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Posted to users@tapestry.apache.org by Michael Courcy <mi...@gmail.com> on 2008/01/07 08:46:37 UTC
What's heartbeat ?
Hi list,
As I start to read the code on components I often see heartbeat
@Environmental
private Heartbeat heartbeat;
with heartbeat.begin and heartbeat.end
Can someone explain the role of this object and its methods invocations
(begin and end) beacause it's not really clear in my mind.
Thanks a lot.
--
Michael Courcy
http://courcy.blogspot.com
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Re: What's heartbeat ?
Posted by Chris Lewis <ch...@bellsouth.net>.
One reason
Michael Courcy wrote:
> Gabriel Landais a écrit :
>> Michael Courcy a écrit :
>>> If you look at this exemple : TreeGridComponent
>>> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>>
>>> a hearbeat.begin is called in beginRender and heartbeat.end is
>>> called in afterRender but you can never read a call to defer, so can
>>> you explain why the author of this component call begin and end ? I
>>> really can't explain myself.
>> I've based my component on
>> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
>> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
>> really understanding how it heartbeat works... As I don't use defer,
>> I don't even know if it is useful...
>> Gabriel
> But do you see a different hehaviour if you remove this two lines ?
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>
>
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Re: What's heartbeat ?
Posted by Howard Lewis Ship <hl...@gmail.com>.
The Field/Label example is pretty canonical, you don't know the order
they will render in (the Label generally before the Field, in western
languages). The Label knows the field but not vice-versa. You need
the Field to render before you can fully render the Label. Thus we
put off a portion of the render, making use of T5's DOM, to fill in
the detail (the for attribute of the rendered <label> element) until
we know both have rendered.
On Jan 7, 2008 8:23 AM, Chris Lewis <ch...@bellsouth.net> wrote:
> I think we're clear now on the use of defer for for this task. The
> common question now seems to be about who does/is supposed to call
> start() and end(). In my example (as well as yours in less detail) I
> don't talk about who starts/ends and why. I simply cover why defer is
> needed. I think any inputs on these questions would be generally helpful:
>
> 1) Can you use only Heartbeat#defer without start()ing or end()ing?
Yes
>
> 2) If so, who start()s and end()s it?
An enclosing component, such as a Loop. Also, the page initialization
logic starts a Heartbeat for the entire page. Heartbeats are allowed
to nest.
>
> 3) If not, who must start() and end() it?
Just whoever starts it must also end it. If you end up writing a kind
of looping component, you should add a Heartbeat to it. I wonder if
that could be encapsulated inside a Mixin?
>
>
> Kristian Marinkovic wrote:
> > sorry for jumping in but consider a label-input scenario/exampel ....
> >
> > if you want to generate the "for" attribute for your label you dont know
> > the
> > id of the input field when the label is rendered before the field.
> > therefore the
> > label components defers its rendering using the heartbeat service.
> >
> > g,
> > kirs
> >
> >
> >
> >
> > Michael Courcy <mi...@gmail.com>
> > 07.01.2008 16:17
> > Bitte antworten an
> > "Tapestry users" <us...@tapestry.apache.org>
> >
> >
> > An
> > Tapestry users <us...@tapestry.apache.org>
> > Kopie
> >
> > Thema
> > Re: What's heartbeat ?
> >
> >
> >
> >
> >
> >
> >
> > Hi Chris,
> >
> > Chris Lewis a écrit :
> >
> >> I'm not an expert on this, but I can offer you a real need for
> >> defer(). Suppose you have a mixin that attaches some trivial piece of
> >> JavaScript to components that use it; for example, a key logger. As
> >> far as the JS, what you need to do is register a few DOM event
> >> handlers on an element - probably onkeypress or onkeyup, etc. Let's
> >> suppose you wrote a class that creates such objects, and all you need
> >> to instantiate them is the DOM id of the element.
