Unable to execute example code from "The Spec UI Framework" Book
Hello, I'm just getting into Pharo, and am trying to do the example 'tutorial' UI programs in chapter 2 of The Spec UI Framework book. I have a special interest in end user GUI interfaces for programs. I enter the first example code as written and the methods are all accepted without errors. And yes, I did generate the accessors. However , on attempting to execute the code at the bottom of page 6 from the latest Spec UI Framework book, | ui | ui := CustomerSatisfaction newopenWithSpec. ui close. this error message appears, no UI image appears of course. "SubclassResponsibility:CustomerSatisfaction class had the subclass responsibility to implement #defaultSpec" ====== Not only don't I understand the message, but it implies I have to write something called #defaultSpec !, which is not mentioned in the tutorial. Any help appreciated, Yours, -- Cheers, Brett
On 21 March 2018 at 03:12, dragoncity <dragoncitybrett@gmail.com> wrote:
Hello, I'm just getting into Pharo, and am trying to do the example 'tutorial' UI programs in chapter 2 of The Spec UI Framework book. I have a special interest in end user GUI interfaces for programs. I enter the first example code as written and the methods are all accepted without errors. And yes, I did generate the accessors.
However , on attempting to execute the code at the bottom of page 6 from the latest Spec UI Framework book,
| ui |
ui := CustomerSatisfaction newopenWithSpec.
ui close.
this error message appears, no UI image appears of course.
"SubclassResponsibility:CustomerSatisfaction class had the subclass responsibility to implement #defaultSpec"
======
Not only don't I understand the message, but it implies I have to write something called #defaultSpec !, which is not mentioned in the tutorial.
CustomerSatisfaction is a subclass of ComposableModel (ComposablePresenter in Pharo 7). If you have a look at the implementation of #defaultSpec in ComposableModel or ComposablePresenter (depending on which version of Pharo you are using) it says that it is up to subclasses to implement the method (#subclassResponsibility). Since you haven't defined it (yet), the call to #defaultSpec uses the inherited definition from ComposableModel, which raises the error you are seeing. CustomerSatisfaction class>>defaultSpec is on page 6 of my version of the booklet, dated Feb 6, 2107. Cheers, Alistair
I had already defined & accepted defaultSpec , as per page 6. Attached is my CustomerSatisfaction.st file : I assume Pharo will suck it back in ! On 21/03/18 17:55, Alistair Grant wrote:
On 21 March 2018 at 03:12, dragoncity <dragoncitybrett@gmail.com> wrote:
Hello, I'm just getting into Pharo, and am trying to do the example 'tutorial' UI programs in chapter 2 of The Spec UI Framework book. I have a special interest in end user GUI interfaces for programs. I enter the first example code as written and the methods are all accepted without errors. And yes, I did generate the accessors.
However , on attempting to execute the code at the bottom of page 6 from the latest Spec UI Framework book,
| ui |
ui := CustomerSatisfaction newopenWithSpec.
ui close.
this error message appears, no UI image appears of course.
"SubclassResponsibility:CustomerSatisfaction class had the subclass responsibility to implement #defaultSpec"
======
Not only don't I understand the message, but it implies I have to write something called #defaultSpec !, which is not mentioned in the tutorial. CustomerSatisfaction is a subclass of ComposableModel (ComposablePresenter in Pharo 7). If you have a look at the implementation of #defaultSpec in ComposableModel or ComposablePresenter (depending on which version of Pharo you are using) it says that it is up to subclasses to implement the method (#subclassResponsibility). Since you haven't defined it (yet), the call to #defaultSpec uses the inherited definition from ComposableModel, which raises the error you are seeing.
CustomerSatisfaction class>>defaultSpec is on page 6 of my version of the booklet, dated Feb 6, 2107.
Cheers, Alistair
-- Cheers, Brett
On 21 March 2018 at 08:37, dragoncity <dragoncitybrett@gmail.com> wrote:
I had already defined & accepted defaultSpec , as per page 6.
