Component initModel() order (design issue?)
Hi, I was just trying to create a component of my own which - in some of my pages - is created without a model. In the initModel() method I would then call super.initModel() and wrap the resulting model for use in a child component. The problem is the initialization order: The child model's initModel() gets called first, the parent (my custom component) does not yet have a model (getModelImpl() returns null) so it goes up farther in the component hierarchy and retrieves a wrong model. Looking at the Component source code (Wicket 1.4.1) I see a commented out line where initModel() used to to call the parent getModel() instead of getModelImpl(). There's also a comment explaining that doing so would "initialize many inbetween completely useless models". Well, not so useless for what I am trying to do I guess. So, from my perspective this looks like a bug that causes necessary initialization to be bypassed. Obviously though it was done like that on purpose, so I decided to put the issue up here instead of filing a bug report. Has anyone else run into similar issues? Would it really be so bad to just call getModel()? Cheers Edmund -- Liland ...does IT better Liland IT GmbH Software Architekt email: edmund.urb...@liland.at office: +43 (0)463 220111 | fax: +43 (0)463 220111 33 | mobil: +43 (0)699 122011 16 http://www.Liland.at - To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org
Re: Component initModel() order (design issue?)
The child model's initModel() gets called first
There are no especial ordering programing to initModels calls. Basically
they are called by
public final IModel getDefaultModel()
{
IModel model = getModelImpl();
// If model is null
if (model == null)
{
// give subclass a chance to lazy-init model
model = initModel();
setModelImpl(model);
}
return model;
}
What about your custom component gain an model that implements
IComponentInheritedModel and assign his children default models with the
desired logic? On IComponentInheritedModel you can access your custom
component parent model, and if you use getDefaultModel method, you don't
need to care with initialization ordering too...
On Wed, Sep 30, 2009 at 9:51 AM, Edmund Urbani wrote:
> Hi,
>
> I was just trying to create a component of my own which - in some of my
> pages -
> is created without a model. In the initModel() method I would then call
> super.initModel() and wrap the resulting model for use in a child
> component. The
> problem is the initialization order:
>
> The child model's initModel() gets called first, the parent (my custom
> component) does not yet have a model (getModelImpl() returns null) so it
> goes up
> farther in the component hierarchy and retrieves a wrong model.
>
> Looking at the Component source code (Wicket 1.4.1) I see a commented out
> line
> where initModel() used to to call the parent getModel() instead of
> getModelImpl(). There's also a comment explaining that doing so would
> "initialize many inbetween completely useless models". Well, not so useless
> for
> what I am trying to do I guess.
>
> So, from my perspective this looks like a bug that causes necessary
> initialization to be bypassed. Obviously though it was done like that on
> purpose, so I decided to put the issue up here instead of filing a bug
> report.
>
> Has anyone else run into similar issues?
> Would it really be so bad to just call getModel()?
>
> Cheers
> Edmund
>
> --
> Liland ...does IT better
>
> Liland IT GmbH
> Software Architekt
> email: edmund.urb...@liland.at
>
> office: +43 (0)463 220111 | fax: +43 (0)463 220111 33 | mobil: +43 (0)699
> 122011 16
> http://www.Liland.at
>
> -
> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org
> For additional commands, e-mail: users-h...@wicket.apache.org
>
>
--
Pedro Henrique Oliveira dos Santos
Re: Component initModel() order (design issue?)
You're right, getDefaultModel ensures initialization. I should have suggested
that instead of getModel (which is not available in the component class anymore
in 1.4.x).
However, I did not want to override the initModel() method (and copy most of its
code) just for that. So now I solved it by creating a new wrap model, which I
pass to the child component and which wraps around the parent.getDefaultModel().
public class ComponentWrapModel implements IWrapModel {
private Component component;
public ComponentWrapModel(Component component) { // component = parent
this.component=component;
}
@Override
public IModel getWrappedModel() {
return component.getDefaultModel();
}
}
Here's some more background which should explain why I chose to do this:
I replace form components (eg. Textfield) with custom components (eg.
MyTextfield) to add a few things my application needs to them. The name
MyTextfield is a bit misleading here, because this is actually a subclass of
Panel, and it merely contains a Textfield as a child. Still I wanted to use
MyTextfield as a drop-in replacement, even when used in a form with a
CompoundPropertyModel. This is where things got a little tricky, because the
Textfield would end up trying to retrieve a property model matching its own
wicket:id, when the relevant wicket:id had now become that of MyTextfield.
Anyway I would have expected that wicket ensures the parent component model gets
initialized first, seeing how components generally query their parents when they
don't have a model of their own. And I'm still considering to report this as a
bug in Jira.
