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Posted to users@tapestry.apache.org by Luca Fossato <lu...@gmail.com> on 2008/04/16 19:27:24 UTC

T5 actionlink, ajax zone and user onclick handler

Hi all,

I'm playing with actionlink and zones to understand T5 ajax functions
(Tapestry 5.0.11).
I'd like to define an actionlink like this one:

<t:actionlink t:id="deleteLink" context="myContext"
t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
record ?');">delete</t:actionlink>

where the onclick handler uses a javascript confirmation dialog to ask
to the user if he/she wants to delete the selected record.
It seems to me the Tapestry.linkZone js function "eats" the user
onclick handler and set its own - so it is not possible to execute any
js code prior to invoke the ajax call.

Is it correct or am I missing something ?

I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
function (just an experiment):

--- cut here ---

/** Convert a form or link into a trigger of an Ajax update that
 * updates the indicated Zone.
 */
linkZone : function(element, zoneDiv)
{
  // ... original code until "Otherwise, assume it's just an ordinary
link." comment...

  // Otherwise, assume it's just an ordinary link.
  var onClickValue = element.getAttribute("onclick");
  if (onClickValue != null)
  {
    element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
  }

  var handler = function(event)
  {
      var onBeforeAjaxRes = true;
      var onBeforeAjaxValue = element.getAttribute("tapestry5_onbeforeajax");
      if (onBeforeAjaxValue != null)
      {
        onBeforeAjaxRes = eval(onBeforeAjaxValue);
      }

      // execute the Ajax request only if the original onclick
attribute was not set or if the evaluation
      // of the related function returned true;
      if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
        new Ajax.Request(element.href, { onSuccess : successHandler });

      return false;
  };

  element.onclick = handler;
},  // end of linkZone function

--- cut here ---

that is a 10 minutes "fix", so probably it's not the best solution.
Anyway it seems to work fine for my experiment ;^)
To block the execution of the ajax call, do NOT use a return statement
inside the onclick handler. Example:

<t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
myFunction(myParam);">delete</t:actionlink>

use this instead:

<t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
onclick="myFunction(myParam);">delete</t:actionlink>

because eval() returns the value of the last expression evaluated.
http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval

Does this stuff make sense for you ?? ;^)

Thank you,
Luca Fossato

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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Tobias Wehrum <Le...@dragonlab.de>.
Hi Chris,

while not in this much detail, I also thought that the DOM events may 
cause this problem. Pity even you don't know what to do.