Attached is my CustomerSatisfaction.st file : I assume Pharo will suck it back in !
You've defined this as an instance method, not a class method. If what I've said doesn't make sense, let us know and we can point you to a description (which I don't have handy). One tip: Assuming you're using Pharo 6, in the System Browser, roughly in the middle is a "Class" button. Pressing that will show you the class methods. HTH, Alistair
On 21/03/18 17:55, Alistair Grant wrote:
On 21 March 2018 at 03:12, dragoncity <dragoncitybrett@gmail.com> wrote:
Hello, I'm just getting into Pharo, and am trying to do the example 'tutorial' UI programs in chapter 2 of The Spec UI Framework book. I have a special interest in end user GUI interfaces for programs. I enter the first example code as written and the methods are all accepted without errors. And yes, I did generate the accessors.
However , on attempting to execute the code at the bottom of page 6 from the latest Spec UI Framework book,
| ui |
ui := CustomerSatisfaction newopenWithSpec.
ui close.
this error message appears, no UI image appears of course.
"SubclassResponsibility:CustomerSatisfaction class had the subclass responsibility to implement #defaultSpec"
======
Not only don't I understand the message, but it implies I have to write something called #defaultSpec !, which is not mentioned in the tutorial.
CustomerSatisfaction is a subclass of ComposableModel (ComposablePresenter in Pharo 7). If you have a look at the implementation of #defaultSpec in ComposableModel or ComposablePresenter (depending on which version of Pharo you are using) it says that it is up to subclasses to implement the method (#subclassResponsibility). Since you haven't defined it (yet), the call to #defaultSpec uses the inherited definition from ComposableModel, which raises the error you are seeing.
CustomerSatisfaction class>>defaultSpec is on page 6 of my version of the booklet, dated Feb 6, 2107.
Cheers, Alistair
-- Cheers, Brett
You've defined this as an instance method, not a class method Thanks for that observation! On closer read indeed I had missed the 'class' word in the defaultSpec text on page 6, it took a little fiddling to get a Class method defined. Its 'almost' working :-) When I run the |ui | ... etc.... from a Playground, I don't get a working UI Form, but I get a correctly defined static image layout of the form under 'Morph' IN the Playground. I expected the CustomerSatisfaction UI form to appear as a independent item on the Pharo 'world'. Now what am I doing wrong ? :-) On 21/03/18 19:02, Alistair Grant wrote:
On 21 March 2018 at 08:37, dragoncity <dragoncitybrett@gmail.com> wrote:
I had already defined & accepted defaultSpec , as per page 6.
Attached is my CustomerSatisfaction.st file : I assume Pharo will suck it back in ! You've defined this as an instance method, not a class method.
If what I've said doesn't make sense, let us know and we can point you to a description (which I don't have handy). One tip: Assuming you're using Pharo 6, in the System Browser, roughly in the middle is a "Class" button. Pressing that will show you the class methods.
HTH, Alistair
On 21/03/18 17:55, Alistair Grant wrote:
On 21 March 2018 at 03:12, dragoncity <dragoncitybrett@gmail.com> wrote:
Hello, I'm just getting into Pharo, and am trying to do the example 'tutorial' UI programs in chapter 2 of The Spec UI Framework book. I have a special interest in end user GUI interfaces for programs. I enter the first example code as written and the methods are all accepted without errors. And yes, I did generate the accessors.
However , on attempting to execute the code at the bottom of page 6 from the latest Spec UI Framework book,
| ui |
ui := CustomerSatisfaction newopenWithSpec.
ui close.
this error message appears, no UI image appears of course.
