
function polling(){
//執(zhí)行輪詢操作
var xmlHttpRequest;
if(window.XMLHttpRequest){
xmlHttpRequest = new XMLHttpRequest();
}
else{
xmlHttpRequest = new ActiveXObject("Microsoft.XMLHTTP");
}
randnumber = document.getElementById('randnumber').value;
xmlHttpRequest.open("GET","polling.php?randnumber="+ randnumber,true);
xmlHttpRequest.send();
}
setInterval("polling()",1000);
</script>
</html>
2. Database connection page
<?php
/**
* 數(shù)據(jù)庫連接文件
* @author Cenquanyu
* @version 2016年5月12日
*
*/
$con = mysql_connect("localhost","root","") or die(mysql_error());
mysql_select_db("qr_login");
?>
3. The page that performs polling operation, jump if username is not empty
<?php
/**
* @author Cenquanyu
* @version 2016年5月12日
* 執(zhí)行輪詢操作，查詢隨機數(shù)在數(shù)據(jù)庫中的相應(yīng)位置的username字段為不為空
* 為空，則返回false,頁面不跳轉(zhuǎn)
* 不為空，則說明有用戶進(jìn)行了該二維碼的掃碼登錄，頁面進(jìn)行跳轉(zhuǎn)
*/
require 'mysql_connect.php';
$randnumber = $_GET['randnumber'];
$result = mysql_query("select * from login_data where randnumber='$randnumber'");
$row = mysql_fetch_array($result);
if($row['username']!="")
echo "true";
else
echo "false";
?>
4. Customized API to save the client’s username
<?php
/**
* @author Cenquanyu
* @version 2016年5月12日
* 自定義API用于Android客戶端掃碼登錄，將客戶端的username保存至二維碼對應(yīng)的隨機數(shù)在數(shù)據(jù)庫中的相應(yīng)位置。
* 參數(shù)：username，randnumber
* 無返回值
*/
$randnumber = $_GET('randnumber');
$username = $_GET('username');
require 'mysql_connect.php';
mysql_query("update qr_login set username='$username' where randnumber= '$randnumber'");
?>
5. Activity for Android client to perform QR code scanning operation
package com.Cenquanyu.qrlogin;
import com.Cenquanyu.qrlogin.R;
import com.zxing.activity.CaptureActivity;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Paint.Cap;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
/**
* @author Cenquanyu
* @version 2016年5月12日
*
*/
public class MainActivity extends Activity implements OnClickListener {
private Button btnScan;
private EditText etUsername;
private static final String WEB_URL = "http://172.31.19.202/QRLogin/";//改成PC端相應(yīng)地址
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnScan = (Button) findViewById(R.id.btnScan);
btnScan.setOnClickListener(this);
etUsername = (EditText) findViewById(R.id.etUsername);
}
@Override
public void onClick(View v) {
// 掃碼操作
Intent intent = new Intent(this, CaptureActivity.class);
startActivityForResult(intent, 0);//返回結(jié)果
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK) {
String randnumber = data.getExtras().getString("result");//客戶端掃碼后返回掃描結(jié)果，將二維碼對應(yīng)的隨機數(shù)取出
String username = etUsername.getText().toString();
String url = WEB_URL + "saveUsername.php?randnumber=" + randnumber
+ "&username=" + username;
HttpUtils.login(url);//訪問url
}
}
}
6. Network request class
package com.Cenquanyu.qrlogin;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
public class HttpUtils{
public static void login(final String url){
new Thread(new Runnable() {
@Override
public void run() {
HttpURLConnection connection;
try {
connection = (HttpURLConnection) new URL(url).openConnection();
connection.setRequestMethod("GET");
connection.getInputStream();
} catch (Exception e) {
e.printStackTrace();
}
}
}).start();
}
}
The above is the entire content of this article, I hope it will be helpful to everyone’s study.
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