Thanks for your answer,
Tobias

Chris Lewis schrieb:
> Hi Tobias,
>
> Unfortunately I can't think of a clean workaround for that. The issues
> are all in the javascript and how events are dispatched and handled.
> Basically it comes down to 2 problems:
>
> 1) The W3C does not mandate even handler ordering, so if you register a
> handler before another there is no guarantee that it will actually fire
> before the other. Lame.
>
> 2) Stopping the DOM event only stops it's propagation to subsequent DOM
> elements and not subsequent handlers. So that means that even if you
> knew your handler would fire first, stopping the event will not stop the
> zone handler from firing.
>
> Coincidentally my tests show that the mixin's JS handler is fired first,
> but that's no guarantee. If it was then you could override the
> Tapestry.linkZone method to make an explicit check on the event to see
> if has been stopped (event.stopped), and if so cancel the operation. Not
> really a nice option, unfortunately. You could take it further to force
> ordering using some function reference replacement voodoo, but that's a
> tad nasty. Perhaps this logic would be better factored into the
> components. Any other thoughts, anyone?
>
> Tobias Wehrum wrote:
>   
>> Hi Chris,
>>
>> first let me please thank you for the example you've written. It's
>> quite informative.
>>
>> I've discovered a problem with updating a zone - I think it's no
>> problem of your mixin, but you may have an idea how to fix it.
>>
>> The problem is: When I use have an actionlink with the confirm mixin
>> and a t:zone, it doesn't matter whether I click "ok" or "cancel": The
>> function updating the zone will called anyway. Short example:
>>
>> ----------------------------------------------------------------------------------------------------------------------------
>>
>>    <t:zone t:id="testArea">
>>    </t:zone>
>>      <t:actionlink t:id="test" t:zone="testArea"
>> t:mixins="confirm">Test 1</t:actionlink><br/>
>>    <t:actionlink t:id="test2" t:mixins="confirm">Test 2</t:actionlink>
>> ----------------------------------------------------------------------------------------------------------------------------
>>
>>
>> ----------------------------------------------------------------------------------------------------------------------------
>>
>>    @Component
>>    private Zone testArea;
>>      @OnEvent(component="test", value="action")
>>    Zone onActionFromTest()
>>    {
>>        System.out.println("onActionFromTest!");
>>        return testArea;
>>    }
>>
>>    @OnEvent(component="test2", value="action")
>>    void onActionFromTest2()
>>    {
>>        System.out.println("onActionFromTest2!");
>>    }
>> ----------------------------------------------------------------------------------------------------------------------------
>>
>>
>> Now when you click on "Test 1", the console will output
>> "onActionFromTest!", regardless of which choice I make in the confirm
>> dialog.
>> "Test 2" works without problems.
>>
>> Do you - or anybody else - have any idea why this is the case, or even
>> better, a possible solution for it?
>>
>> Thanks in advance,
>> Tobias
>>
>> Chris Lewis schrieb:
>>     
>>> Hi Lucca,
>>>
>>> I'd been looking for a good example to use to write a wiki explaining
>>> the integration javascript by Tapestry, and your request gave me what I
>>> was looking for. Check out the article here:
>>> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
>>> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
>>> from discussing in detail how T5 integrates JS, it shows how to create a
>>> mixin that can be added to link components. The mixin attaches js code
>>> to the component, so that when the link is clicked the user is presented
>>> with a confirmation box. Canceling the box cancels the click, while OK
>>> allows it to proceed as normal. This should be useful for those looking
>>> to add click confirmation functionality, but in your case I'm not sure
>>> if it will help. I ask you to try and see, but the problem will be how
>>> T5 attaches the js handlers for the ajax code (that is, they may fire
>>> before the confirmation code).
>>>
>>> Anyway, I think it will be helpful to those looking for such an
>>> explanation, and I hope it helps you.
>>>
>>> chris
>>>
>>> Luca Fossato wrote:
>>>  
>>>       
>>>> Hi all,
>>>>
>>>> I'm playing with actionlink and zones to understand T5 ajax functions
>>>> (Tapestry 5.0.11).
>>>> I'd like to define an actionlink like this one:
>>>>
>>>> <t:actionlink t:id="deleteLink" context="myContext"
>>>> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
>>>> record ?');">delete</t:actionlink>
>>>>
>>>> where the onclick handler uses a javascript confirmation dialog to ask
>>>> to the user if he/she wants to delete the selected record.
>>>> It seems to me the Tapestry.linkZone js function "eats" the user
>>>> onclick handler and set its own - so it is not possible to execute any
>>>> js code prior to invoke the ajax call.
>>>>
>>>> Is it correct or am I missing something ?
>>>>
>>>> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
>>>> function (just an experiment):
>>>>
>>>> --- cut here ---
>>>>
>>>> /** Convert a form or link into a trigger of an Ajax update that
>>>>  * updates the indicated Zone.
>>>>  */
>>>> linkZone : function(element, zoneDiv)
>>>> {
>>>>   // ... original code until "Otherwise, assume it's just an ordinary
>>>> link." comment...
>>>>
>>>>   // Otherwise, assume it's just an ordinary link.
>>>>   var onClickValue = element.getAttribute("onclick");
>>>>   if (onClickValue != null)
>>>>   {
>>>>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>>>>   }
>>>>
>>>>   var handler = function(event)
>>>>   {
>>>>       var onBeforeAjaxRes = true;
>>>>       var onBeforeAjaxValue =
>>>> element.getAttribute("tapestry5_onbeforeajax");
>>>>       if (onBeforeAjaxValue != null)
>>>>       {
>>>>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>>>>       }
>>>>
>>>>       // execute the Ajax request only if the original onclick
>>>> attribute was not set or if the evaluation
>>>>       // of the related function returned true;
>>>>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>>>>         new Ajax.Request(element.href, { onSuccess : successHandler });
>>>>
>>>>       return false;
>>>>   };
>>>>
>>>>   element.onclick = handler;
>>>> },  // end of linkZone function
>>>>
>>>> --- cut here ---
>>>>
>>>> that is a 10 minutes "fix", so probably it's not the best solution.
>>>> Anyway it seems to work fine for my experiment ;^)
>>>> To block the execution of the ajax call, do NOT use a return statement
>>>> inside the onclick handler. Example:
>>>>
>>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
>>>> myFunction(myParam);">delete</t:actionlink>
>>>>
>>>> use this instead:
>>>>
>>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
>>>> onclick="myFunction(myParam);">delete</t:actionlink>
>>>>
>>>> because eval() returns the value of the last expression evaluated.
>>>> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>>>>
>>>>
>>>> Does this stuff make sense for you ?? ;^)
>>>>
>>>> Thank you,
>>>> Luca Fossato
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>>>> For additional commands, e-mail: users-help@tapestry.apache.org
>>>>
>>>>
>>>>       
>>>>         
>>>   
>>>       
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>>     
>
>   


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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Kalle Korhonen <ka...@gmail.com>.
On Tue, Apr 29, 2008 at 9:14 AM, Chris Lewis <ch...@bellsouth.net> wrote:
> Unfortunately I can't think of a clean workaround for that. The issues
> are all in the javascript and how events are dispatched and handled.
> Basically it comes down to 2 problems:

This is an old thread but found it when I run into a similar issue.

> 1) The W3C does not mandate even handler ordering, so if you register a
> handler before another there is no guarantee that it will actually fire
> before the other. Lame.

I wouldn't say it's lame, it's just the way it is. No other event
system I know of would ever allow ordering event handlers. In fact,
treating all handlers equally allows an option for executing them in
parallel (even if current Javascript engines don't do that).

> 2) Stopping the DOM event only stops it's propagation to subsequent DOM
> elements and not subsequent handlers. So that means that even if you
> knew your handler would fire first, stopping the event will not stop the
> zone handler from firing.
> Coincidentally my tests show that the mixin's JS handler is fired first,
> but that's no guarantee. If it was then you could override the

First of all, thanks for the well-written wiki page Chris, it's very
informative. I'd think the right way to solve the problem is to use
event propagation as intended. That is, in the case of confirm(), you
should target the element inside of your actionlink - for example:

<t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"><span
id="confirmDelete">delete</span></t:actionlink>

Then add a handler for the nested element:
Event.observe($('confirmDelete'), 'click', function(event) {if
(!confirm('are you sure to delete this record ?')) event.stop();});
to stop the event from being propagated to the actionlink handler.

