7

I have trouble with binding Boolean property in association classes. Property is set to true if I check checkbox (good), but is null if checbox is not checked.

I know the problem with HTML checkbox. I know why is send "_fieldName" in params, but this "_fieldName" dont set my boolean property to false.

class Person{
   String title

   List<Group> groups = new ArrayList()
   static hasMany = [groups: Groups]    
}

class Group{
   String title
   Boolean isHidden

   static belongTo = Person
}

class PersonController{

   def form = {
      def person = new Person()
      person.groups.add( new Group() )    
      return ["person": person]
   }

   def handleForm = {
      def person = new Person( params )
      println person.groups[0]
   }
}


 <g:form action="save">
    <g:textField name="title" value="${person?.title}" />
    <g:textField name="groups[0].title" value="${person?.groups[0]?.title}"/> 
    <g:checkBox name="groups[0].isHidden" value="${person?.groups[0]?.isHidden}"  />   
    <g:submitButton name="save" value="Save" />
  </g:form>

If I check checkbox:
[isHidden:on, title:a, _isHidden:]
println person.groups[0] //true

If I don check checkbox:
[title:a, _isHidden:]
println person.groups[0] //null



Thank a lot for help
Tom
I am sorry, I searched this web, but did not get actual info for my trouble.

Tomáš
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  • Some GSP code could be useful here. – Scott Warren May 30 '10 at 22:54
  • Hi Scott, I append GSP code. Thanks Tom – Tomáš May 31 '10 at 05:48
  • This bug has not been patched on the grails github repo: https://github.com/grails/grails-core/blob/master/grails-plugin-gsp/src/main/groovy/org/codehaus/groovy/grails/plugins/web/taglib/FormTagLib.groovy this was driving me crazy!! –  Mar 01 '12 at 15:09

4 Answers4

5

After much hacking it appears the answer is that grails is looking for a marker field with the name:

groups[0]._isHidden

rather than

_groups[0].isHidden

which is actually what the g:checkBox tag generates. See GrailsDataBinder.java:911 see propertyStartsWithFieldMarkerPrefix(PropertyValue pv, String fieldMarkerPrefix) for confirmation

If you are interested I've uploaded the test project for this question to gitub.com

Gareth Davis
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5

I correct checkbox tag. Thanks to gid help, now it work with association too.

from source:
http://grails.org/doc/latest/ref/Tags/checkBox.html# 

 if (value == null) value = false

out << "<input type=\"hidden\" name=\"_${name}\" /><input type=\"checkbox\" name=\"${name}\" "

if (value && checked) { out << 'checked="checked" ' }

to:

if (value == null) value = false

def begin =  name.lastIndexOf('.') +1
def tail =  name.substring( begin);
out << "<input type=\"hidden\" name=\"${name.replace(  tail, "_" + tail  )}\" /><input type=\"checkbox\" name=\"${name}\" "

if (value && checked) { out << 'checked="checked" ' }
Tomáš
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  • good stuff.. I'll see if I can create a test and patch for the grails project – Gareth Davis May 31 '10 at 18:19
  • Thanks this helps alot, i can't believe they have not fixed this yet. I had to tweak the source a little bit. But the general idea works. You need to update the name of the hidden field. – Nix Jun 05 '13 at 17:17
  • I would suggest to use a template for rendering the input tag here. That would increase your readability and maintainability. – Mohd Farid Jun 25 '14 at 18:06
1

Use the code below, 

<g:checkBox name="checkbox" value="HELLO" />

Refer :

  1. http://grails.asia/grails-checkbox-tag-example/
  2. http://grails.org/doc/latest/ref/Tags/checkBox.html
Prabhat Kashyap
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0

Set the default value of the check-box to "false", and it should solve the issue. Hope it helps.

Rijj
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