App Inventor and HTML/JavaScript
Note: with the new File component, which has been introduced in release nb133 on May, 18th 2014, this workaround is now obsolete. Thank you MIT!
Scott already found a solution to read a text file and display it using a trick to echo a file's
contents from App Inventor to a php server and back.
This solution here uses HTML with some JavaScript.
The example reads the text file import.txt which is stored as asset in App Inventor and displays its content in a label.
The text was created using the text generator at www.lipsum.com.
Thank you 
There is one special thing to consider for HTML documents uploaded as assets into App Inventor:
During development, you have to use the development path to the embedded HTML document.
file:///mnt/sdcard/AppInventor/assets/read.html
Before packaging the app, use the production path.
file:///android_asset/read.html
You also might be interested in the following example: How to import a multiline csv file on first run of the app.
How does this work: The webviewer loads a HTML file containing the Javascript necessary to read the text file from the assets into the webviewer document title.
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>Read File</title> </head> <body>
<script>
// the filename is hardcoded to be able to read a textfile stored as asset in App Inventor
var strFilename = "import.txt";
xmlhttp=new XMLHttpRequest();
xmlhttp.open("GET",strFilename,false);
xmlhttp.send();
xmlDoc=xmlhttp.responseText;
// print the result to the page title
window.document.title= xmlDoc;
</script>
</body> </html>
The limit to import a text file is around 2 MB (max. length of an URI).
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 2
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