You could probably attach the confirm mixin to an Any component
outputting a span. If you put a button inside, it'd be even easier
since you could just do onclick="return confirm(...);". Unfortunately
it's not possible, or at least not trivial, to create a mixin that you
could attach to the parent element but make it listen to a "click"
event of a nested element - and I don't think it would be cool if the
mixing would programmatically modify the parent element (since that's
how I see you could get it done if you really wanted to).

Kalle

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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Chris Lewis <ch...@bellsouth.net>.
Hi Tobias,

Unfortunately I can't think of a clean workaround for that. The issues
are all in the javascript and how events are dispatched and handled.
Basically it comes down to 2 problems:

1) The W3C does not mandate even handler ordering, so if you register a
handler before another there is no guarantee that it will actually fire
before the other. Lame.

2) Stopping the DOM event only stops it's propagation to subsequent DOM
elements and not subsequent handlers. So that means that even if you
knew your handler would fire first, stopping the event will not stop the
zone handler from firing.

Coincidentally my tests show that the mixin's JS handler is fired first,
but that's no guarantee. If it was then you could override the
Tapestry.linkZone method to make an explicit check on the event to see
if has been stopped (event.stopped), and if so cancel the operation. Not
really a nice option, unfortunately. You could take it further to force
ordering using some function reference replacement voodoo, but that's a
tad nasty. Perhaps this logic would be better factored into the
components. Any other thoughts, anyone?

Tobias Wehrum wrote:
> Hi Chris,
>
> first let me please thank you for the example you've written. It's
> quite informative.
>
> I've discovered a problem with updating a zone - I think it's no
> problem of your mixin, but you may have an idea how to fix it.
>
> The problem is: When I use have an actionlink with the confirm mixin
> and a t:zone, it doesn't matter whether I click "ok" or "cancel": The
> function updating the zone will called anyway. Short example:
>
> ----------------------------------------------------------------------------------------------------------------------------
>
>    <t:zone t:id="testArea">
>    </t:zone>
>      <t:actionlink t:id="test" t:zone="testArea"
> t:mixins="confirm">Test 1</t:actionlink><br/>
>    <t:actionlink t:id="test2" t:mixins="confirm">Test 2</t:actionlink>
> ----------------------------------------------------------------------------------------------------------------------------
>
>
> ----------------------------------------------------------------------------------------------------------------------------
>
>    @Component
>    private Zone testArea;
>      @OnEvent(component="test", value="action")
>    Zone onActionFromTest()
>    {
>        System.out.println("onActionFromTest!");
>        return testArea;
>    }
>
>    @OnEvent(component="test2", value="action")
>    void onActionFromTest2()
>    {
>        System.out.println("onActionFromTest2!");
>    }
> ----------------------------------------------------------------------------------------------------------------------------
>
>
> Now when you click on "Test 1", the console will output
> "onActionFromTest!", regardless of which choice I make in the confirm
> dialog.
> "Test 2" works without problems.
>
> Do you - or anybody else - have any idea why this is the case, or even
> better, a possible solution for it?
>
> Thanks in advance,
> Tobias
>
> Chris Lewis schrieb:
>> Hi Lucca,
>>
>> I'd been looking for a good example to use to write a wiki explaining
>> the integration javascript by Tapestry, and your request gave me what I
>> was looking for. Check out the article here:
>> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
>> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
>> from discussing in detail how T5 integrates JS, it shows how to create a
>> mixin that can be added to link components. The mixin attaches js code
>> to the component, so that when the link is clicked the user is presented
>> with a confirmation box. Canceling the box cancels the click, while OK
>> allows it to proceed as normal. This should be useful for those looking
>> to add click confirmation functionality, but in your case I'm not sure
>> if it will help. I ask you to try and see, but the problem will be how
>> T5 attaches the js handlers for the ajax code (that is, they may fire
>> before the confirmation code).
>>
>> Anyway, I think it will be helpful to those looking for such an
>> explanation, and I hope it helps you.
>>
>> chris
>>
>> Luca Fossato wrote:
>>  
>>> Hi all,
>>>
>>> I'm playing with actionlink and zones to understand T5 ajax functions
>>> (Tapestry 5.0.11).
>>> I'd like to define an actionlink like this one:
>>>
>>> <t:actionlink t:id="deleteLink" context="myContext"
>>> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
>>> record ?');">delete</t:actionlink>
>>>
>>> where the onclick handler uses a javascript confirmation dialog to ask
>>> to the user if he/she wants to delete the selected record.
>>> It seems to me the Tapestry.linkZone js function "eats" the user
>>> onclick handler and set its own - so it is not possible to execute any
>>> js code prior to invoke the ajax call.
>>>
>>> Is it correct or am I missing something ?
>>>
>>> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
>>> function (just an experiment):
>>>
>>> --- cut here ---
>>>
>>> /** Convert a form or link into a trigger of an Ajax update that
>>>  * updates the indicated Zone.
>>>  */
>>> linkZone : function(element, zoneDiv)
>>> {
>>>   // ... original code until "Otherwise, assume it's just an ordinary
>>> link." comment...
>>>
>>>   // Otherwise, assume it's just an ordinary link.
>>>   var onClickValue = element.getAttribute("onclick");
>>>   if (onClickValue != null)
>>>   {
>>>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>>>   }
>>>
>>>   var handler = function(event)
>>>   {
>>>       var onBeforeAjaxRes = true;
>>>       var onBeforeAjaxValue =
>>> element.getAttribute("tapestry5_onbeforeajax");
>>>       if (onBeforeAjaxValue != null)
>>>       {
>>>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>>>       }
>>>
>>>       // execute the Ajax request only if the original onclick
>>> attribute was not set or if the evaluation
>>>       // of the related function returned true;
>>>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>>>         new Ajax.Request(element.href, { onSuccess : successHandler });
>>>
>>>       return false;
>>>   };
>>>
>>>   element.onclick = handler;
>>> },  // end of linkZone function
>>>
>>> --- cut here ---
>>>
>>> that is a 10 minutes "fix", so probably it's not the best solution.
>>> Anyway it seems to work fine for my experiment ;^)
>>> To block the execution of the ajax call, do NOT use a return statement
>>> inside the onclick handler. Example:
>>>
>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
>>> myFunction(myParam);">delete</t:actionlink>
>>>
>>> use this instead:
>>>
>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
>>> onclick="myFunction(myParam);">delete</t:actionlink>
>>>
>>> because eval() returns the value of the last expression evaluated.
>>> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>>>
>>>
>>> Does this stuff make sense for you ?? ;^)
>>>
>>> Thank you,
>>> Luca Fossato
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>>> For additional commands, e-mail: users-help@tapestry.apache.org
>>>
>>>
>>>       
>>
>>   
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>