Cheers
Edmund
Pedro Santos wrote:
> The child model's initModel() gets called first
> There are no especial ordering programing to initModels calls. Basically
> they are called by
>
> public final IModel getDefaultModel()
> {
> IModel model = getModelImpl();
> // If model is null
> if (model == null)
> {
> // give subclass a chance to lazy-init model
> model = initModel();
> setModelImpl(model);
> }
>
> return model;
> }
> What about your custom component gain an model that implements
> IComponentInheritedModel and assign his children default models with the
> desired logic? On IComponentInheritedModel you can access your custom
> component parent model, and if you use getDefaultModel method, you don't
> need to care with initialization ordering too...
>
> On Wed, Sep 30, 2009 at 9:51 AM, Edmund Urbani wrote:
>
>> Hi,
>>
>> I was just trying to create a component of my own which - in some of my
>> pages -
>> is created without a model. In the initModel() method I would then call
>> super.initModel() and wrap the resulting model for use in a child
>> component. The
>> problem is the initialization order:
>>
>> The child model's initModel() gets called first, the parent (my custom
>> component) does not yet have a model (getModelImpl() returns null) so it
>> goes up
>> farther in the component hierarchy and retrieves a wrong model.
>>
>> Looking at the Component source code (Wicket 1.4.1) I see a commented out
>> line
>> where initModel() used to to call the parent getModel() instead of
>> getModelImpl(). There's also a comment explaining that doing so would
>> "initialize many inbetween completely useless models". Well, not so useless
>> for
>> what I am trying to do I guess.
>>
>> So, from my perspective this looks like a bug that causes necessary
>> initialization to be bypassed. Obviously though it was done like that on
>> purpose, so I decided to put the issue up here instead of filing a bug
>> report.
>>
>> Has anyone else run into similar issues?
>> Would it really be so bad to just call getModel()?
>>
>> Cheers
>> Edmund
>>
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Re: Component initModel() order (design issue?)
why not
class mytextefield extends panel {
public mytextfield {
add(new textfield() { initmodel() { return
mytextfield.this.getdefaultmodel(); }});
}
}
since this is essentially what you want to do - have textfield use the
same model as the panel.
-igor
On Wed, Sep 30, 2009 at 9:47 AM, Edmund Urbani wrote:
> You're right, getDefaultModel ensures initialization. I should have suggested
> that instead of getModel (which is not available in the component class
> anymore
> in 1.4.x).
>
> However, I did not want to override the initModel() method (and copy most of
> its
> code) just for that. So now I solved it by creating a new wrap model, which I
> pass to the child component and which wraps around the
> parent.getDefaultModel().
>
> public class ComponentWrapModel implements IWrapModel {
> private Component component;
> public ComponentWrapModel(Component component) { // component = parent
> this.component=component;
> }
>
> �...@override
> public IModel getWrappedModel() {
> return component.getDefaultModel();
> }
>
> }
>
> Here's some more background which should explain why I chose to do this:
> I replace form components (eg. Textfield) with custom components (eg.
> MyTextfield) to add a few things my application needs to them. The name
> MyTextfield is a bit misleading here, because this is actually a subclass of
> Panel, and it merely contains a Textfield as a child. Still I wanted to use
> MyTextfield as a drop-in replacement, even when used in a form with a
> CompoundPropertyModel. This is where things got a little tricky, because the
> Textfield would end up trying to retrieve a property model matching its own
> wicket:id, when the relevant wicket:id had now become that of MyTextfield.
>
> Anyway I would have expected that wicket ensures the parent component model
> gets
> initialized first, seeing how components generally query their parents when
> they
> don't have a model of their own. And I'm still considering to report this as a
> bug in Jira.
>
> Cheers
> Edmund
>
>
> Pedro Santos wrote:
>> The child model's initModel() gets called first
>> There are no especial ordering programing to initModels calls. Basically
>> they are called by
>>
>> public final IModel getDefaultModel()
>> {
>> IModel model = getModelImpl();
>> // If model is null
>> if (model == null)
>> {
>> // give subclass a chance to lazy-init model
>> model = initModel();
>> setModelImpl(model);
>> }
>>
>> return model;
>> }
>> What about your custom component gain an model that implements
>> IComponentInheritedModel and assign his children default models with the
>> desired logic? On IComponentInheritedModel you can access your custom
>> component parent model, and if you use getDefaultModel method, you don't
>> need to care with initialization ordering too...
>>
>> On Wed, Sep 30, 2009 at 9:51 AM, Edmund Urbani wrote:
>>
>>> Hi,
>>>
>>> I was just trying to create a component of my own which - in some of my
>>> pages -
>>> is created without a model. In the initModel() method I would then call
>>> super.initModel() and wrap the resulting model for use in a child
>>> component. The
>>> problem is the initialization order:
>>>
>>> The child model's initModel() gets called first, the parent (my custom
>>> component) does not yet have a model (getModelImpl() returns null) so it
>>> goes up
>>> farther in the component hierarchy and retrieves a wrong model.
