Question

我去了一个小项目，但卡住了。使用java swing时，我无法添加标签（JLabel）。代码是这样的：

JFrame frm = new JFrame("frame");
JLabel label = new JLabel("test text");
frm.add(label);

执行此操作时出错。当我把光标放在它上面时，eclipse建议我配置构建路径。我再次可以在netbeans中运行完全相同的代码。我该如何解决？

Answer 1

    <?php
$MERCHANT_KEY = "gtKFFx";
$hash_string = '';
$SALT = "eCwWELxi";
$PAYU_BASE_URL = "https://test.payu.in";
    $action = '';
$posted = array();if(!empty($_POST)) {    //print_r($_POST);
      foreach($_POST as $key => $value) { 
$posted[$key] = $value; }}
$formError = 0;
if(empty($posted['txnid'])) 
    { 
$txnid = substr(hash('sha256', mt_rand() . microtime()), 0, 20);} else { $txnid = $posted['txnid'];}
$hash = '';
$hashSequence = "key|txnid|amount|productinfo|firstname|email|udf1|udf2|udf3|udf4|udf5|udf6|udf7|udf8|udf9|udf10";
    if(empty($posted['hash']) && sizeof($posted) > 0) {  
 if( empty($posted['key']) 
|| empty($posted['txnid']) 
|| empty($posted['amount']) 
|| empty($posted['firstname']) 
|| empty($posted['email']) 
|| empty($posted['phone'])
|| empty($posted['productinfo'])
|| empty($posted['udf1']) ) { 
 $formError = 1;  } else {
$hashVarsSeq = explode('|', $hashSequence);
 foreach($hashVarsSeq as $hash_var) { 
$hash_string .= isset($posted[$hash_var]) ? $posted[$hash_var] : ''; $hash_string .= '|'; } 
$hash_string .= $SALT; $hash = strtolower(hash('sha512', $hash_string));
$action = $PAYU_BASE_URL . '/_payment'; }} 
elseif(!empty($posted['hash'])) { 
$hash = $posted['hash'];  
$action = $PAYU_BASE_URL . '/_payment';}
    ?>
    <script>
        var hash = '<?php echo $hash ?>';
        function submitPayuForm() {
          if(hash == '') {
            return;
          }
          var payuForm = document.forms.payuForm;
          payuForm.submit();
        }
      </script>
      <body onload="submitPayuForm()">
       <br/>
        <?php if($formError) { ?>
          <p style="color:red;margin-top: -120px;padding: 50px;display:none;">Please fill all mandatory fields.</p>
         <?php } ?>   
    <div class="container">
    <div class="col-md-4" id="main">
     <form action="<?php echo $action; ?>" method="post" name="payuForm" enctype="multipart/form-data" id="pay" class="myform">

          <input type="hidden" name="key" value="<?php echo $MERCHANT_KEY ?>" />
          <input type="hidden" name="hash" value="<?php echo $hash ?>"/>
          <input type="hidden" name="txnid" value="<?php echo $txnid ?>" />
     <input type="hidden" name="surl" value="https://pay-square.com/rechargesuccess-php" />   
     <input type="hidden" name="furl" value="https://pay-square.com/rechargefailure-php" />
    <div class="probod">     
     <ul class="nav nav-pills" id="navtab">
      <li class="active" ><a href="http://pay-square.com/" data-toggle="tab">Mobile</a></li>
      <li><a href="http://pay-square.com/dth" >DTH</a></li>
      <li><a href="http://pay-square.com/datacard">Data Card</a></li>
    </ul>  <br> <p style="color:red;">(* All Fields are Mandatory)</p>   
      <label for="sel1">Mobile No:</label>
      <input type="text" name="phone" class="form-control" value="<?php echo (empty($posted['phone'])) ? '' : $posted['phone']; ?>" Placeholder="Enter Your 10 digit number" required>
      <label for="sel1">Select Operator:</label>
           <select id="opt" class="form-control" title="" name="udf1" size="1">
                 <option value="">Select One</option>
                <option value="28">Airtel</option>
                <option value="1">Aircel</option>

