error: Error parsing XML: not well-formed (invalid token) …?

Question

I am working on an application, with following XML. but whenI try to clean/build my project the following error occurs:

\"error: Error parsing XML: not well-formed (

Answer 1

To solve this issue, I pasted my layout into https://www.xmlvalidation.com/, which told me exactly what the error was. As was the case with other answers, my XML had < in a string.