Spring Thymeleaf + Textarea - html

Question

I created form with one input text and one textarea. The input text works fine, but textarea isn't even displayed:
<div id="news" th:fragment="admin_panel">
<form method="POST" th:action="#{/addNews}" th:object="${news}" id="myform">
Tytuł:
<input type="text" th:field="*{title}"/>
<input type="submit" value="Wstaw"/>
</form>
<textarea name="news_content" rows="20" cols="80" th:field="${news.content}" form="myform">
...
</textarea>
</div>
When I delete the th:field the textarea is displayed and when I use th:value instead of th:field it's displayed too but doesn't save the written text to news.content (news.title is saved ok).
I don't have any idea... I read thymeleaf references but can't find answer, so please help good people!

Answer 1

You have to use the selected object expression *{content} AND place the textarea tag inside the form tag!
In the end its all about the generated name attribute in the resulting form. The name needs to correspond to the propertyAccessor from the selected root object th:object.
The form is processed by spring (without any thymeleaf interception).
The docs about spring integration are really good: http://www.thymeleaf.org/doc/tutorials/2.1/thymeleafspring.html
They state this:
Values for th:field attributes must be selection expressions (*{...}), which makes sense given the fact that they will be evaluated on the form-backing bean and not on the context variables (or model attributes in Spring MVC jargon).
EDIT:
Thanks to the link to the project, the fix was easy:
Thymeleaf 3.0.0.BETA03 had a bug in the textarea processor, moving to 3.0.0.RELEASE fixed this issue
Additionally I have moved the textarea inside the form element.

Answer 2

My textarea input was working fine when i was saving some data through it(in clean state when i was performing a save to DB) but in case of edit form(where my textarea input was supposed to show the prefilled description from the model property book.description) was blank, the reason for that was the th:value attribute, i changed it to the th:field attribute and it started working as expected.
<textarea class="form-control" id="description" rows="5"
name="description"
placeholder="Description" th:field="${book.description}"
required="required"></textarea>

Answer 3

You don't need the form text field. Linking the textarea with the form by the form id is sufficient.
<textarea rows="8" cols="120" name="lines" form="usrform" th:text="${message}"></textarea>
<form method="POST" enctype="multipart/form-data" th:action="#{/}" id="usrform">
<button type="submit" name="action" value="submitlines">Submit</button>
</form>
and the controller:
#RequestMapping(value="/", method=RequestMethod.POST, params="action=submitlines")
public String handleForm(
#RequestParam("lines") String input,
RedirectAttributes redirectAttributes) {
}

Answer 4

About exceptions :
SEVERE: Servlet.service() for servlet [dispatcher] in context with path [/eniupage] threw exception [Request processing failed; nested exception is org.thymeleaf.exceptions.TemplateProcessingException: Error during execution of processor 'org.thymeleaf.spring4.processor.SpringTextareaFieldTagProcessor' (template: "templates/fragments" - line 144, col 60)] with root cause
java.lang.StringIndexOutOfBoundsException: String index out of range: 0
In my form, there are text input and textarea as You see. news.title is saved ok, but news.content don't. When I replace for test these parameters (in the text input I use news.content and in the textarea there is th:field = ${news.title}) it works well too. Maybe should I use another expression instead of th:field?
News.java
package eniupage.domain;
public class News
{
private String title;
private String content;
private Date date;
public String getTitle()
{
return title;
}
public void setTitle(String title)
{
this.title = title;
}
public String getContent() {
return content;
}
public void setContent(String content)
{
this.content = content;
}
public Date getDate()
{
return date;
}
public void setDate(Date date)
{
this.date = date;
}
}
HomeController.java
package eniupage.web;
#Controller
#RequestMapping( "/" )
public class HomeController
{
#Autowired
AddNewsService addNewsService;
#RequestMapping( method = GET )
public String home( Model model )
{
model.addAttribute( "newses", addNewsService.getNewses() );
return "home";
}
#RequestMapping( value = "/addNews", method = POST )
public String addNews( News news )
{
addNewsService.addNews( news );
return "redirect:/";
}
}
AdminController.java
#Controller
#RequestMapping( "/admin" )
public class AdminController
{
#RequestMapping( method = GET )
public String admin( Model model )
{
model.addAttribute( new News() );
return "admin";
}
}
There isn't any resulting of HTML form, because it isn't even displayed in div. There are only text input and submit button.
Edited html:
<form action="#" method = "POST" th:action="#{/addNews}" th:object = "${news}" id = "myform">
Tytuł: <input type = "text" th:field = "*{title}" />
<input type = "submit" value = "Add" /></br>
<textarea rows = "20" cols = "80" th:field = "*{content}" form = "myform" >... </textarea>
</form>
I'm using thymeleaf 3.0. Maybe this is the reason?
In reference I read :
The th:field attribute behaves differently depending on whether it is attached to an , or tag (and also depending on the specific type of tag).
But I can't find what is this difference between using th:field in input and textarea.