> >>
> >> In a simple case all you'd need to do is have your mixin include the
> >> javascript and provide a line (like support.addScript()) to
> >> instantiate the object in JS code - providing the component id, which
> >> I think you can get through something like ComponentResources. Now, if
> >> in your template code you have one component for which you explicitly
> >> provide the DOM id, then your mixin will end up with this id. However
> >> there are situations where you simply can't know the id before hand,
> >> and in such cases you must rely on Tapestry to provide it.
> >>
> >> A classic example is looping. If you have a loop that for some reason
> >> creates a variable number of components, to which you'd like to attach
> >> instances of your JS key logger, then you need to get the ids (created
> >> on the fly) from Tapestry. What's more, you can't assk a component for
> >> its id until it has already been assigned one, and the only way to be
> >> sure that your code executes after the assignment happen is to use
> >> Heartbeat#defer.
> >>
> >> Now as far as when a heartbeat is created, and when/who must call
> >> start() and end(), I'm not entirely sure. I think that a component
> >> whose behavior interacts with/depends on that of other
> >> components/mixins must use heartbeats to coordinate.
> >>
> > I understand this concept my question is how can they cooperate, It
> > would be really nice to have a live example involving the use of
> > heartbeat to get Ids of "only known at runtime component".
> >
> > The only example I could find about heartbeat is to defer the firing of
> > an event :
> > Taken from http://wiki.apache.org/tapestry/Tapestry5SubmitContextComponent
> >
> > Runnable sendNotification = new Runnable()
> > {
> > public void run()
> > {
> > _resources.triggerEvent(SELECTED_EVENT, new Object[]
> > {context}, null);
> > }
> > };
> >
> > // When not deferred, don't wait, fire the event now (actually,
> > at the end of the current
> > // heartbeat). This is most likely because the Submit is inside a
> > Loop and some contextual
> > // information will change if we defer. Another option might be
> > to wait until the next
> > // heartbeak?
> >
> > if (_defer)
> > _formSupport.defer(sendNotification);
> > else
> > _heartbeat.defer(sendNotification);
> >
> >
> > But If you read the rest of this exemple, _heartbeat.begin,
> > _heartbeat.end are never called ... Who call them ? What means calling
> > them ?
> >
> >> I hope this helps. I'd suggest looking into the source for heartbeat's
> >> implementation as well as what really happens inside form support's
> >> defer method. You're not alone in your questions and expanded docs on
> >> this would be helpful.
> >>
> > You're right I think a little dive in the source code would be
> > refreshing :-)
> >
> >> sincerely,
> >> chris
> >>
> >> PS - irc.freenode.net #tapestry
> >>
> >> Michael Courcy wrote:
> >>
> >>> Gabriel Landais a écrit :
> >>>
> >>>> Michael Courcy a écrit :
> >>>>
> >>>>> If you look at this exemple : TreeGridComponent
> >>>>>
> >>>>>
> > http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
> >
> >
> >>>>> a hearbeat.begin is called in beginRender and heartbeat.end is
> >>>>> called in afterRender but you can never read a call to defer, so
> >>>>> can you explain why the author of this component call begin and end
> >>>>> ? I really can't explain myself.
> >>>>>
> >>>> I've based my component on
> >>>> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents
> >>>>
> >>>> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
> >>>> really understanding how it heartbeat works... As I don't use defer,
> >>>> I don't even know if it is useful...
> >>>> Gabriel
> >>>>
> >>> But do you see a different hehaviour if you remove this two lines ?
> >>>
> >>>> ---------------------------------------------------------------------
> >>>> 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
> >>
> >>
> >>
> >
> >
> >
>
>
--
Howard M. Lewis Ship
Creator Apache Tapestry and Apache HiveMind
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Re: What's heartbeat ?
Posted by Chris Lewis <ch...@bellsouth.net>.
I think we're clear now on the use of defer for for this task. The
common question now seems to be about who does/is supposed to call
start() and end(). In my example (as well as yours in less detail) I
don't talk about who starts/ends and why. I simply cover why defer is
needed. I think any inputs on these questions would be generally helpful:
1) Can you use only Heartbeat#defer without start()ing or end()ing?
2) If so, who start()s and end()s it?
3) If not, who must start() and end() it?
