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Posted to users@tapestry.apache.org by Jim Downing <oj...@cam.ac.uk> on 2007/01/09 15:46:38 UTC
Newbie help with For and TextField components
Hi,
I'm trying to get some simple list editing working using For and
TextField but not having much luck.
Home.html: -
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>Example app</title>
</head>
<body jwcid="@Body">
<h1>Hello world!</h1>
<form jwcid="@Form" success="listener:submit">List
of names:
<div jwcid="@For" source="ognl:names" value="ognl:name" index="ognl:idx">
<p><span jwcid="@Insert" value="ognl:idx">1</span> <input
jwcid="@TextField" value="ognl:name" /></p>
</div>
<input type="submit" jwcid="@Submit" listener="listener:add" value="Add" />
<input type="submit" jwcid="@Submit" value="Update" /></form>
</body>
</html>
Home.java
public abstract class Home extends BasePage implements
PageBeginRenderListener {
private static final Logger LOG = Logger.getLogger(Home.class);
public void pageBeginRender(PageEvent event) {
LOG.info("Begin render. Rewind? " +
getRequestCycle().isRewinding());
if(getNames()== null) {
LOG.info("Initializing names list");
setNames(new ArrayList<String>());
}
}
public void submit() {
LOG.info("Submitted. List is: " + getNames());
}
public void add() {
LOG.info("Adding a blank name to "+ getNames());
List<String> nms = getNames();
nms.add("");
setNames(nms);
}
public abstract List<String> getNames();
public abstract void setNames(List<String> nms);
public abstract String getName();
public abstract int getIdx();
}
When I click the "Add" button I get: -
9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? true
9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names list
9627423 [btpool0-3] INFO com.example.pages.Home - Adding a blank name
to []
9627424 [btpool0-3] INFO com.example.pages.Home - Submitted. List is:
[ ---- ]
9627424 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? false
Then changing the value in the form input and clicking submit produces
this: -
9638858 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? true
9638858 [btpool0-3] INFO com.example.pages.Home - Initializing names list
9638859 [btpool0-3] INFO com.example.pages.Home - Submitted. List is: []
9638859 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? false
I'm puzzled - why hasn't the list been populated from the TextFields in
the For loop?
Any pointers gratefully received.
cheers,
jim
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Re: Newbie help with For and TextField components
Posted by Daniel Tabuenca <dt...@gmail.com>.
I don't get it. What are you trying to do? You aren't persisting your
list anywhere.... so at each render or rewind your lists starts off
null..... so by the time it gets to the @For loop the @For loop has
nothing to iterate over. Am I missing something?
On 1/9/07, Jim Downing <oj...@cam.ac.uk> wrote:
> Hi,
>
> I'm trying to get some simple list editing working using For and
> TextField but not having much luck.
>
> Home.html: -
>
> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
> <head>
> <title>Example app</title>
> </head>
> <body jwcid="@Body">
> <h1>Hello world!</h1>
> <form jwcid="@Form" success="listener:submit">List
> of names:
> <div jwcid="@For" source="ognl:names" value="ognl:name" index="ognl:idx">
> <p><span jwcid="@Insert" value="ognl:idx">1</span> <input
> jwcid="@TextField" value="ognl:name" /></p>
> </div>
> <input type="submit" jwcid="@Submit" listener="listener:add" value="Add" />
> <input type="submit" jwcid="@Submit" value="Update" /></form>
> </body>
> </html>
>
> Home.java
>
> public abstract class Home extends BasePage implements
> PageBeginRenderListener {
>
> private static final Logger LOG = Logger.getLogger(Home.class);
>
> public void pageBeginRender(PageEvent event) {
> LOG.info("Begin render. Rewind? " +
> getRequestCycle().isRewinding());
> if(getNames()== null) {
> LOG.info("Initializing names list");
> setNames(new ArrayList<String>());
> }
> }
>
> public void submit() {
> LOG.info("Submitted. List is: " + getNames());
> }
>
> public void add() {
> LOG.info("Adding a blank name to "+ getNames());
> List<String> nms = getNames();
> nms.add("");
> setNames(nms);
> }
>
> public abstract List<String> getNames();
>
> public abstract void setNames(List<String> nms);
>
> public abstract String getName();
>
> public abstract int getIdx();
> }
>
> When I click the "Add" button I get: -
>
> 9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? true
> 9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names list
> 9627423 [btpool0-3] INFO com.example.pages.Home - Adding a blank name
> to []
> 9627424 [btpool0-3] INFO com.example.pages.Home - Submitted. List is:
> [ ---- ]
> 9627424 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? false
>
> Then changing the value in the form input and clicking submit produces
> this: -
>
> 9638858 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? true
> 9638858 [btpool0-3] INFO com.example.pages.Home - Initializing names list
> 9638859 [btpool0-3] INFO com.example.pages.Home - Submitted. List is: []
> 9638859 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? false
>
> I'm puzzled - why hasn't the list been populated from the TextFields in
> the For loop?