"SubclassResponsibility:CustomerSatisfaction class had the subclass responsibility to implement #defaultSpec"
======
Not only don't I understand the message, but it implies I have to write something called #defaultSpec !, which is not mentioned in the tutorial. CustomerSatisfaction is a subclass of ComposableModel (ComposablePresenter in Pharo 7). If you have a look at the implementation of #defaultSpec in ComposableModel or ComposablePresenter (depending on which version of Pharo you are using) it says that it is up to subclasses to implement the method (#subclassResponsibility). Since you haven't defined it (yet), the call to #defaultSpec uses the inherited definition from ComposableModel, which raises the error you are seeing.
CustomerSatisfaction class>>defaultSpec is on page 6 of my version of the booklet, dated Feb 6, 2107.
Cheers, Alistair
-- Cheers, Brett
-- Cheers, Brett
dragoncity-2 wrote
When I run the
|ui | ... etc.... from a Playground, I don't get a working UI Form, but I get a correctly defined static image layout of the form under 'Morph' IN the Playground.
I expected the CustomerSatisfaction UI form to appear as a independent item on the Pharo 'world'.
Now what am I doing wrong ? :-)
I think you want "Do It" instead of "Do It and Go" ----- Cheers, Sean -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
Have you left in that ui close statement that was in your first post? I tried you code and it worked fine - but if you issue a close you'll have nothing to see! -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
Thank you -- of course ! I had that "ui close" in my code !!! , I'd expected the form to take control until I exited the form itself and had not considered the code would 'fall straight through' to the 'ui close' The example form now displays on Pharo's World and is active as expected.
From my experience with trying to get this example working, I think the chapter needs a bit of expansion & more explanation about some features used. The Class method creation verse the instance methods being an example. I guess the authors assume most people will have worked with Pharo without jumping straight to the GUI interfacing !!
Thank you all for your help, getting this example running is a very important step to understanding Pharo's UI. -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
On Thu, Mar 22, 2018 at 1:41 AM, brett <dragoncitybrett@gmail.com> wrote:
Thank you -- of course ! I had that "ui close" in my code !!! , I'd expected the form to take control until I exited the form itself and had not considered the code would 'fall straight through' to the 'ui close'
The example form now displays on Pharo's World and is active as expected.
From my experience with trying to get this example working, I think the chapter needs a bit of expansion & more explanation about some features used. The Class method creation verse the instance methods being an example. I guess the authors assume most people will have worked with Pharo without jumping straight to the GUI interfacing !!
Indeed. We cannot add Pharo by example in all the books we write :)
Thank you all for your help, getting this example running is a very important step to understanding Pharo's UI.
-- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
at the end of the fifth page " The widgets have now been defined and configured, but their placement in the UI has not yet been specified. This is the role of the class side method defaultSpec . " CustomerSatisfaction class >> defaultSpec ^ SpecLayout composed newRow: [ :row | row add: #buttonHappy; add: #buttonNeutral; add: #buttonBad ] origin: 0 @ 0 corner: 1 @ 0.7; newRow: [ :row | row add: #screen ] origin: 0 @ 0.7 corner: 1 @ 1; yourself 2018-03-21 5:12 GMT+03:00 dragoncity <dragoncitybrett@gmail.com>:
Hello, I'm just getting into Pharo, and am trying to do the example 'tutorial' UI programs in chapter 2 of The Spec UI Framework book. I have a special interest in end user GUI interfaces for programs. I enter the first example code as written and the methods are all accepted without errors. And yes, I did generate the accessors.
However , on attempting to execute the code at the bottom of page 6 from the latest Spec UI Framework book,
| ui |
ui := CustomerSatisfaction newopenWithSpec.
ui close.
this error message appears, no UI image appears of course.
"SubclassResponsibility:CustomerSatisfaction class had the subclass responsibility to implement #defaultSpec"
======
Not only don't I understand the message, but it implies I have to write something called #defaultSpec !, which is not mentioned in the tutorial.
Any help appreciated,
Yours,
-- Cheers, Brett
participants (7)
-
Alistair Grant -
brett -
dragoncity
-
kmo -
Sean P. DeNigris -
Stephane Ducasse -
Yuriy Babah