Kristian Marinkovic wrote:
> sorry for jumping in but consider a label-input scenario/exampel ....
>
> if you want to generate the "for" attribute for your label you dont know
> the
> id of the input field when the label is rendered before the field.
> therefore the
> label components defers its rendering using the heartbeat service.
>
> g,
> kirs
>
>
>
>
> Michael Courcy <mi...@gmail.com>
> 07.01.2008 16:17
> Bitte antworten an
> "Tapestry users" <us...@tapestry.apache.org>
>
>
> An
> Tapestry users <us...@tapestry.apache.org>
> Kopie
>
> Thema
> Re: What's heartbeat ?
>
>
>
>
>
>
>
> Hi Chris,
>
> Chris Lewis a écrit :
>
>> I'm not an expert on this, but I can offer you a real need for
>> defer(). Suppose you have a mixin that attaches some trivial piece of
>> JavaScript to components that use it; for example, a key logger. As
>> far as the JS, what you need to do is register a few DOM event
>> handlers on an element - probably onkeypress or onkeyup, etc. Let's
>> suppose you wrote a class that creates such objects, and all you need
>> to instantiate them is the DOM id of the element.
>>
>> In a simple case all you'd need to do is have your mixin include the
>> javascript and provide a line (like support.addScript()) to
>> instantiate the object in JS code - providing the component id, which
>> I think you can get through something like ComponentResources. Now, if
>> in your template code you have one component for which you explicitly
>> provide the DOM id, then your mixin will end up with this id. However
>> there are situations where you simply can't know the id before hand,
>> and in such cases you must rely on Tapestry to provide it.
>>
>> A classic example is looping. If you have a loop that for some reason
>> creates a variable number of components, to which you'd like to attach
>> instances of your JS key logger, then you need to get the ids (created
>> on the fly) from Tapestry. What's more, you can't assk a component for
>> its id until it has already been assigned one, and the only way to be
>> sure that your code executes after the assignment happen is to use
>> Heartbeat#defer.
>>
>> Now as far as when a heartbeat is created, and when/who must call
>> start() and end(), I'm not entirely sure. I think that a component
>> whose behavior interacts with/depends on that of other
>> components/mixins must use heartbeats to coordinate.
>>
> I understand this concept my question is how can they cooperate, It
> would be really nice to have a live example involving the use of
> heartbeat to get Ids of "only known at runtime component".
>
> The only example I could find about heartbeat is to defer the firing of
> an event :
> Taken from http://wiki.apache.org/tapestry/Tapestry5SubmitContextComponent
>
> Runnable sendNotification = new Runnable()
> {
> public void run()
> {
> _resources.triggerEvent(SELECTED_EVENT, new Object[]
> {context}, null);
> }
> };
>
> // When not deferred, don't wait, fire the event now (actually,
> at the end of the current
> // heartbeat). This is most likely because the Submit is inside a
> Loop and some contextual
> // information will change if we defer. Another option might be
> to wait until the next
> // heartbeak?
>
> if (_defer)
> _formSupport.defer(sendNotification);
> else
> _heartbeat.defer(sendNotification);
>
>
> But If you read the rest of this exemple, _heartbeat.begin,
> _heartbeat.end are never called ... Who call them ? What means calling
> them ?
>
>> I hope this helps. I'd suggest looking into the source for heartbeat's
>> implementation as well as what really happens inside form support's
>> defer method. You're not alone in your questions and expanded docs on
>> this would be helpful.
>>
> You're right I think a little dive in the source code would be
> refreshing :-)
>
>> sincerely,
>> chris
>>
>> PS - irc.freenode.net #tapestry
>>
>> Michael Courcy wrote:
>>
>>> Gabriel Landais a écrit :
>>>
>>>> Michael Courcy a écrit :
>>>>
>>>>> If you look at this exemple : TreeGridComponent
>>>>>
>>>>>
> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>
>
>>>>> a hearbeat.begin is called in beginRender and heartbeat.end is
>>>>> called in afterRender but you can never read a call to defer, so
>>>>> can you explain why the author of this component call begin and end
>>>>> ? I really can't explain myself.
