model presenter prob. help please

Hello people,



I hope you can help me. It is a very simple problem I have and I'm actually
embarresed bring it up.

I'm trying to link a simple model to it view/presenter pair. Now I can get
it to work sometimes on the most basic models but sometimes not. I think
I've got a blind spot and it's starting to drive me round the bend. Thanks
for you help.



My model has one instance variable number holding 'an integer'.



My presenter is called TransactionShell. The sub-presenter is called
numberPresenter. This is the code:

createComponent

"Create the presenters contained by the receiver"

super createComponents.

numberPresenter := self add: NumberPresenter new name: 'number'



model: aTransaction

"Set the model associated with the receiver"

super model: aTransaction.

numberPresenter model: ( aTransaction aspectValue: #number)





Class method: defaultModel



^Transaction new







Now when I execute' TransactionShell' show in a workspace I get the
following error message:

21:27:40, 13 September 2001: 'UndefinedObject does not understand #model:'

UndefinedObject(Object)>>doesNotUnderstand:

TransactionShell>>model:

TransactionShell(Presenter)>>on:

TransactionShell class(Presenter class)>>on:

TransactionShell class(Presenter class)>>new

TransactionShell class(Shell class)>>create:

TransactionShell class(Presenter class)>>create

TransactionShell class(Presenter class)>>show

UndefinedObject>>{unbound}doIt

CompiledExpression>>value:

SmalltalkWorkspace>>evaluateRange:ifFail:debug:

SmalltalkWorkspace>>evaluateRange:ifFail:

SmalltalkWorkspace>>displayIt

Symbol>>forwardTo:

[] in Command>>value

BlockClosure>>ifCurtailed:

BlockClosure>>ensure:

Command>>value

SmalltalkWorkspaceDocument(Shell)>>performCommand:

CommandQuery>>perform

DelegatingCommandPolicy(CommandPolicy)>>route:

[] in ShellView(View)>>onCommand:

BlockClosure>>ifCurtailed:

BlockClosure>>ensure:

Cursor>>showWhile:

ShellView(View)>>onCommand:

ShellView(View)>>wmCommand:wParam:lParam:

ShellView(View)>>dispatchMessage:wParam:lParam:

[] in InputState>>wndProc:message:wParam:lParam:cookie:

BlockClosure>>ifCurtailed:

ProcessorScheduler>>callback:evaluate:

InputState>>wndProc:message:wParam:lParam:cookie:

ShellView>>translateAccelerator:

ShellView>>preTranslateKeyboardInput:

ShellView(View)>>preTranslateMessage:

InputState>>preTranslateMessage:

InputState>>pumpMessage:

InputState>>loopWhile:

InputState>>mainLoop

[] in InputState>>forkMain

ExceptionHandler(ExceptionHandlerAbstract)>>markAndTry

[] in ExceptionHandler(ExceptionHandlerAbstract)>>try:

BlockClosure>>ifCurtailed:

BlockClosure>>ensure:

ExceptionHandler(ExceptionHandlerAbstract)>>try:

BlockClosure>>on:do:

[] in BlockClosure>>newProcess







Jaskooner

Jaskooner,

> createComponent
>   "Create the presenters contained by the receiver"
>   super createComponents.
>   numberPresenter := self add: NumberPresenter new name: 'number'

Your #createComponents method is called #createCompent (singular).  Unless
it's a typo in your post, adding the s should fix it.

Have a good one,

Bill

--
Wilhelm K. Schwab, Ph.D.
[hidden email]

"Bill Schwab" <[hidden email]> wrote in message news:<9nr76g$9gs2p$[hidden email]>...
If that doesn't solve it, do you actually have a getter and setter in
your model called #number and #number: - you try to connect to those
in your #model: method

Ted

Thank you for you reply Bill and Ted,

The problem was I created createComponent (singular) rather than
createComponents (plural) and not see it. I do this from time to time
unfortunetly.

Another wee prob that very similar.

I have my model instance variable number linked to my numberPresenter linked
to my view (This is a very simple example just to get the mechanism into my
head).

The problem I have is to update my numberPresenter when the model instance
variable number changes. I have tried nearly every example I have browsed
for event triggers etc but I am making a obvious mistake somewhere.

Here is my code.

model

number: aInteger
    "Set the value of receivers number instance to the argument, aIntger"

    number := aInteger.
    self trigger: #numberChange


presenter

createComponents

    super createComponents.
    enterNumberPresenter := self add: NumberPresenter new name:
'enterNumberPresenter'.


createSchematicWiring

    self model when: #numberChange send: #myNumberChange to: self


myNumberChange

    enterNumberPresenter value: (self model number)




Thats it. Appreciate your help


jaskooner"Ted Bracht" <[hidden email]> wrote in message
news:[hidden email]...
> "Bill Schwab" <[hidden email]> wrote in message
news:<9nr76g$9gs2p$[hidden email]>...
> > Jaskooner,
> >
> > > createComponent
> > >   "Create the presenters contained by the receiver"
> > >   super createComponents.
> > >   numberPresenter := self add: NumberPresenter new name: 'number'
> >
> > Your #createComponents method is called #createCompent (singular).
Unless

> I have my model instance variable number linked to my numberPresenter
> linked to my view (This is a very simple example just to get the mechanism
> into my head).
>
> The problem I have is to update my numberPresenter when the model instance
> variable number changes. I have tried nearly every example I have browsed
> for event triggers etc but I am making a obvious mistake somewhere.

I can't see anything obviously in error in you code, although
#createSchematicWiring should reall do a super send first but it's absence
won't matter in this case.

There is one method that you haven't mentioned, your Presenter
class>>defaultModel method?  Along those lines, you are sure that the
Presenter's model is an instance of your Model class and that this is the
instance whose #number instance variable you are changing.

One other thing to check is that you've used exactly the same name for the
NumberPresenter in the #createComponents method and for the NumberPresenter
resource when you created the view in the ViewComposer.  A different name
doesn't raise any errors but just results in the view never being updated
when expected.

Ian

Hi

I manged to solve the problem. It wasn't major just a problem in my logic.
Thanks for your help.


Jas

"Ian Bartholomew" <[hidden email]> wrote in message
news:9o0hia$a2jmo$[hidden email]...
> > I have my model instance variable number linked to my numberPresenter
> > linked to my view (This is a very simple example just to get the
mechanism
> > into my head).
> >
> > The problem I have is to update my numberPresenter when the model
instance
> > variable number changes. I have tried nearly every example I have
browsed NumberPresenter
> resource when you created the view in the ViewComposer.  A different name
> doesn't raise any errors but just results in the view never being updated
> when expected.
>
> Ian
>
>
>
>