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Calling a JavaScript function from meta tag

I am attempting to interact with a JavaScript API written by the handheld group. The JavaScript is interpreted using a bespoke browser based on chromium called Kiosk Browser. The documentation mentions that app functions can be set via HTML meta tags.

<meta http-equiv="ScannerNavigate" content="javascript:OnScan('%s', '%s', '%s');">

(1) barcode data, (2) symbology type, and (3) timestamp will be passed to a function with 3 arguments.

How would I attempt to interact with this function? I have assumed that if I write the implementation for the function with the correct signature, the arguments will be passed to it. If so, when does the function get called?

function OnScan(barcodeData, symbologyType, timestamp) {
    // Implementation here...
}

Or would I be expected to call the function without implementation?

OnScan(barcodeData, symbologyType, timestamp);

The latter seems to be unlikely. I have tried both implementations with no luck yet.

Solution

  • Found that solution for anyone else interested in working with Handheld Group devices. Simply include the <meta> tag in the <head> of the document.

    <head>
  <meta charset="utf-8">
  <meta http-equiv="ScannerNavigate" content="javascript:OnScan('%s', '%s', '%s');">

    Implement the following function in JavaScript:

    <script>
  function OnScan(barcodeData, symbologyType, timestamp) {
    alert(barcodeData);
  }
</script>

    The parameter names can be anything you like, the function is called on a successful scan with the hardware scanner and values are automatically passed to this defined function.