>>>>>
>>>> I've based my component on
>>>> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents
>>>>
>>>> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
>>>> really understanding how it heartbeat works... As I don't use defer,
>>>> I don't even know if it is useful...
>>>> Gabriel
>>>>
>>> But do you see a different hehaviour if you remove this two lines ?
>>>
>>>> ---------------------------------------------------------------------
>>>> 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
>>
>>
>>
>
>
>
Re: What's heartbeat ?
Posted by Kristian Marinkovic <kr...@porsche.co.at>.
sorry for jumping in but consider a label-input scenario/exampel ....
if you want to generate the "for" attribute for your label you dont know
the
id of the input field when the label is rendered before the field.
therefore the
label components defers its rendering using the heartbeat service.
g,
kirs
Michael Courcy <mi...@gmail.com>
07.01.2008 16:17
Bitte antworten an
"Tapestry users" <us...@tapestry.apache.org>
An
Tapestry users <us...@tapestry.apache.org>
Kopie
Thema
Re: What's heartbeat ?
Hi Chris,
Chris Lewis a écrit :
> I'm not an expert on this, but I can offer you a real need for
> defer(). Suppose you have a mixin that attaches some trivial piece of
> JavaScript to components that use it; for example, a key logger. As
> far as the JS, what you need to do is register a few DOM event
> handlers on an element - probably onkeypress or onkeyup, etc. Let's
> suppose you wrote a class that creates such objects, and all you need
> to instantiate them is the DOM id of the element.
>
> In a simple case all you'd need to do is have your mixin include the
> javascript and provide a line (like support.addScript()) to
> instantiate the object in JS code - providing the component id, which
> I think you can get through something like ComponentResources. Now, if
> in your template code you have one component for which you explicitly
> provide the DOM id, then your mixin will end up with this id. However
> there are situations where you simply can't know the id before hand,
> and in such cases you must rely on Tapestry to provide it.
>
> A classic example is looping. If you have a loop that for some reason
> creates a variable number of components, to which you'd like to attach
> instances of your JS key logger, then you need to get the ids (created
> on the fly) from Tapestry. What's more, you can't assk a component for
> its id until it has already been assigned one, and the only way to be
> sure that your code executes after the assignment happen is to use
> Heartbeat#defer.
>
> Now as far as when a heartbeat is created, and when/who must call
> start() and end(), I'm not entirely sure. I think that a component
> whose behavior interacts with/depends on that of other
> components/mixins must use heartbeats to coordinate.
I understand this concept my question is how can they cooperate, It
would be really nice to have a live example involving the use of
heartbeat to get Ids of "only known at runtime component".
The only example I could find about heartbeat is to defer the firing of
an event :
Taken from http://wiki.apache.org/tapestry/Tapestry5SubmitContextComponent
Runnable sendNotification = new Runnable()
{
public void run()
{
_resources.triggerEvent(SELECTED_EVENT, new Object[]
{context}, null);
}
};
// When not deferred, don't wait, fire the event now (actually,
at the end of the current
// heartbeat). This is most likely because the Submit is inside a
Loop and some contextual
// information will change if we defer. Another option might be
to wait until the next
// heartbeak?
if (_defer)
_formSupport.defer(sendNotification);
else
_heartbeat.defer(sendNotification);
But If you read the rest of this exemple, _heartbeat.begin,
_heartbeat.end are never called ... Who call them ? What means calling
them ?
>
> I hope this helps. I'd suggest looking into the source for heartbeat's
> implementation as well as what really happens inside form support's
> defer method. You're not alone in your questions and expanded docs on
> this would be helpful.
You're right I think a little dive in the source code would be
refreshing :-)
>
> sincerely,
> chris
>
> PS - irc.freenode.net #tapestry
>
> Michael Courcy wrote:
>> Gabriel Landais a écrit :
>>> Michael Courcy a écrit :
>>>> If you look at this exemple : TreeGridComponent
>>>>
http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>>>
>>>> a hearbeat.begin is called in beginRender and heartbeat.end is
>>>> called in afterRender but you can never read a call to defer, so
>>>> can you explain why the author of this component call begin and end
>>>> ? I really can't explain myself.