-- 
http://thegodcode.net


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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Tobias Wehrum <Le...@dragonlab.de>.
Hi Chris,

first let me please thank you for the example you've written. It's quite 
informative.

I've discovered a problem with updating a zone - I think it's no problem 
of your mixin, but you may have an idea how to fix it.

The problem is: When I use have an actionlink with the confirm mixin and 
a t:zone, it doesn't matter whether I click "ok" or "cancel": The 
function updating the zone will called anyway. Short example:

----------------------------------------------------------------------------------------------------------------------------
    <t:zone t:id="testArea">
    </t:zone>
   
    <t:actionlink t:id="test" t:zone="testArea" t:mixins="confirm">Test 
1</t:actionlink><br/>
    <t:actionlink t:id="test2" t:mixins="confirm">Test 2</t:actionlink>
----------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------
    @Component
    private Zone testArea;
   
    @OnEvent(component="test", value="action")
    Zone onActionFromTest()
    {
        System.out.println("onActionFromTest!");
        return testArea;
    }

    @OnEvent(component="test2", value="action")
    void onActionFromTest2()
    {
        System.out.println("onActionFromTest2!");
    }
----------------------------------------------------------------------------------------------------------------------------

Now when you click on "Test 1", the console will output 
"onActionFromTest!", regardless of which choice I make in the confirm 
dialog.
"Test 2" works without problems.

Do you - or anybody else - have any idea why this is the case, or even 
better, a possible solution for it?

Thanks in advance,
Tobias

Chris Lewis schrieb:
> Hi Lucca,
>
> I'd been looking for a good example to use to write a wiki explaining
> the integration javascript by Tapestry, and your request gave me what I
> was looking for. Check out the article here:
> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
> from discussing in detail how T5 integrates JS, it shows how to create a
> mixin that can be added to link components. The mixin attaches js code
> to the component, so that when the link is clicked the user is presented
> with a confirmation box. Canceling the box cancels the click, while OK
> allows it to proceed as normal. This should be useful for those looking
> to add click confirmation functionality, but in your case I'm not sure
> if it will help. I ask you to try and see, but the problem will be how
> T5 attaches the js handlers for the ajax code (that is, they may fire
> before the confirmation code).
>
> Anyway, I think it will be helpful to those looking for such an
> explanation, and I hope it helps you.
>
> chris
>
> Luca Fossato wrote:
>   
>> Hi all,
>>
>> I'm playing with actionlink and zones to understand T5 ajax functions
>> (Tapestry 5.0.11).
>> I'd like to define an actionlink like this one:
>>
>> <t:actionlink t:id="deleteLink" context="myContext"
>> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
>> record ?');">delete</t:actionlink>
>>
>> where the onclick handler uses a javascript confirmation dialog to ask
>> to the user if he/she wants to delete the selected record.
>> It seems to me the Tapestry.linkZone js function "eats" the user
>> onclick handler and set its own - so it is not possible to execute any
>> js code prior to invoke the ajax call.
>>
>> Is it correct or am I missing something ?
>>
>> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
>> function (just an experiment):
>>
>> --- cut here ---
>>
>> /** Convert a form or link into a trigger of an Ajax update that
>>  * updates the indicated Zone.
>>  */
>> linkZone : function(element, zoneDiv)
>> {
>>   // ... original code until "Otherwise, assume it's just an ordinary
>> link." comment...
>>
>>   // Otherwise, assume it's just an ordinary link.
>>   var onClickValue = element.getAttribute("onclick");
>>   if (onClickValue != null)
>>   {
>>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>>   }
>>
>>   var handler = function(event)
>>   {
>>       var onBeforeAjaxRes = true;
>>       var onBeforeAjaxValue = element.getAttribute("tapestry5_onbeforeajax");
>>       if (onBeforeAjaxValue != null)
>>       {
>>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>>       }
>>
>>       // execute the Ajax request only if the original onclick
>> attribute was not set or if the evaluation
>>       // of the related function returned true;
>>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>>         new Ajax.Request(element.href, { onSuccess : successHandler });
>>
>>       return false;
>>   };
>>
>>   element.onclick = handler;
>> },  // end of linkZone function
>>
>> --- cut here ---
>>
>> that is a 10 minutes "fix", so probably it's not the best solution.
>> Anyway it seems to work fine for my experiment ;^)
>> To block the execution of the ajax call, do NOT use a return statement
>> inside the onclick handler. Example:
>>
>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
>> myFunction(myParam);">delete</t:actionlink>
>>
>> use this instead:
>>
>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
>> onclick="myFunction(myParam);">delete</t:actionlink>
>>
>> because eval() returns the value of the last expression evaluated.
>> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>>
>> Does this stuff make sense for you ?? ;^)
>>
>> Thank you,
>> Luca Fossato
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>>   
>>     
>
>   


