documentation/IS4C/developer/api/requestinfo.html
<html>
<head>
<title>Requesting Information</title>
</head>
<body>
<div style="text-align:center;">
<h1>Requesting Information from the User</h1>
<!--
13Aug13 AT Doc first written
-->
<br />as of: August 13, 2013
</div>
<p>
If you want to prompt the cashier to enter some text, you
can use the built-in <i>requestInfo.php</i> gui-module rather
than writing a separate page. This is well-suited for cases
where you simply want to show a text entry box and get the
result. To use this functionality, pass the name of an
appropriate class to requestInfo.php as the URL parameter
<i>class</i>. The class does not have to inherit from any
particular base class; it merely has to provide the methods
and properties that requestInfo.php needs (i.e., <i>duck typing</i>).
This structure lets you attach an information request to another
class.
</p>
<blockquote>
static string <b>requestInfoHeader</b><br />
static string <b>requestInfoMsg</b><br />
static mixed <b>requestInfoCallback</b>(string $info)<br />
</blockquote>
<p>
The strings properties are prompts displayed for the cashier.
<b>requestInfoHeader</b> appears above the input box;
<b>requestInfoMsg</b> appears below the input box. When the cashier
enters information, that string is passed to <b>requestInfoCallback</b>.
If the string is not a valid entry, return boolean False to prompt
the cashier to re-enter. If the string is valid, do whatever processing
is necessary then return a URL indicating which page to go to next.
If you want to return to the main POS screen, returning boolean True
will be interpretted as that URL.
</p>
<p>
<b>Example</b>: Add member's phone number to the transaction
<pre>
class GetMemPhone extends Parser {
function check($str){
if ($str == 'GETPH') return True;
else return False;
}
function parse($str){
$ret = $this->default_json();
// redirect to the prompt page
$ret['main_frame'] = MiscLib::base_url().'gui-modules/requestInfo.php?class=GetMemPhone';
return $ret;
}
public static $requestInfoHeader = 'member phone #';
public static $requestInfoMsg = 'type phone number XXX-XXX-XXXX';
public static function requestInfoCallback($info){
// if the entry is valid, add a comment to
// the transaction
if (preg_match('/^\d\d\d-\d\d\d-\d\d\d\d$/',trim($info)) == 1){
TransRecord::addcomment('PH: '.trim($info));
return True;
}
else
return False;
}
}
</pre>
</p>
</body>
</html>