>
> Any pointers gratefully received.
>
> cheers,
> jim
>
>
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> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
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>
>
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Re: Newbie help with For and TextField components
Posted by Jim Downing <oj...@cam.ac.uk>.
Hi Daniel,
thanks very much for this, it makes things much clearer (best
explanation of it I've seen by a long chalk!).
I'll take your advice and create a holder object for my string that uses
a UUID to identify the strings.
Thanks!
jim
Daniel Tabuenca wrote:
>> Eventually I'm going to be saving the values in RDF - the values won't
>> have a persistent key, they're just literal values. I'm also keen to
>> avoid using any session persistence but will do if it's necessary. Can
>> tapestry deal with simple values that don't have identity in this way?
>
> To understand this you need to know what that key is really used for.....
>
> Say I have a Person Object...
>
> public class Person(){
>
> public String name;
> public String id;
> }
>
> and two person Object sin a list;
>
> Person bob;
> Person alice;
> List<Person> personList;
>
> bob.setName("Bob");
> bob.setId("1");
>
> alice.setName("Alice");
> alice.setId("2");
>
> personList.add(bob);
> personList.add(alice);
>
>
>
> Now... when if I set my keyExpression to be person.id when tapestry
> renders out the form it stores a hidden field with the ids in order..
> in this case it would have "1" and "2". Why is this important? Well
> you have to understand what happens during a rewind. It is nothing
> magical really and the simplistic way to explain is that your page
> just renders out again but with the form bindings reversed.... so in
> your case....
>
> <input jwcid="@TextField" value="ognl:name" />
>
> when it gets to that input field... instead of reading the "value"
> parameter with getName() it simply writes that paremeter with
> setName().
>
>
> so say I got the page and it has a list of my current users....
>
> * [ BOB ]
> * [ALICE ]
>
> now I want to change Bob's name to Robert so I edit.....
>
> * [ROBERT]
> * [ALICE]
>
> and hit submit..
>
> What happens if while I was changing the name on the form.. someone
> somehow change the original person list so that the names are
> backwards so the objects are { alice, bob}. If tapestry allowed it
> this would be bad! Because you meant to change Bob's name but as far
> as Tapestry is concerned you just instructed it to set the name on the
> first item on the list to "Robert". And if the order on the list was
> somehow changed it's your Alice object that will get it's name change.
>
> This is why tapestry stores extra information in the hidden field.
> What it does, is before actually calling setName() it will check that
> your keyExpression submitted with the form matches the keyExpression
> of the object from the list. If the list got changed this will be
> different and tapestry will detect this and throw you an exception so
> you don't accidentally delete or modify th wrong object.
>
> Of course... if you don't have a real key you can either make one up.
> Or if your oject converts automatically to a string tapestry will just
> store that in the hidden fields. Of course, if you don't care about
> what I just described or you know for certain that nobody will modify
> the list, you could set keyExpression to something constant so it
> always matches no matter what.
>
> I hope this explenation was useful. The whole rewind idea seemed
> magical to me until someone explained it to me like this.
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Re: Newbie help with For and TextField components
Posted by Daniel Tabuenca <dt...@gmail.com>.
