App Inventor and HTML/JavaScript with Input Parameters
Note: with the extension feature, this solution is now obsolete. Thank you MIT!
Now you can use my Tools Extension instead.
Let's encrypt! I downloaded these JavaScripts from crypto-js which do the encryption and conversion to base64.
A html file accesses these scripts to supply a HMAC-SHA1 hash in base64 format back to App Inventor. The 3 files used will be downloaded
to your device on first run of the app, see also the Webprefetch File by File download example.
To test if the calculation is correct, you can compare with an Online Hash Converter. Issue 244 and Issue 553 are no issues anymore!
The HTML file encrypt.html is called from App Inventor, see screenshot below. The result is provided in the page title of the webviewer
back to App Inventor.
These are the added blocks from the Webprefetch File by File download example.
All required libraries and the HTML/JavaScript file are uploaded as assets into the app.
The HTML file encrypt.html is called from App Inventor, see screenshot below. The result is provided in the WebViewString property of the webviewer
back to App Inventor.
App Inventor,
<!DOCTYPE HTML> <html> <head> <meta name="author" content="puravidaapps.com"> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1"> <title>Encryption</title>
<script src="hmac-sha1.js"></script> <script src="enc-base64-min.js"></script>
</head> <body>
<script>
get parameter from the window.AppInventor object and split at |
var urlArray = window.AppInventor.getWebViewString().split("|");
// do the encryption
var hash = CryptoJS.HmacSHA1(urlArray[0], urlArray[1]);
print the result to the window.AppInventor object
window.AppInventor.setWebViewString(hash.toString(CryptoJS.enc.Base64));
</script>
</body> </html>
Abacus Apps you can find here and an AES Encryption and Decryption example
here.
Developing and maintaining snippets, tutorials and extensions for App Inventor takes a lot of time.
I hope it saved some of your time. If yes, then you might consider to donate a small amount!
or donate some mBTC to 
Address:
1Jd8kXLHu2Vkuhi15TWHiQm4uE9AGPYxi8
Thank you! Taifun
Download aia file for App Inventor
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