>>> I've based my component on
>>> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents
>
>>> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
>>> really understanding how it heartbeat works... As I don't use defer,
>>> I don't even know if it is useful...
>>> Gabriel
>> But do you see a different hehaviour if you remove this two lines ?
>>>
>>> ---------------------------------------------------------------------
>>> 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
>
>
--
Michael Courcy
http://courcy.blogspot.com
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
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Re: What's heartbeat ?
Posted by Michael Courcy <mi...@gmail.com>.
Hi Chris,
Chris Lewis a écrit :
> I'm not an expert on this, but I can offer you a real need for
> defer(). Suppose you have a mixin that attaches some trivial piece of
> JavaScript to components that use it; for example, a key logger. As
> far as the JS, what you need to do is register a few DOM event
> handlers on an element - probably onkeypress or onkeyup, etc. Let's
> suppose you wrote a class that creates such objects, and all you need
> to instantiate them is the DOM id of the element.
>
> In a simple case all you'd need to do is have your mixin include the
> javascript and provide a line (like support.addScript()) to
> instantiate the object in JS code - providing the component id, which
> I think you can get through something like ComponentResources. Now, if
> in your template code you have one component for which you explicitly
> provide the DOM id, then your mixin will end up with this id. However
> there are situations where you simply can't know the id before hand,
> and in such cases you must rely on Tapestry to provide it.
>
> A classic example is looping. If you have a loop that for some reason
> creates a variable number of components, to which you'd like to attach
> instances of your JS key logger, then you need to get the ids (created
> on the fly) from Tapestry. What's more, you can't assk a component for
> its id until it has already been assigned one, and the only way to be
> sure that your code executes after the assignment happen is to use
> Heartbeat#defer.
>
> Now as far as when a heartbeat is created, and when/who must call
> start() and end(), I'm not entirely sure. I think that a component
> whose behavior interacts with/depends on that of other
> components/mixins must use heartbeats to coordinate.
I understand this concept my question is how can they cooperate, It
would be really nice to have a live example involving the use of
heartbeat to get Ids of "only known at runtime component".
The only example I could find about heartbeat is to defer the firing of
an event :
Taken from http://wiki.apache.org/tapestry/Tapestry5SubmitContextComponent
Runnable sendNotification = new Runnable()
{
public void run()
{
_resources.triggerEvent(SELECTED_EVENT, new Object[] {context}, null);
}
};
// When not deferred, don't wait, fire the event now (actually, at the end of the current
// heartbeat). This is most likely because the Submit is inside a Loop and some contextual
// information will change if we defer. Another option might be to wait until the next
// heartbeak?
if (_defer)
_formSupport.defer(sendNotification);
else
_heartbeat.defer(sendNotification);
But If you read the rest of this exemple, _heartbeat.begin,
_heartbeat.end are never called ... Who call them ? What means calling
them ?
>
> I hope this helps. I'd suggest looking into the source for heartbeat's
> implementation as well as what really happens inside form support's
> defer method. You're not alone in your questions and expanded docs on
> this would be helpful.
You're right I think a little dive in the source code would be
refreshing :-)
>
> sincerely,
> chris
>
> PS - irc.freenode.net #tapestry
>
> Michael Courcy wrote:
>> Gabriel Landais a écrit :
>>> Michael Courcy a écrit :
>>>> If you look at this exemple : TreeGridComponent
>>>> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>>>
>>>> a hearbeat.begin is called in beginRender and heartbeat.end is
>>>> called in afterRender but you can never read a call to defer, so
>>>> can you explain why the author of this component call begin and end
>>>> ? I really can't explain myself.
>>> I've based my component on
>>> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
>>> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
>>> really understanding how it heartbeat works... As I don't use defer,
>>> I don't even know if it is useful...
>>> Gabriel
>> But do you see a different hehaviour if you remove this two lines ?