>Eventually I'm going to be saving the values in RDF - the values won't
>have a persistent key, they're just literal values. I'm also keen to
>avoid using any session persistence but will do if it's necessary. Can
>tapestry deal with simple values that don't have identity in this way?
To understand this you need to know what that key is really used for.....
Say I have a Person Object...
public class Person(){
public String name;
public String id;
}
and two person Object sin a list;
Person bob;
Person alice;
List<Person> personList;
bob.setName("Bob");
bob.setId("1");
alice.setName("Alice");
alice.setId("2");
personList.add(bob);
personList.add(alice);
Now... when if I set my keyExpression to be person.id when tapestry
renders out the form it stores a hidden field with the ids in order..
in this case it would have "1" and "2". Why is this important? Well
you have to understand what happens during a rewind. It is nothing
magical really and the simplistic way to explain is that your page
just renders out again but with the form bindings reversed.... so in
your case....
<input jwcid="@TextField" value="ognl:name" />
when it gets to that input field... instead of reading the "value"
parameter with getName() it simply writes that paremeter with
setName().
so say I got the page and it has a list of my current users....
* [ BOB ]
* [ALICE ]
now I want to change Bob's name to Robert so I edit.....
* [ROBERT]
* [ALICE]
and hit submit..
What happens if while I was changing the name on the form.. someone
somehow change the original person list so that the names are
backwards so the objects are { alice, bob}. If tapestry allowed it
this would be bad! Because you meant to change Bob's name but as far
as Tapestry is concerned you just instructed it to set the name on the
first item on the list to "Robert". And if the order on the list was
somehow changed it's your Alice object that will get it's name change.
This is why tapestry stores extra information in the hidden field.
What it does, is before actually calling setName() it will check that
your keyExpression submitted with the form matches the keyExpression
of the object from the list. If the list got changed this will be
different and tapestry will detect this and throw you an exception so
you don't accidentally delete or modify th wrong object.
Of course... if you don't have a real key you can either make one up.
Or if your oject converts automatically to a string tapestry will just
store that in the hidden fields. Of course, if you don't care about
what I just described or you know for certain that nobody will modify
the list, you could set keyExpression to something constant so it
always matches no matter what.
I hope this explenation was useful. The whole rewind idea seemed
magical to me until someone explained it to me like this.
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Re: Newbie help with For and TextField components
Posted by Daniel Tabuenca <dt...@gmail.com>.
Well it's because you are using strings directly. Here's what the
equivalent of what is going on in JAVA:
List<String> names = NAMES;
for( String name : names ){
name = " NEW VALUE FROM INPUT FIELD";
// but strings are immutable so name has a new string reference and
does not modify
// the one that is part of the list.
}
What happens is your new name is stored only in the "name" property
and never makes it back to your list.... try printing out getName()
and you will see that it is probably set to your last name on the
list.....
On 1/10/07, Jim Downing <oj...@cam.ac.uk> wrote:
> Hi Daniel,
>
> thanks for the help!
>
> Daniel Tabuenca wrote:
> > The Chart example the plotValues property is persisted:
> >
> > <page-specification
> > class="org.apache.tapestry.workbench.chart.ChartPage">
> >
> > <property name="plotValues" persist="session"/>
> >
> > .......
> >
> >
> > I am assuming you are not persisting since from your logs:
> >
> > 9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
> > Rewind? true
> > 9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names
> > list
>
> It's true, I wasn't persisting them. To be ultra-simplistic I've done
> this by storing them back in a static field: -
>
> Home.java:
> ...
> public static List<String> NAMES = new ArrayList<String>();
> public void pageBeginRender(PageEvent event) {
> LOG.info("Begin render. Rewind? " +
> getRequestCycle().isRewinding() +". Names: "+ getNames());
> LOG.info("Initializing names list to "+ NAMES);
> setNames(NAMES);
> }
>
> public void submit() {
> LOG.info("Submitted. List is: " + getNames());
> NAMES = getNames();
> }
>
> public void add() {
> LOG.info("Adding a blank name to " + getNames());
> List<String> nms = getNames();
> nms.add("");
> setNames(nms);
> }
> ...
