Going on a hunch here: if you rename the Select field to "myParameter" the Form
should be
reconstructed properly on the server side because the Select value is sent as
part of the Form POST.
Another option would be to set a hidden field in the form called "myParameter".
Again if the Form is
POSTed the "myParameter" value will be sent to the server as well.
Does this work?
Kind regards
Bob
On 30/04/2010 12:09, Bob Schellink wrote:
> Just for clarification, does the JavaScript function that captures the Select
> value do a normal Form
> submit or an Ajax request?
>
> Also what is the name of the Select field?
>
> Essentially it sounds as if the form post does not pass a parameter called
> "myParameter". You can
> confirm this by looking at the "Net" tab in Firefox's FireBug plugin.
>
> Kind regards
>
> Bob
>
> On 30/04/2010 10:05, Dipita Shah wrote:
>> I'm sending this here since my mails to the forum seem to be bouncing..
>>
>> Thanks Bob. I do actually use the request parameter from the context
>> like this:
>>
>> public class myPage extends Page {
>> Panel myPanel;
>> String myParameter;
>>
>> public onInit() {
>> myParameter= getContext().getRequestParameter("myParameter");
>> myPanel = new abcPanel(myParameter); //this is passed to the
>> constructor to figure what pararm. to use
>> myPanel.initializeFields();
>> add(myPanel);
>> } ...
>> }
>>
>> BTW, I don't have access to the Select control - it is created in the
>> form creation (in the Panel class).
>>
>> When the user changes the selection, a javascript function captures the
>> new value and passes it as a request parameter to reload the page with
>> the new parameter (which recreates the form based on this parameter.)
>>
>> This all works when just changing selections. But as soon as the submit
>> button is invoke, the request parameter on the onInit() (which seems to
>> happen before the listener is invoked) of the page is null --> I am not
>> understanding why this is null? Any ideas?
>>
>> Thanks!
>> Dipita
>>
>> -----Original Message-----
>> From: Bob Schellink [mailto:[email protected]]
>> Sent: Thursday, April 29, 2010 4:05 PM
>> Cc: Dipita Shah
>> Subject: Re: Question about onInit() and listener invokation - where to
>> initialize
>>
>> Hi Dipita,
>>
>> You are correct in that the Select field will need to be bound to its
>> request value *before* the
>> Form is initialized. The normal life cycle of Click is to bind request
>> values during the onProcess
>> event, which is *after* the Form was initialized. One way to retrieve
>> the Select request value is
>> from the Context object.
>>
>>
>> public void onInit() {
>> getContext().getRequestParameter("mySelect"); // <- mySelect will be
>> the Select field name
>> }
>>
>>
>> or if you have access to the Select, do this:
>>
>> public void onInit() {
>> Select select = new Select("mySelect");
>> select.add("option 1");
>> select.add("option 2");
>> ...
>>
>> select.bindRequestValue(); // <- will bind the select to its
>> incoming value
>> String parameter = select.getValue();
>> }
>>
>>
>> In your example I'm unsure if the Select is created inside the
>> addFieldsBasedonParameter or before.
>> I assume it is created before. So you can modify it as follows:
>>
>> public initailizeFields() {
>> select = new Select("myselect");
>> select.add("option 1");
>> ...
>> select.bindRequestValue();
>> String parameter = select.getValue();
>>
>> myForm = new Form("myForm");
>> addFieldsBasedonParameter(parameter);
>> }
>>
>>
>> In the upcoming 2.2.0 we have added helper methods to bind and validate
>> fields and forms to cater
>> for this exact scenario you describe above.
>>
>> Does that help?
>>
>> Kind regards
>>
>> Bob
>>
>> On 30/04/2010 04:03, dshah [via click] wrote:
>>> Hi,
>>> I have read all the forum questions on this topic and am unsure the
>>> correct way of implementing what I want to do:
>>>
>>> I have a page that contains a panel. In the onInit() method of the
>>> page, I create the panel and initialize a Form in that Panel.. as
>> follows:
>>>
>>> public class myPage extends Page {
>>> Panel myPanel;
>>>
>>> public onInit() {
>>> myPanel = new abcPanel(...);
>>> myPanel.initializeFields();
>>> add(myPanel);
>>> }
>>> ...
>>> }
>>>
>>> public class myPanel extends Panel {
>>> Form myForm;
>>>
>>> public myPanel(..) {
>>> //do some construction work
>>> }
>>> public initailizeFields() {
>>> myForm = new Form("myForm");
>>> addFieldsBasedonParameter(parameter) // this will populate the
>>> various fields for the form based on the parameter. The default
>>> parameter only has a small subset of the fields..
>>> }
>>> }
>>>
>>> Now my problem is that my default parameter (which is used to figure
>> out
>>> which fields should be created on the form) only have a subset of
>>> fields. Depending on this parameter, the fields could be more or
>> less..
>>> This parameter is a Select Control which is added to the form. The
>> user
>>> can select this parameter (and if the selection is changed, I reload
>> the
>>> page with the parameter) As I said some of these parameters will load
>>> more fields..
>>>
>>> Now my problem is that before the onSave (aka listener method of the
>>> form click event) is called, the onInit() is called - which recreates
>>> the Form with the default paramter (although this parameter was
>> changed
>>> when the user changed the selection...) So by the time the onSave
>>> listener is invoked, some fields that should be on the Form are not
>>> there (because the form was recreated with default parameters in the
>>> onInit() method..)
>>>
>>> What is the best way to handle this - the form fields have to be
>>> generated dynamically based on the user's selection..
>>>
>>> Any help is appreciated.
>>> Thanks!
>>> Dipita
>>>
>>>
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