A greeting

Create a widget that gives the appearance of a button to fields.char, works perfect, but when wanting to create a new quote in Sale Order this error appears:

TypeError: this.$(...)[0] is undefined

localhost:8069/web/webclient/js:3493

And do not let me create new quotes, I think maybe something wrong in my definition widget, but I fail to realize is, I attach the code; widget:

I put it in pastebin, since you lose the code indented pastebin.com/sXMRXJRH

thanks for the help you can give me