JavaScript

Main article: Ajax & JavaScript

Why do i get "Tapestry is undefined" error on form submit?

This client-side error is clear but can be awkward to solve. It means your browser has not been able to load the tapestry.js file properly. The question is, why? It can be due to multiple reasons, some of them below:

• First, check if 'tapestry.js' is present in the head part of your resulting HTML page.
• If you have set the tapestry.combine-scripts configuration symbol to true, Tapestry generates one single URL to retrieve all the JS files. Sometimes, this can produce long URLs that browsers are unable to retrieve. Try setting the symbol to false.
• If you have included jQuery in conjunction with Tapestry's prototype, that will cause a conflict with the '$' selector used by both. In this case, you should put jQuery on top of the stack and turn on the jQuery.noConflict mode.
• Also, if you have included a custom or third-party JS library on top of the stack that causes the JavaScript parsing to fail, then check the JavaScript syntax in that library.
• If you have used a tool to minimize your JavaScript libraries, this can lead to JavaScript syntax errors, so check if it works with all the JavaScript files unpacked.