>
>
> Unfortunately that doesn't seem to be at the heart of the problem - the
> list now grows as desired when the 'add' listener is called, but the
> values in the list aren't changed. It looks like the form values aren't
> correctly set after the rewind, e.g. in the log excerpt below I'd be
> expecting to see the (non-blank) form values in the message at the
> highlighted point: -
>
> INFO com.example.pages.Home - Begin render. Rewind? true. Names: null
> INFO com.example.pages.Home - Initializing names list to [, , ]
> --> INFO com.example.pages.Home - Submitted. List is: [, , ] <--
> INFO com.example.pages.Home - Begin render. Rewind? false. Names: [, , ]
> INFO com.example.pages.Home - Initializing names list to [, , ]
>
> Eventually I'm going to be saving the values in RDF - the values won't
> have a persistent key, they're just literal values. I'm also keen to
> avoid using any session persistence but will do if it's necessary. Can
> tapestry deal with simple values that don't have identity in this way?
>
> Thanks,
>
> jim
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>
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Re: Newbie help with For and TextField components
Posted by Jim Downing <oj...@cam.ac.uk>.
Hi Daniel,
thanks for the help!
Daniel Tabuenca wrote:
> The Chart example the plotValues property is persisted:
>
> <page-specification
> class="org.apache.tapestry.workbench.chart.ChartPage">
>
> <property name="plotValues" persist="session"/>
>
> .......
>
>
> I am assuming you are not persisting since from your logs:
>
> 9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? true
> 9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names
> list
It's true, I wasn't persisting them. To be ultra-simplistic I've done
this by storing them back in a static field: -
Home.java:
...
public static List<String> NAMES = new ArrayList<String>();
public void pageBeginRender(PageEvent event) {
LOG.info("Begin render. Rewind? " +
getRequestCycle().isRewinding() +". Names: "+ getNames());
LOG.info("Initializing names list to "+ NAMES);
setNames(NAMES);
}
public void submit() {
LOG.info("Submitted. List is: " + getNames());
NAMES = getNames();
}
public void add() {
LOG.info("Adding a blank name to " + getNames());
List<String> nms = getNames();
nms.add("");
setNames(nms);
}
...
Unfortunately that doesn't seem to be at the heart of the problem - the
list now grows as desired when the 'add' listener is called, but the
values in the list aren't changed. It looks like the form values aren't
correctly set after the rewind, e.g. in the log excerpt below I'd be
expecting to see the (non-blank) form values in the message at the
highlighted point: -
INFO com.example.pages.Home - Begin render. Rewind? true. Names: null
INFO com.example.pages.Home - Initializing names list to [, , ]
--> INFO com.example.pages.Home - Submitted. List is: [, , ] <--
INFO com.example.pages.Home - Begin render. Rewind? false. Names: [, , ]
INFO com.example.pages.Home - Initializing names list to [, , ]
Eventually I'm going to be saving the values in RDF - the values won't
have a persistent key, they're just literal values. I'm also keen to
avoid using any session persistence but will do if it's necessary. Can
tapestry deal with simple values that don't have identity in this way?
Thanks,
jim
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Re: Newbie help with For and TextField components
Posted by Daniel Tabuenca <dt...@gmail.com>.
The Chart example the plotValues property is persisted:
<page-specification class="org.apache.tapestry.workbench.chart.ChartPage">
<property name="plotValues" persist="session"/>
.......
I am assuming you are not persisting since from your logs:
9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? true
9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names list
The list gest reinitialized on each request.
I think you may be misunderstanding the @For loop. @For inside a form
will not create a List or populate it for you. @For works with an
existing list and in your case the existing list is a new list on each
beginRender. @For then iterates over an empty list which means nothing
inside it will ever get executed (all your form input fields never get
rewound). The keyExpression is used only to verify that the list that
you are working with has not changed since you rendered the page. In
your case it HAS! When you rendered the page originally your list had
a blank name in it. On the rewind it has no elements. Maybe tapestry
should be smarter and throw an error when the size of the list doesn't
match the size from when it was rendered.
