how to handle clear input for custom FormComponents
Hi all, I've developed a custom FormComponent (by subclassing FormComponentPanel) to act as a reference from one object to another (eg a Customer to an Address), but am having problems figuring out how to handle clear input (ie, if the user hits the cancel button on the form). To explain a little further, the FormComponent is called EntityLink, and renders the reference (eg the Customer's homeAddress) a hyperlink. I have a button on the EntityLink panel allowing the user to perform a search for other objects of the correct type, and then select it. Doing this updates the EntityLink component, with a pending value (ie of the new homeAddress). If the user hits the OK button, then the pending value is copied over to the domain object (ie to the Customer's actual homeAddress property). In the cancel button's onSubmit() method I'm calling getForm().clearInput(), which seems to use a visitor to call clearInput() on all child FormComponent's. The FormComponent's clearInput() method seems only to set the rawInput to a constant (NO_RAW_INPUT), which looks like it's a magic value of some kind when the form component is actually rendered - all rather low level. I think what I'd like is to eagerly capture this clearInput so that I can reset my EntityLink's hyperlink back to the original value and discard the pending value. However, clearInput() is unfortunately marked as final so there doesn't seem to be any easy way to capture this. Looking at other implementations of FormComponentPanel (eg DateTimeField) they are really very little other than wrappers around simple FormComponents, so they don't offer any real clues. Can anyone help me here, then? Thanks Dan -- Dan Haywood consultant, mentor, developer, author agile, ddd, oo, java, .net, sybase MA, MBCS, CITP, CEng /mail: /d...@haywood-associates.co.uk mailto:d...@haywood-associates.co.uk /phone: /+44 (0)7961 144286 /book: /Domain Driven Design using Naked Objects http://pragprog.com/titles/dhnako /blog: /http://danhaywood.com /linked in: /http://uk.linkedin.com/in/dkhaywood /twitter: /http://twitter.com/dkhaywood /sybase: /http://sybtraining.co.uk - To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org
RE: how to handle clear input for custom FormComponents
You shouldn't be committing your changes to the actual domain object until the form is submitted (your ok button). Jeremy Thomerson http://www.wickettraining.com -- sent from a wireless device -Original Message- From: Dan Haywood dkhayw...@gmail.com Sent: Monday, April 19, 2010 5:53 AM To: users@wicket.apache.org Subject: how to handle clear input for custom FormComponents Hi all, I've developed a custom FormComponent (by subclassing FormComponentPanel) to act as a reference from one object to another (eg a Customer to an Address), but am having problems figuring out how to handle clear input (ie, if the user hits the cancel button on the form). To explain a little further, the FormComponent is called EntityLink, and renders the reference (eg the Customer's homeAddress) a hyperlink. I have a button on the EntityLink panel allowing the user to perform a search for other objects of the correct type, and then select it. Doing this updates the EntityLink component, with a pending value (ie of the new homeAddress). If the user hits the OK button, then the pending value is copied over to the domain object (ie to the Customer's actual homeAddress property). In the cancel button's onSubmit() method I'm calling getForm().clearInput(), which seems to use a visitor to call clearInput() on all child FormComponent's. The FormComponent's clearInput() method seems only to set the rawInput to a constant (NO_RAW_INPUT), which looks like it's a magic value of some kind when the form component is actually rendered - all rather low level. I think what I'd like is to eagerly capture this clearInput so that I can reset my EntityLink's hyperlink back to the original value and discard the pending value. However, clearInput() is unfortunately marked as final so there doesn't seem to be any easy way to capture this. Looking at other implementations of FormComponentPanel (eg DateTimeField) they are really very little other than wrappers around simple FormComponents, so they don't offer any real clues. Can anyone help me here, then? Thanks Dan -- Dan Haywood consultant, mentor, developer, author agile, ddd, oo, java, .net, sybase MA, MBCS, CITP, CEng mail: d...@haywood-associates.co.uk phone: +44 (0)7961 144286 book: Domain Driven Design using Naked Objects blog: http://danhaywood.com linked in: http://uk.linkedin.com/in/dkhaywood twitter: http://twitter.com/dkhaywood sybase: http://sybtraining.co.uk
Re: how to handle clear input for custom FormComponents
I found a way to make this work (though I worry the solution might be a little fragile). Basically, I'm overriding getInputAsArray() in my wrapper EntityLink, delegating to a hidden text field; then, in onBeforeRender() I check if there is input, and if not then infer that clearInput must've been called on and so zap the value of the hidden text field. If anyone cares to look at the code, it's on sourceforge: http://wicketobjects.svn.sourceforge.net/viewvc/wicketobjects/trunk/main/viewer/src/main/java/org/starobjects/wicket/viewer/components/entitylink/EntityLink.java?revision=78view=markup Thanks anyway Dan Dan Haywood consultant, mentor, developer, author agile, ddd, oo, java, .net, sybase MA, MBCS, CITP, CEng /mail: /d...@haywood-associates.co.uk mailto:d...@haywood-associates.co.uk /phone: /+44 (0)7961 144286 /book: /Domain Driven Design using Naked Objects http://pragprog.com/titles/dhnako /blog: /http://danhaywood.com /linked in: /http://uk.linkedin.com/in/dkhaywood /twitter: /http://twitter.com/dkhaywood /sybase: /http://sybtraining.co.uk On 19/04/2010 13:08, Jeremy Thomerson wrote: You shouldn't be committing your changes to the actual domain object until the form is submitted (your ok button). Jeremy Thomerson http://www.wickettraining.com -- sent from a wireless device From: Dan Haywood dkhayw...@gmail.com Sent: Monday, April 19, 2010 5:53 AM To: users@wicket.apache.org Subject: how to handle clear input for custom FormComponents Hi all, I've developed a custom FormComponent (by subclassing FormComponentPanel) to act as a reference from one object to another (eg a Customer to an Address), but am having problems figuring out how to handle clear input (ie, if the user hits the cancel button on the form). To explain a little further, the FormComponent is called EntityLink, and renders the reference (eg the Customer's homeAddress) a hyperlink. I have a button on the EntityLink panel allowing the user to perform a search for other objects of the correct type, and then select it. Doing this updates the EntityLink component, with a pending value (ie of the new homeAddress). If the user hits the OK button, then the pending value is copied over to the domain object (ie to the Customer's actual homeAddress property). In the cancel button's onSubmit() method I'm calling getForm().clearInput(), which seems to use a visitor to call clearInput() on all child FormComponent's. The FormComponent's clearInput() method seems only to set the rawInput to a constant (NO_RAW_INPUT), which looks like it's a magic value of some kind when the form component is actually rendered - all rather low level. I think what I'd like is to eagerly capture this clearInput so that I can reset my EntityLink's hyperlink back to the original value and discard the pending value. However, clearInput() is unfortunately marked as final so there doesn't seem to be any easy way to capture this. Looking at other implementations of FormComponentPanel (eg DateTimeField) they are really very little other than wrappers around simple FormComponents, so they don't offer any real clues. Can anyone help me here, then? Thanks Dan -- Dan Haywood consultant, mentor, developer, author agile, ddd, oo, java, .net, sybase MA, MBCS, CITP, CEng /mail: /d...@haywood-associates.co.uk mailto:d...@haywood-associates.co.uk /phone: /+44 (0)7961 144286 /book: /Domain Driven Design using Naked Objects http://pragprog.com/titles/dhnako /blog: /http://danhaywood.com /linked in: /http://uk.linkedin.com/in/dkhaywood /twitter: /http://twitter.com/dkhaywood /sybase: /http://sybtraining.co.uk - To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org