>>>
>>> Looking at the Component source code (Wicket 1.4.1) I see a commented out
>>> line
>>> where initModel() used to to call the parent getModel() instead of
>>> getModelImpl(). There's also a comment explaining that doing so would
>>> "initialize many inbetween completely useless models". Well, not so useless
>>> for
>>> what I am trying to do I guess.
>>>
>>> So, from my perspective this looks like a bug that causes necessary
>>> initialization to be bypassed. Obviously though it was done like that on
>>> purpose, so I decided to put the issue up here instead of filing a bug
>>> report.
>>>
>>> Has anyone else run into similar issues?
>>> Would it really be so bad to just call getModel()?
>>>
>>> Cheers
>>> Edmund
>>>
>
>
> -
> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org
> For additional commands, e-mail: users-h...@wicket.apache.org
>
>
-
To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org
For additional commands, e-mail: users-h...@wicket.apache.org
Re: Component initModel() order (design issue?)
Can't be done, because the component does not yet know its parent during object
initialization. initModel/getDefaultModel needs to be called later, when the
component knows its place in the hierarchy. by giving the child component a
model that obtains the model from its parent (MyTextfield) the call to
getDefaultModel is delayed and it works.
Cheers
Edmund
Igor Vaynberg wrote:
> why not
>
> class mytextefield extends panel {
> public mytextfield {
>add(new textfield() { initmodel() { return
> mytextfield.this.getdefaultmodel(); }});
>}
> }
>
> since this is essentially what you want to do - have textfield use the
> same model as the panel.
>
> -igor
>
> On Wed, Sep 30, 2009 at 9:47 AM, Edmund Urbani wrote:
>> You're right, getDefaultModel ensures initialization. I should have suggested
>> that instead of getModel (which is not available in the component class
>> anymore
>> in 1.4.x).
>>
>> However, I did not want to override the initModel() method (and copy most of
>> its
>> code) just for that. So now I solved it by creating a new wrap model, which I
>> pass to the child component and which wraps around the
>> parent.getDefaultModel().
>>
>> public class ComponentWrapModel implements IWrapModel {
>>private Component component;
>>public ComponentWrapModel(Component component) { // component = parent
>>this.component=component;
>>}
>>
>>@Override
>>public IModel getWrappedModel() {
>>return component.getDefaultModel();
>>}
>>
>> }
>>
>> Here's some more background which should explain why I chose to do this:
>> I replace form components (eg. Textfield) with custom components (eg.
>> MyTextfield) to add a few things my application needs to them. The name
>> MyTextfield is a bit misleading here, because this is actually a subclass of
>> Panel, and it merely contains a Textfield as a child. Still I wanted to use
>> MyTextfield as a drop-in replacement, even when used in a form with a
>> CompoundPropertyModel. This is where things got a little tricky, because the
>> Textfield would end up trying to retrieve a property model matching its own
>> wicket:id, when the relevant wicket:id had now become that of MyTextfield.
>>
>> Anyway I would have expected that wicket ensures the parent component model
>> gets
>> initialized first, seeing how components generally query their parents when
>> they
>> don't have a model of their own. And I'm still considering to report this as
>> a
>> bug in Jira.
>>
>> Cheers
>> Edmund
>>
>>
>> Pedro Santos wrote:
>>> The child model's initModel() gets called first
>>> There are no especial ordering programing to initModels calls. Basically
>>> they are called by
>>>
>>> public final IModel getDefaultModel()
>>> {
>>> IModel model = getModelImpl();
>>> // If model is null
>>> if (model == null)
>>> {
>>> // give subclass a chance to lazy-init model
>>> model = initModel();
>>> setModelImpl(model);
>>> }
>>>
>>> return model;
>>> }
>>> What about your custom component gain an model that implements
>>> IComponentInheritedModel and assign his children default models with the
>>> desired logic? On IComponentInheritedModel you can access your custom
>>> component parent model, and if you use getDefaultModel method, you don't
>>> need to care with initialization ordering too...
>>>
>>> On Wed, Sep 30, 2009 at 9:51 AM, Edmund Urbani wrote:
>>>
Hi,
I was just trying to create a component of my own which - in some of my
pages -
is created without a model. In the initModel() method I would then call
super.initModel() and wrap the resulting model for use in a child
component. The
problem is the initialization order:
The child model's initModel() gets called first, the parent (my custom
component) does not yet have a model (getModelImpl() returns null) so it
goes up
farther in the component hierarchy and retrieves a wrong model.
Looking at the Component source code (Wicket 1.4.1) I see a commented out
line
where initModel() used to to call the parent getModel() instead of
getModelImpl(). There's also a comment explaining that doing so would
"initialize many inbetween completely useless models". Well, not so useless
for
what I am trying to do I guess.