On 1/10/07, Jim Downing <oj...@cam.ac.uk> wrote:
> Hi Jesse,
>
> Jesse Kuhnert wrote:
> > I think the problem with this approach is that the For component has
> > no way of uniquely identifying your list values.
> >
> > I would try using the keyExpression or converter parameters of the For
> > component to do this instead.
> > http://tapestry.apache.org/tapestry4.1/components/general/for.html
>
> Thanks for the pointers, but I'm still having problems, using either a
> custom converter or a keyExpression (using "toString()"). As I
> understand it either of these methods rely on there being a single
> reference to the object that doesn't change between requests. This
> obviously doesn't exist for value objects.
>
> What I'm finding confusing is that this looks to me just like the
> example in the charts pane of the tapestry workbench demo; there a list
> of PlotValues is edited without keyExpresssion or a converter. Why is
> this different?
>
> Would a reasonable hack be to bind the value of the text field input to
> a property with a concrete setter that used the @For index to build the
> new list items manually?
>
> Thanks,
>
> jim
>
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> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>
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Re: Newbie help with For and TextField components
Posted by Jim Downing <oj...@cam.ac.uk>.
Hi Jesse,
Jesse Kuhnert wrote:
> I think the problem with this approach is that the For component has
> no way of uniquely identifying your list values.
>
> I would try using the keyExpression or converter parameters of the For
> component to do this instead.
> http://tapestry.apache.org/tapestry4.1/components/general/for.html
Thanks for the pointers, but I'm still having problems, using either a
custom converter or a keyExpression (using "toString()"). As I
understand it either of these methods rely on there being a single
reference to the object that doesn't change between requests. This
obviously doesn't exist for value objects.
What I'm finding confusing is that this looks to me just like the
example in the charts pane of the tapestry workbench demo; there a list
of PlotValues is edited without keyExpresssion or a converter. Why is
this different?
Would a reasonable hack be to bind the value of the text field input to
a property with a concrete setter that used the @For index to build the
new list items manually?
Thanks,
jim
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Re: Newbie help with For and TextField components
Posted by Jesse Kuhnert <jk...@gmail.com>.
I think the problem with this approach is that the For component has
no way of uniquely identifying your list values.
I would try using the keyExpression or converter parameters of the For
component to do this instead.
http://tapestry.apache.org/tapestry4.1/components/general/for.html
On 1/9/07, Jim Downing <oj...@cam.ac.uk> wrote:
> Hi,
>
> I'm trying to get some simple list editing working using For and
> TextField but not having much luck.
>
> Home.html: -
>
> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
> <head>
> <title>Example app</title>
> </head>
> <body jwcid="@Body">
> <h1>Hello world!</h1>
> <form jwcid="@Form" success="listener:submit">List
> of names:
> <div jwcid="@For" source="ognl:names" value="ognl:name" index="ognl:idx">
> <p><span jwcid="@Insert" value="ognl:idx">1</span> <input
> jwcid="@TextField" value="ognl:name" /></p>
> </div>
> <input type="submit" jwcid="@Submit" listener="listener:add" value="Add" />
> <input type="submit" jwcid="@Submit" value="Update" /></form>
> </body>
> </html>
>
> Home.java
>
> public abstract class Home extends BasePage implements
> PageBeginRenderListener {
>
> private static final Logger LOG = Logger.getLogger(Home.class);
>
> public void pageBeginRender(PageEvent event) {
> LOG.info("Begin render. Rewind? " +
> getRequestCycle().isRewinding());
> if(getNames()== null) {
> LOG.info("Initializing names list");
> setNames(new ArrayList<String>());
> }
> }
>
> public void submit() {
> LOG.info("Submitted. List is: " + getNames());
> }
>
> public void add() {
> LOG.info("Adding a blank name to "+ getNames());
> List<String> nms = getNames();
> nms.add("");
> setNames(nms);
> }
>
> public abstract List<String> getNames();
>
> public abstract void setNames(List<String> nms);
>
> public abstract String getName();
>
> public abstract int getIdx();
> }
>
> When I click the "Add" button I get: -
>
> 9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? true
> 9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names list
> 9627423 [btpool0-3] INFO com.example.pages.Home - Adding a blank name
> to []
> 9627424 [btpool0-3] INFO com.example.pages.Home - Submitted. List is:
> [ ---- ]
> 9627424 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? false
>
> Then changing the value in the form input and clicking submit produces
> this: -
>
> 9638858 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? true
> 9638858 [btpool0-3] INFO com.example.pages.Home - Initializing names list
> 9638859 [btpool0-3] INFO com.example.pages.Home - Submitted. List is: []
> 9638859 [btpool0-3] INFO com.example.pages.Home - Begin render.