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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Chris Lewis <ch...@bellsouth.net>.
Andy,

Thanks for that, and I hope you'll find it helpful. I'd been wanting to
write it for a while, but it takes a good chunk of time to write decent
documentation/tutorials. This is why I encourage those out there who
have knowledge of specific aspects of T5 to write articles. There are
some fine ones available now, and they make using Tapestry so much easier.

Chris

Blower, Andy wrote:
> Chris,
>
> Just wanted to say that's a very well written wiki page which seems to pull together all relevant points without being too verbose. Bravo.
>
> Hope you get the urge to write more.
>
> Andy.
>
>   
>> -----Original Message-----
>> From: Luca Fossato [mailto:luca.fossato@gmail.com]
>> Sent: 19 April 2008 22:30
>> To: Tapestry users
>> Subject: Re: T5 actionlink, ajax zone and user onclick handler
>>
>> Hi Chris,
>>
>> thank you !
>>
>> I will read your article and I will try to use the mixin to implement
>> the confirmation dialog for my "delete" actionLink.
>> Give me some days to digest all this stuff and to implement it into my
>> test application ;^)
>>
>> Regards,
>> Luca
>>
>> Chris Lewis wrote:
>>     
>>> Hi Lucca,
>>>
>>> I'd been looking for a good example to use to write a wiki explaining
>>> the integration javascript by Tapestry, and your request gave me what
>>>       
>> I
>>     
>>> was looking for. Check out the article here:
>>> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained
>>>       
>> (project
>>     
>>> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
>>> from discussing in detail how T5 integrates JS, it shows how to
>>>       
>> create a
>>     
>>> mixin that can be added to link components. The mixin attaches js
>>>       
>> code
>>     
>>> to the component, so that when the link is clicked the user is
>>>       
>> presented
>>     
>>> with a confirmation box. Canceling the box cancels the click, while
>>>       
>> OK
>>     
>>> allows it to proceed as normal. This should be useful for those
>>>       
>> looking
>>     
>>> to add click confirmation functionality, but in your case I'm not
>>>       
>> sure
>>     
>>> if it will help. I ask you to try and see, but the problem will be
>>>       
>> how
>>     
>>> T5 attaches the js handlers for the ajax code (that is, they may fire
>>> before the confirmation code).
>>>
>>> Anyway, I think it will be helpful to those looking for such an
>>> explanation, and I hope it helps you.
>>>
>>> chris
>>>       
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>     
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>
>   

-- 
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RE: T5 actionlink, ajax zone and user onclick handler

Posted by "Blower, Andy" <An...@proquest.co.uk>.
Chris,

Just wanted to say that's a very well written wiki page which seems to pull together all relevant points without being too verbose. Bravo.

Hope you get the urge to write more.

Andy.

> -----Original Message-----
> From: Luca Fossato [mailto:luca.fossato@gmail.com]
> Sent: 19 April 2008 22:30
> To: Tapestry users
> Subject: Re: T5 actionlink, ajax zone and user onclick handler
>
> Hi Chris,
>
> thank you !
>
> I will read your article and I will try to use the mixin to implement
> the confirmation dialog for my "delete" actionLink.
> Give me some days to digest all this stuff and to implement it into my
> test application ;^)
>
> Regards,
> Luca
>
> Chris Lewis wrote:
> > Hi Lucca,
> >
> > I'd been looking for a good example to use to write a wiki explaining
> > the integration javascript by Tapestry, and your request gave me what
> I
> > was looking for. Check out the article here:
> > http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained
> (project
> > source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
> > from discussing in detail how T5 integrates JS, it shows how to
> create a
> > mixin that can be added to link components. The mixin attaches js
> code
> > to the component, so that when the link is clicked the user is
> presented
> > with a confirmation box. Canceling the box cancels the click, while
> OK
> > allows it to proceed as normal. This should be useful for those
> looking
> > to add click confirmation functionality, but in your case I'm not
> sure
> > if it will help. I ask you to try and see, but the problem will be
> how
> > T5 attaches the js handlers for the ajax code (that is, they may fire
> > before the confirmation code).
> >
> > Anyway, I think it will be helpful to those looking for such an
> > explanation, and I hope it helps you.
> >
> > chris
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org


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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Luca Fossato <lu...@gmail.com>.
Hi Chris,

thank you !