So, from my perspective this looks like a bug that causes necessary
initialization to be bypassed. Obviously though it was done like that on
purpose, so I decided to put the issue up here instead of filing a bug
report.
Has anyone else run into similar issues?
Would it really be so bad to just call getModel()?
Cheers
Edmund
>>
>> -
>> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org
>> For additional co
Re: Component initModel() order (design issue?)
initmodel isnt called until the first getmodel/object call. why would
that happen before the component is added to its parent?
-igor
On Thu, Oct 1, 2009 at 1:03 AM, Edmund Urbani wrote:
> Can't be done, because the component does not yet know its parent during
> object
> initialization. initModel/getDefaultModel needs to be called later, when the
> component knows its place in the hierarchy. by giving the child component a
> model that obtains the model from its parent (MyTextfield) the call to
> getDefaultModel is delayed and it works.
>
> Cheers
> Edmund
>
> Igor Vaynberg wrote:
>> why not
>>
>> class mytextefield extends panel {
>> public mytextfield {
>> add(new textfield() { initmodel() { return
>> mytextfield.this.getdefaultmodel(); }});
>> }
>> }
>>
>> since this is essentially what you want to do - have textfield use the
>> same model as the panel.
>>
>> -igor
>>
>> On Wed, Sep 30, 2009 at 9:47 AM, Edmund Urbani wrote:
>>> You're right, getDefaultModel ensures initialization. I should have
>>> suggested
>>> that instead of getModel (which is not available in the component class
>>> anymore
>>> in 1.4.x).
>>>
>>> However, I did not want to override the initModel() method (and copy most
>>> of its
>>> code) just for that. So now I solved it by creating a new wrap model, which
>>> I
>>> pass to the child component and which wraps around the
>>> parent.getDefaultModel().
>>>
>>> public class ComponentWrapModel implements IWrapModel {
>>> private Component component;
>>> public ComponentWrapModel(Component component) { // component =
>>> parent
>>> this.component=component;
>>> }
>>>
>>> �...@override
>>> public IModel getWrappedModel() {
>>> return component.getDefaultModel();
>>> }
>>>
>>> }
>>>
>>> Here's some more background which should explain why I chose to do this:
>>> I replace form components (eg. Textfield) with custom components (eg.
>>> MyTextfield) to add a few things my application needs to them. The name
>>> MyTextfield is a bit misleading here, because this is actually a subclass of
>>> Panel, and it merely contains a Textfield as a child. Still I wanted to use
>>> MyTextfield as a drop-in replacement, even when used in a form with a
>>> CompoundPropertyModel. This is where things got a little tricky, because the
>>> Textfield would end up trying to retrieve a property model matching its own
>>> wicket:id, when the relevant wicket:id had now become that of MyTextfield.
>>>
>>> Anyway I would have expected that wicket ensures the parent component model
>>> gets
>>> initialized first, seeing how components generally query their parents when
>>> they
>>> don't have a model of their own. And I'm still considering to report this
>>> as a
>>> bug in Jira.
>>>
>>> Cheers
>>> Edmund
>>>
>>>
>>> Pedro Santos wrote:
The child model's initModel() gets called first
There are no especial ordering programing to initModels calls. Basically
they are called by
public final IModel getDefaultModel()
{
IModel model = getModelImpl();
// If model is null
if (model == null)
{
// give subclass a chance to lazy-init model
model = initModel();
setModelImpl(model);
}
return model;
}
What about your custom component gain an model that implements
IComponentInheritedModel and assign his children default models with the
desired logic? On IComponentInheritedModel you can access your custom
component parent model, and if you use getDefaultModel method, you don't
need to care with initialization ordering too...
On Wed, Sep 30, 2009 at 9:51 AM, Edmund Urbani wrote:
> Hi,
>
> I was just trying to create a component of my own which - in some of my
> pages -
> is created without a model. In the initModel() method I would then call
> super.initModel() and wrap the resulting model for use in a child
> component. The
> problem is the initialization order:
>
> The child model's initModel() gets called first, the parent (my custom
> component) does not yet have a model (getModelImpl() returns null) so it
> goes up
> farther in the component hierarchy and retrieves a wrong model.
>
> Looking at the Component source code (Wicket 1.4.1) I see a commented out
> line
> where initModel() used to to call the parent getModel() instead of
> getModelImpl(). There's also a comment explaining that doing so would
> "initialize many inbetween completely useless models". Well, not so
> useless
> for
> what I am trying to do I guess.
>
> So, from my perspective this looks like a bug that causes necessary
> initialization to be bypassed. Obviously though it was done like that on
> purpose, so I decided to put the issue up