>>>
>>> ---------------------------------------------------------------------
>>> 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
>
>
--
Michael Courcy
http://courcy.blogspot.com
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
For additional commands, e-mail: users-help@tapestry.apache.org
Re: What's heartbeat ?
Posted by Chris Lewis <ch...@bellsouth.net>.
I'm not an expert on this, but I can offer you a real need for defer().
Suppose you have a mixin that attaches some trivial piece of JavaScript
to components that use it; for example, a key logger. As far as the JS,
what you need to do is register a few DOM event handlers on an element -
probably onkeypress or onkeyup, etc. Let's suppose you wrote a class
that creates such objects, and all you need to instantiate them is the
DOM id of the element.
In a simple case all you'd need to do is have your mixin include the
javascript and provide a line (like support.addScript()) to instantiate
the object in JS code - providing the component id, which I think you
can get through something like ComponentResources. Now, if in your
template code you have one component for which you explicitly provide
the DOM id, then your mixin will end up with this id. However there are
situations where you simply can't know the id before hand, and in such
cases you must rely on Tapestry to provide it.
A classic example is looping. If you have a loop that for some reason
creates a variable number of components, to which you'd like to attach
instances of your JS key logger, then you need to get the ids (created
on the fly) from Tapestry. What's more, you can't assk a component for
its id until it has already been assigned one, and the only way to be
sure that your code executes after the assignment happen is to use
Heartbeat#defer.
Now as far as when a heartbeat is created, and when/who must call
start() and end(), I'm not entirely sure. I think that a component whose
behavior interacts with/depends on that of other components/mixins must
use heartbeats to coordinate.
I hope this helps. I'd suggest looking into the source for heartbeat's
implementation as well as what really happens inside form support's
defer method. You're not alone in your questions and expanded docs on
this would be helpful.
sincerely,
chris
PS - irc.freenode.net #tapestry
Michael Courcy wrote:
> Gabriel Landais a écrit :
>> Michael Courcy a écrit :
>>> If you look at this exemple : TreeGridComponent
>>> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>>
>>> a hearbeat.begin is called in beginRender and heartbeat.end is
>>> called in afterRender but you can never read a call to defer, so can
>>> you explain why the author of this component call begin and end ? I
>>> really can't explain myself.
>> I've based my component on
>> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
>> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
>> really understanding how it heartbeat works... As I don't use defer,
>> I don't even know if it is useful...
>> Gabriel
> But do you see a different hehaviour if you remove this two lines ?
>>
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Re: What's heartbeat ?
Posted by Michael Courcy <mi...@gmail.com>.
Gabriel Landais a écrit :
> Michael Courcy a écrit :
>> If you look at this exemple : TreeGridComponent
>> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>
>> a hearbeat.begin is called in beginRender and heartbeat.end is called
>> in afterRender but you can never read a call to defer, so can you
>> explain why the author of this component call begin and end ? I
>> really can't explain myself.
> I've based my component on
> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
> really understanding how it heartbeat works... As I don't use defer, I
> don't even know if it is useful...
> Gabriel
But do you see a different hehaviour if you remove this two lines ?
>
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Michael Courcy
http://courcy.blogspot.com
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Re: What's heartbeat ?
Posted by Gabriel Landais <la...@codelutin.com>.
Steph a écrit :
> Your code Gabriel work as well without heartbeats ... ;-)
>
> Stephane
>
Yes it is ;) Until you use defer, it should be useless. And as I think
that I'll not need it, I remove it heartbeat reference.
Gabriel
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Re: What's heartbeat ?
Posted by Steph <sd...@cariboo-networks.com>.
Your code Gabriel work as well without heartbeats ... ;-)
Stephane
Gabriel Landais a écrit :
> Michael Courcy a écrit :
>> If you look at this exemple : TreeGridComponent
>> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>
>> a hearbeat.begin is called in beginRender and heartbeat.end is called
>> in afterRender but you can never read a call to defer, so can you
>> explain why the author of this component call begin and end ? I
>> really can't explain myself.
> I've based my component on
> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
> really understanding how it heartbeat works... As I don't use defer, I
> don't even know if it is useful...
> Gabriel
>
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Re: What's heartbeat ?
Posted by Michael Courcy <mi...@gmail.com>.
Gabriel Landais a écrit :
> Michael Courcy a écrit :
>> If you look at this exemple : TreeGridComponent
>> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>>
>> a hearbeat.begin is called in beginRender and heartbeat.end is called
>> in afterRender but you can never read a call to defer, so can you
>> explain why the author of this component call begin and end ? I
>> really can't explain myself.
> I've based my component on
> <http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
> and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
> really understanding how it heartbeat works... As I don't use defer, I
> don't even know if it is useful...
> Gabriel
One point for your honesty.
Thanks.
>
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Re: What's heartbeat ?
Posted by Gabriel Landais <la...@codelutin.com>.
Michael Courcy a écrit :
> If you look at this exemple : TreeGridComponent
> http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
>
> a hearbeat.begin is called in beginRender and heartbeat.end is called
> in afterRender but you can never read a call to defer, so can you
> explain why the author of this component call begin and end ? I really
> can't explain myself.
I've based my component on
<http://wiki.apache.org/tapestry/Tapestry5HowToCreateYourOwnComponents>
and <http://wiki.apache.org/tapestry/Tapestry5TreeComponent> without
really understanding how it heartbeat works... As I don't use defer, I
don't even know if it is useful...
Gabriel
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Re: What's heartbeat ?
Posted by Michael Courcy <mi...@gmail.com>.
Yes thanks,
I've done this first of course.
It's a start but it does not bring so much light in my point of view.
For instance :
it does not say what's the difference between calling formSupport.defer
or heartbeat.defer, do you see the difference and the conscequences on
request treatment or event treatment ?
If you look at this exemple : TreeGridComponent
http://tapestry5-treegrid.googlecode.com/svn/trunk/tapestry5-treegrid/src/main/java/org/codelutin/tapestry/components/TreeGrid.java
a hearbeat.begin is called in beginRender and heartbeat.end is called in
afterRender but you can never read a call to defer, so can you explain
why the author of this component call begin and end ? I really can't
explain myself.
What's going on if many components on a page use heartbeat, each
component have its own heartbeat system, or is there a general heartbeat
rythm, and each component register to it through the call to begin, end
and defer ? Can two different heartbeat join and in which circumstances?
Especially if a componnent contains another component ?
Mybe heartbeat is something very simple and the word "heartbeat" make me
think it's bigger but I don't find that so clear when I start to read it
in real components.
Michael
Kalle Korhonen a écrit :
> First result with a google search "tapestry 5 heartbeat":
> http://tapestry.formos.com/nightly/tapestry5/apidocs/org/apache/tapestry/services/Heartbeat.html
>
> Kalle
>
> On 1/6/08, Michael Courcy <mi...@gmail.com> wrote:
>
>> Hi list,
>>
>> As I start to read the code on components I often see heartbeat
>>
>> @Environmental
>> private Heartbeat heartbeat;
>>
>> with heartbeat.begin and heartbeat.end
>>
>> Can someone explain the role of this object and its methods invocations
>> (begin and end) beacause it's not really clear in my mind.
>>
>> Thanks a lot.
>>
>> --
>> Michael Courcy
>> http://courcy.blogspot.com
>>
>>
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>>
>
>
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Re: What's heartbeat ?
Posted by Kalle Korhonen <ka...@gmail.com>.
First result with a google search "tapestry 5 heartbeat":
http://tapestry.formos.com/nightly/tapestry5/apidocs/org/apache/tapestry/services/Heartbeat.html
Kalle
On 1/6/08, Michael Courcy <mi...@gmail.com> wrote:
>
> Hi list,
>
> As I start to read the code on components I often see heartbeat
>
> @Environmental
> private Heartbeat heartbeat;
>
> with heartbeat.begin and heartbeat.end
>
> Can someone explain the role of this object and its methods invocations
> (begin and end) beacause it's not really clear in my mind.
>
> Thanks a lot.
>
> --
> Michael Courcy
> http://courcy.blogspot.com
>
>
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>