I will read your article and I will try to use the mixin to implement 
the confirmation dialog for my "delete" actionLink.
Give me some days to digest all this stuff and to implement it into my 
test application ;^)

Regards,
Luca

Chris Lewis wrote:
> Hi Lucca,
> 
> I'd been looking for a good example to use to write a wiki explaining
> the integration javascript by Tapestry, and your request gave me what I
> was looking for. Check out the article here:
> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
> from discussing in detail how T5 integrates JS, it shows how to create a
> mixin that can be added to link components. The mixin attaches js code
> to the component, so that when the link is clicked the user is presented
> with a confirmation box. Canceling the box cancels the click, while OK
> allows it to proceed as normal. This should be useful for those looking
> to add click confirmation functionality, but in your case I'm not sure
> if it will help. I ask you to try and see, but the problem will be how
> T5 attaches the js handlers for the ajax code (that is, they may fire
> before the confirmation code).
> 
> Anyway, I think it will be helpful to those looking for such an
> explanation, and I hope it helps you.
> 
> chris

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Re: T5 actionlink, ajax zone and user onclick handler

Posted by "Filip S. Adamsen" <fs...@fsadev.com>.
Umm, that's exactly what Tapestry does...

-Filip

zack1403 skrev:
> Why doesnt tapestry attach events to the DOM instead of using onClick?
> 
> Zack
> 
> 
> Chris Lewis-5 wrote:
>> Hi Lucca,
>>
>> I'd been looking for a good example to use to write a wiki explaining
>> the integration javascript by Tapestry, and your request gave me what I
>> was looking for. Check out the article here:
>> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
>> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
>> from discussing in detail how T5 integrates JS, it shows how to create a
>> mixin that can be added to link components. The mixin attaches js code
>> to the component, so that when the link is clicked the user is presented
>> with a confirmation box. Canceling the box cancels the click, while OK
>> allows it to proceed as normal. This should be useful for those looking
>> to add click confirmation functionality, but in your case I'm not sure
>> if it will help. I ask you to try and see, but the problem will be how
>> T5 attaches the js handlers for the ajax code (that is, they may fire
>> before the confirmation code).
>>
>> Anyway, I think it will be helpful to those looking for such an
>> explanation, and I hope it helps you.
>>
>> chris
>>
>> Luca Fossato wrote:
>>> Hi all,
>>>
>>> I'm playing with actionlink and zones to understand T5 ajax functions
>>> (Tapestry 5.0.11).
>>> I'd like to define an actionlink like this one:
>>>
>>> <t:actionlink t:id="deleteLink" context="myContext"
>>> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
>>> record ?');">delete</t:actionlink>
>>>
>>> where the onclick handler uses a javascript confirmation dialog to ask
>>> to the user if he/she wants to delete the selected record.
>>> It seems to me the Tapestry.linkZone js function "eats" the user
>>> onclick handler and set its own - so it is not possible to execute any
>>> js code prior to invoke the ajax call.
>>>
>>> Is it correct or am I missing something ?
>>>
>>> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
>>> function (just an experiment):
>>>
>>> --- cut here ---
>>>
>>> /** Convert a form or link into a trigger of an Ajax update that
>>>  * updates the indicated Zone.
>>>  */
>>> linkZone : function(element, zoneDiv)
>>> {
>>>   // ... original code until "Otherwise, assume it's just an ordinary
>>> link." comment...
>>>
>>>   // Otherwise, assume it's just an ordinary link.
>>>   var onClickValue = element.getAttribute("onclick");
>>>   if (onClickValue != null)
>>>   {
>>>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>>>   }
>>>
>>>   var handler = function(event)
>>>   {
>>>       var onBeforeAjaxRes = true;
>>>       var onBeforeAjaxValue =
>>> element.getAttribute("tapestry5_onbeforeajax");
>>>       if (onBeforeAjaxValue != null)
>>>       {
>>>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>>>       }
>>>
>>>       // execute the Ajax request only if the original onclick
>>> attribute was not set or if the evaluation
>>>       // of the related function returned true;
>>>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>>>         new Ajax.Request(element.href, { onSuccess : successHandler });
>>>
>>>       return false;
>>>   };
>>>
>>>   element.onclick = handler;
>>> },  // end of linkZone function
>>>
>>> --- cut here ---
>>>
>>> that is a 10 minutes "fix", so probably it's not the best solution.
>>> Anyway it seems to work fine for my experiment ;^)
>>> To block the execution of the ajax call, do NOT use a return statement
>>> inside the onclick handler. Example:
>>>
>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
>>> myFunction(myParam);">delete</t:actionlink>
>>>
>>> use this instead:
>>>
>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
>>> onclick="myFunction(myParam);">delete</t:actionlink>
>>>
>>> because eval() returns the value of the last expression evaluated.
>>> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>>>
>>> Does this stuff make sense for you ?? ;^)
>>>
>>> Thank you,
>>> Luca Fossato
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>>> For additional commands, e-mail: users-help@tapestry.apache.org
>>>
>>>
>>>   
>> -- 
>> http://thegodcode.net
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>>
> 

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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Chris Lewis <ch...@bellsouth.net>.
I don't understand - it uses the modern DOM events system, abstracted
(partially) by tapestry.js, and further abstracted by the underlying
prototype.js library. What is it you are asking?

zack1403 wrote:
> Why doesnt tapestry attach events to the DOM instead of using onClick?
>
> Zack
>
>
> Chris Lewis-5 wrote:
>   
>> Hi Lucca,
>>
>> I'd been looking for a good example to use to write a wiki explaining
>> the integration javascript by Tapestry, and your request gave me what I
>> was looking for. Check out the article here:
>> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
>> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
>> from discussing in detail how T5 integrates JS, it shows how to create a
>> mixin that can be added to link components. The mixin attaches js code
>> to the component, so that when the link is clicked the user is presented
>> with a confirmation box. Canceling the box cancels the click, while OK
>> allows it to proceed as normal. This should be useful for those looking
>> to add click confirmation functionality, but in your case I'm not sure
>> if it will help. I ask you to try and see, but the problem will be how
>> T5 attaches the js handlers for the ajax code (that is, they may fire
>> before the confirmation code).
>>
>> Anyway, I think it will be helpful to those looking for such an
>> explanation, and I hope it helps you.
>>
>> chris
>>
>> Luca Fossato wrote:
>>     
>>> Hi all,
>>>
>>> I'm playing with actionlink and zones to understand T5 ajax functions
>>> (Tapestry 5.0.11).
>>> I'd like to define an actionlink like this one:
>>>
>>> <t:actionlink t:id="deleteLink" context="myContext"
>>> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
>>> record ?');">delete</t:actionlink>
>>>
>>> where the onclick handler uses a javascript confirmation dialog to ask
>>> to the user if he/she wants to delete the selected record.
>>> It seems to me the Tapestry.linkZone js function "eats" the user
>>> onclick handler and set its own - so it is not possible to execute any
>>> js code prior to invoke the ajax call.
>>>
>>> Is it correct or am I missing something ?
>>>
>>> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
>>> function (just an experiment):
>>>
>>> --- cut here ---
>>>
>>> /** Convert a form or link into a trigger of an Ajax update that
>>>  * updates the indicated Zone.
>>>  */
>>> linkZone : function(element, zoneDiv)
>>> {
>>>   // ... original code until "Otherwise, assume it's just an ordinary
>>> link." comment...
>>>
>>>   // Otherwise, assume it's just an ordinary link.
>>>   var onClickValue = element.getAttribute("onclick");
>>>   if (onClickValue != null)
>>>   {
>>>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>>>   }
>>>
>>>   var handler = function(event)
>>>   {
>>>       var onBeforeAjaxRes = true;
>>>       var onBeforeAjaxValue =
>>> element.getAttribute("tapestry5_onbeforeajax");
>>>       if (onBeforeAjaxValue != null)
>>>       {
>>>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>>>       }
>>>
>>>       // execute the Ajax request only if the original onclick
>>> attribute was not set or if the evaluation
>>>       // of the related function returned true;
>>>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>>>         new Ajax.Request(element.href, { onSuccess : successHandler });
>>>
>>>       return false;
>>>   };
>>>
>>>   element.onclick = handler;
>>> },  // end of linkZone function
>>>
>>> --- cut here ---
>>>
>>> that is a 10 minutes "fix", so probably it's not the best solution.
>>> Anyway it seems to work fine for my experiment ;^)
>>> To block the execution of the ajax call, do NOT use a return statement
>>> inside the onclick handler. Example:
>>>
>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
>>> myFunction(myParam);">delete</t:actionlink>
>>>
>>> use this instead:
>>>
>>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
>>> onclick="myFunction(myParam);">delete</t:actionlink>
>>>
>>> because eval() returns the value of the last expression evaluated.
>>> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>>>
>>> Does this stuff make sense for you ?? ;^)
>>>
>>> Thank you,
>>> Luca Fossato
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>>> For additional commands, e-mail: users-help@tapestry.apache.org
>>>
>>>
>>>   
>>>       
>> -- 
>> http://thegodcode.net
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>>
>>     
>
>   

-- 
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Re: T5 actionlink, ajax zone and user onclick handler

Posted by zack1403 <za...@gmail.com>.
Why doesnt tapestry attach events to the DOM instead of using onClick?

Zack


Chris Lewis-5 wrote:
> 
> Hi Lucca,
> 
> I'd been looking for a good example to use to write a wiki explaining
> the integration javascript by Tapestry, and your request gave me what I
> was looking for. Check out the article here:
> http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
> source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
> from discussing in detail how T5 integrates JS, it shows how to create a
> mixin that can be added to link components. The mixin attaches js code
> to the component, so that when the link is clicked the user is presented
> with a confirmation box. Canceling the box cancels the click, while OK
> allows it to proceed as normal. This should be useful for those looking
> to add click confirmation functionality, but in your case I'm not sure
> if it will help. I ask you to try and see, but the problem will be how
> T5 attaches the js handlers for the ajax code (that is, they may fire
> before the confirmation code).
> 
> Anyway, I think it will be helpful to those looking for such an
> explanation, and I hope it helps you.
> 
> chris
> 
> Luca Fossato wrote:
>> Hi all,
>>
>> I'm playing with actionlink and zones to understand T5 ajax functions
>> (Tapestry 5.0.11).
>> I'd like to define an actionlink like this one:
>>
>> <t:actionlink t:id="deleteLink" context="myContext"
>> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
>> record ?');">delete</t:actionlink>
>>
>> where the onclick handler uses a javascript confirmation dialog to ask
>> to the user if he/she wants to delete the selected record.
>> It seems to me the Tapestry.linkZone js function "eats" the user
>> onclick handler and set its own - so it is not possible to execute any
>> js code prior to invoke the ajax call.
>>
>> Is it correct or am I missing something ?
>>
>> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
>> function (just an experiment):
>>
>> --- cut here ---
>>
>> /** Convert a form or link into a trigger of an Ajax update that
>>  * updates the indicated Zone.
>>  */
>> linkZone : function(element, zoneDiv)
>> {
>>   // ... original code until "Otherwise, assume it's just an ordinary
>> link." comment...
>>
>>   // Otherwise, assume it's just an ordinary link.
>>   var onClickValue = element.getAttribute("onclick");
>>   if (onClickValue != null)
>>   {
>>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>>   }
>>
>>   var handler = function(event)
>>   {
>>       var onBeforeAjaxRes = true;
>>       var onBeforeAjaxValue =
>> element.getAttribute("tapestry5_onbeforeajax");
>>       if (onBeforeAjaxValue != null)
>>       {
>>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>>       }
>>
>>       // execute the Ajax request only if the original onclick
>> attribute was not set or if the evaluation
>>       // of the related function returned true;
>>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>>         new Ajax.Request(element.href, { onSuccess : successHandler });
>>
>>       return false;
>>   };
>>
>>   element.onclick = handler;
>> },  // end of linkZone function
>>
>> --- cut here ---
>>
>> that is a 10 minutes "fix", so probably it's not the best solution.
>> Anyway it seems to work fine for my experiment ;^)
>> To block the execution of the ajax call, do NOT use a return statement
>> inside the onclick handler. Example:
>>
>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
>> myFunction(myParam);">delete</t:actionlink>
>>
>> use this instead:
>>
>> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
>> onclick="myFunction(myParam);">delete</t:actionlink>
>>
>> because eval() returns the value of the last expression evaluated.
>> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>>
>> Does this stuff make sense for you ?? ;^)
>>
>> Thank you,
>> Luca Fossato
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>>   
> 
> -- 
> http://thegodcode.net
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
> 
> 
> 

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Re: T5 actionlink, ajax zone and user onclick handler

Posted by Chris Lewis <ch...@bellsouth.net>.
Hi Lucca,

I'd been looking for a good example to use to write a wiki explaining
the integration javascript by Tapestry, and your request gave me what I
was looking for. Check out the article here:
http://wiki.apache.org/tapestry/Tapestry5AndJavaScriptExplained (project
source: http://thegodcode.net/tapestry5/jsclarity-project.zip). Apart
from discussing in detail how T5 integrates JS, it shows how to create a
mixin that can be added to link components. The mixin attaches js code
to the component, so that when the link is clicked the user is presented
with a confirmation box. Canceling the box cancels the click, while OK
allows it to proceed as normal. This should be useful for those looking
to add click confirmation functionality, but in your case I'm not sure
if it will help. I ask you to try and see, but the problem will be how
T5 attaches the js handlers for the ajax code (that is, they may fire
before the confirmation code).

Anyway, I think it will be helpful to those looking for such an
explanation, and I hope it helps you.

chris

Luca Fossato wrote:
> Hi all,
>
> I'm playing with actionlink and zones to understand T5 ajax functions
> (Tapestry 5.0.11).
> I'd like to define an actionlink like this one:
>
> <t:actionlink t:id="deleteLink" context="myContext"
> t:zone="zoneToUpdate" onclick="confirm('are you sure to delete this
> record ?');">delete</t:actionlink>
>
> where the onclick handler uses a javascript confirmation dialog to ask
> to the user if he/she wants to delete the selected record.
> It seems to me the Tapestry.linkZone js function "eats" the user
> onclick handler and set its own - so it is not possible to execute any
> js code prior to invoke the ajax call.
>
> Is it correct or am I missing something ?
>
> I tried to "fix" this behaviour, modifying a bit the Tapestry.linkZone
> function (just an experiment):
>
> --- cut here ---
>
> /** Convert a form or link into a trigger of an Ajax update that
>  * updates the indicated Zone.
>  */
> linkZone : function(element, zoneDiv)
> {
>   // ... original code until "Otherwise, assume it's just an ordinary
> link." comment...
>
>   // Otherwise, assume it's just an ordinary link.
>   var onClickValue = element.getAttribute("onclick");
>   if (onClickValue != null)
>   {
>     element.setAttribute("tapestry5_onbeforeajax",  onClickValue);
>   }
>
>   var handler = function(event)
>   {
>       var onBeforeAjaxRes = true;
>       var onBeforeAjaxValue = element.getAttribute("tapestry5_onbeforeajax");
>       if (onBeforeAjaxValue != null)
>       {
>         onBeforeAjaxRes = eval(onBeforeAjaxValue);
>       }
>
>       // execute the Ajax request only if the original onclick
> attribute was not set or if the evaluation
>       // of the related function returned true;
>       if (onBeforeAjaxRes === undefined || onBeforeAjaxRes)
>         new Ajax.Request(element.href, { onSuccess : successHandler });
>
>       return false;
>   };
>
>   element.onclick = handler;
> },  // end of linkZone function
>
> --- cut here ---
>
> that is a 10 minutes "fix", so probably it's not the best solution.
> Anyway it seems to work fine for my experiment ;^)
> To block the execution of the ajax call, do NOT use a return statement
> inside the onclick handler. Example:
>
> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate" onclick="return
> myFunction(myParam);">delete</t:actionlink>
>
> use this instead:
>
> <t:actionlink t:id="deleteLink" t:zone="zoneToUpdate"
> onclick="myFunction(myParam);">delete</t:actionlink>
>
> because eval() returns the value of the last expression evaluated.
> http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Functions:eval
>
> Does this stuff make sense for you ?? ;^)
>
> Thank you,
> Luca Fossato
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>
>   

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