          </select>
     <label for="sel1">Select Circle:</label>
           <select id="cir" class="form-control" title="" name="cir" size="1">
                <option value="">-Select Circle-</option>
                    <option value="23">Chennai </option>
                    <option value="1">Delhi NCR</option>
                    <option value="9">UP East</option>
                    <option value="11">UP West & Uttarakhand</option>
                    <option value="12">West Bengal</option>  
          </select>

         <label for="sel1" class="">Amount:</label>
        <input type="text" name="amount" class="form-control" value="<?php echo (empty($posted['amount'])) ? '' : $posted['amount'] ?>"Placeholder="Enter Amount" required>

    <input type="hidden" name="firstname" value="paysquare">
    <input type="hidden" name="email" value="paysquare">
    <input type="hidden" name="productinfo" value="recharge">

    <br><br>

                  <?php if(!$hash) { ?>
                <button type="submit" class="form-control" value="Submit" name="submit"/>Submit</button>
              <?php } ?>

          </form>
          </div>

    <div></div>




    success page
    <?php
    $status=$_POST["status"];
    $firstname=$_POST["firstname"];
    $txnid=$_POST["txnid"];
    $posted_hash=$_POST["hash"];
    $key=$_POST["key"];
    $productinfo=$_POST["productinfo"];
    $email=$_POST["email"];
    $amount = $_POST["amount"];
    $opt=$_SESSION["opt"];
     $salt="eCwWELxi"; 
    If (isset($_POST["additionalCharges"])) {
           $additionalCharges=$_POST["additionalCharges"];
            $retHashSeq = $additionalCharges.'|'.$salt.'|'.$status.'|||||||||'.$udf2.'|'.$udf1.'|'.$email.'|'.$firstname.'|'.$productinfo.'|'.$amount.'|'.$txnid.'|'.$key;

                      }
        else {    
            $retHashSeq = $salt.'|'.$status.'|||||||||'.$udf2.'|'.$udf1.'|'.$email.'|'.$firstname.'|'.$productinfo.'|'.$amount.'|'.$txnid.'|'.$key;
             }
             $hash = hash("sha512", $retHashSeq);
    if ($hash != $posted_hash) {
               echo "Transaction has been tampered. Please try again";
               }
           else {

     $number = $_POST["phone"];
    if(empty($opt)){
    echo"select operator";
    exit;
    }
    if(empty($number)){
    echo"enter mobile number";
    exit;
    }
    if(empty($amount)){
    echo"enter amount";
    exit;
    }
    $api_token = "myapi"; 
    $ch = curl_init();
    $timeout = 60; 
    $myurl = "https://www.pay2all.in/web-api/paynow?api_token=$api_token&provider_id=$opt&number=$number&amount=$amount";
    curl_setopt ($ch, CURLOPT_URL, $myurl);
    curl_setopt ($ch, CURLOPT_HEADER, 0);
    curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
    curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
    $file_contents = curl_exec($ch);
    curl_close($ch);
    $maindata = json_decode($file_contents, true);
    $status = $maindata['status']; 
    $message = $maindata['message']; 
    $payid = $maindata['payid']; 
    echo"Payid: $payid";
    echo"<br/>";
    echo"transaction Id: $txnid";
    echo"<br/>";
    echo"Recharge Status: $status";
    echo"<br/>";
    echo"Description is: $message";
    }exit;
    ?>

您创建的标签对象引用和要添加到框架的引用是不同的。编辑如下，然后再次检查。

CoreBrightness

Answer 2

您在JLabel中保留了Jlabel个对象引用，它应该是JLabel

JFrame frm = new JFrame("frame");
JLabel label = new JLabel("test text");         
frm.add(label);

Answer 3

Eclipse因为您的代码段中存在两个问题而抱怨：

Jlabel包中没有swing个类。有一个叫JLabel而不是。{/ li>
本地范围内没有名为jlab的变量。有一个叫做'label`而不是。

<强>替换

Jlabel label = new JLabel("test text");
frm.add(jlab);

<强>与

JLabel label = new JLabel("test text");
frm.add(label);

如何解决JLabel错误？

3 个答案: