Something

renderContentOn: html
	
	| titleValue isbnValue |
	html heading: 'Buch importieren' level: 3.	
	html form:[
		html text: 'Title: '.
		html textInput callback:[:val | titleValue:= val ]; value: ''.		
		html break.
		html text: 'ISBN: '.
		html textInput callback:[:val | isbnValue := val ]; value: ''.
		html submitButton text: 'importieren'; 
			callback:[
				isbnValue size < 10
					ifTrue:[self lightbox:((WAFormDialog new) addMessage: 'ISBN has to contain at least 10 characters')]
					ifFalse:[self importBookWithISBN: isbnValue].
			].
	].
	html break. 
	html break.