> Rewind? false
>
> I'm puzzled - why hasn't the list been populated from the TextFields in
> the For loop?
>
> Any pointers gratefully received.
>
> cheers,
> jim
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>
--
Jesse Kuhnert
Tapestry/Dojo team member/developer
Open source based consulting work centered around
dojo/tapestry/tacos/hivemind. http://blog.opencomponentry.com
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Re: Newbie help with For and TextField components
Posted by Jim Downing <oj...@cam.ac.uk>.
Hi Firas,
Firas Adiler wrote:
> I'm a bit puzzled myself, but how did you manage to run the app without
> providing setters for 'idx' and 'name' fields:
> public abstract void setIdx(int idx)
> public abstract void setName(String name)?
>
Seems to work fine just defining the getter in other situations - I
think the setter appears by reflection magic.
jim
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RE: Newbie help with For and TextField components
Posted by Firas Adiler <ta...@idigna.com>.
Jim,
I'm a bit puzzled myself, but how did you manage to run the app without
providing setters for 'idx' and 'name' fields:
public abstract void setIdx(int idx)
public abstract void setName(String name)?
Regards,
</Firas>
-----Original Message-----
From: Jim Downing [mailto:ojd20@cam.ac.uk]
Sent: Tuesday, January 09, 2007 3:47 PM
To: users@tapestry.apache.org
Subject: Newbie help with For and TextField components
Hi,
I'm trying to get some simple list editing working using For and TextField
but not having much luck.
Home.html: -
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head>
<title>Example app</title> </head> <body jwcid="@Body"> <h1>Hello
world!</h1> <form jwcid="@Form" success="listener:submit">List of names:
<div jwcid="@For" source="ognl:names" value="ognl:name" index="ognl:idx">
<p><span jwcid="@Insert" value="ognl:idx">1</span> <input
jwcid="@TextField" value="ognl:name" /></p> </div> <input type="submit"
jwcid="@Submit" listener="listener:add" value="Add" /> <input type="submit"
jwcid="@Submit" value="Update" /></form> </body> </html>
Home.java
public abstract class Home extends BasePage implements
PageBeginRenderListener {
private static final Logger LOG = Logger.getLogger(Home.class);
public void pageBeginRender(PageEvent event) {
LOG.info("Begin render. Rewind? " +
getRequestCycle().isRewinding());
if(getNames()== null) {
LOG.info("Initializing names list");
setNames(new ArrayList<String>());
}
}
public void submit() {
LOG.info("Submitted. List is: " + getNames());
}
public void add() {
LOG.info("Adding a blank name to "+ getNames());
List<String> nms = getNames();
nms.add("");
setNames(nms);
}
public abstract List<String> getNames();
public abstract void setNames(List<String> nms);
public abstract String getName();
public abstract int getIdx();
}
When I click the "Add" button I get: -
9627410 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? true
9627411 [btpool0-3] INFO com.example.pages.Home - Initializing names list
9627423 [btpool0-3] INFO com.example.pages.Home - Adding a blank name to
[]
9627424 [btpool0-3] INFO com.example.pages.Home - Submitted. List is:
[ ---- ]
9627424 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? false
Then changing the value in the form input and clicking submit produces
this: -
9638858 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? true
9638858 [btpool0-3] INFO com.example.pages.Home - Initializing names list
9638859 [btpool0-3] INFO com.example.pages.Home - Submitted. List is: []
9638859 [btpool0-3] INFO com.example.pages.Home - Begin render.
Rewind? false
I'm puzzled - why hasn't the list been populated from the TextFields in the
For loop?
Any pointers gratefully received.
cheers,
jim
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