Hi Sven,

I had it this way too. Thanks.
Unfortunately my Spec definition was a little different and didn't work out at all. Especially upon resize.

But here is my question regarding embedding this into an "application".

Is this MVC? Here we have Model, View and Controller within one class called Model.... That is exactly what made me think 1000times if this is right and a vital way to go once you want to implement a real workflow.

I looked at all the different approaches.
Just becomming aware that Morph is actually not a class to derive from is something a beginner needs to understand when he just wants to implement a Window using Morphs.... and that is already a major difference to other frameworks where a Window and a Button are part of the same Hierarchy.

Oh wait and what is a MorphicModel then?
Is it a Morph or a Model? Or Both?

I did browse the Squeak/Self Morphic wiki sites and even though most links do not work anymore, I have the feeling that a lot of knowledge her e has already been lost and everybody invents his own wheel currently.

I want to be able to take a LoginModel and have 5 different Morph/View implementations using it. If Spec asks for this kind of Model subclassing, then I do understand that some community members have their problems with it. Not saying that this is the wrong way to go, but I would also rather devide the scpec the model and the controll layer into different classes.

But since there is no example available for this I think one can't even properly discuss that.

For beginners ther eshould be ONE implementation that guides them through all needed aspects of OO programming including UIs.

Sebastian





Am 12.02.2015 um 15:53 schrieb Sven Van Caekenberghe:
So, how hard would it be for a normal user like me, who knows little about the 
Pharo UI or Spec, to write a plain, simple Login dialog ?




It turns out it only takes 3 methods and some boilerplate code that is mostly 
auto generated.

0. Make a subclass of ComposableModel with instance variables for the UI 
elements that we need

ComposableModel subclass: #LoginModel
   instanceVariableNames: 'usernameLabel usernameField passwordLabel 
passwordField'
   classVariableNames: ''
   category: '_UnpackagedPackage'

1. Specify the layout of the UI

LoginModel class>>#defaultSpec
   <spec: #default>

   ^ SpecLayout composed
       newColumn: [ :col |
         col
           newRow: [ :row |
             row
               add: #usernameLabel width: 80;
               add: #usernameField ]
           height: self inputTextHeight;
           newRow: [ :row |
             row
               add: #passwordLabel width: 80;
               add: #passwordField ]
           height: self inputTextHeight ];
        yourself

2. Build the UI elements

LoginModel>>#initializeWidgets
   usernameLabel := self newLabel.
   usernameLabel text: 'Username'.
   usernameField := self newTextInput.
   usernameField autoAccept: true; ghostText: 'j...@acme.com'.
   passwordLabel := self newLabel.
   passwordLabel text: 'Password'; yourself.
   passwordField := self newTextInput.
   passwordField beEncrypted; autoAccept: true; ghostText: '******'.
   self focusOrder add: usernameField; add: passwordField

3. Open the UI as modal dialog

LoginModel class>>#getCredentials
   "self getCredentials"
        
   | login dialog |
   login := self new.
   dialog := login openDialogWithSpec.
   dialog modalRelativeTo: self currentWorld.
   dialog cancelled ifTrue: [ ^ nil ].
   ^ login credentials

X. Some boilerplate code

Auto-generate read accessors for the 4 instance variables.

LoginModel>>#title
   ^ 'Login'

LoginModel>>#initialExtent
   ^ 350 @ 150

LoginModel>>#credentials
   ^ usernameField text -> passwordField text


I think this is pretty cool. I really can't imagine how much easier, how much 
less code this should take.




Let us all learn to use what we have, accept it the way it is, and make it 
better, together.


Sven


BTW: While writing this, following some senders/implementers, I found out that 
in Pharo 4, CredentialsEditor does almost the same thing.


--
Sven Van Caekenberghe
Proudly supporting Pharo
http://pharo.org
http://association.pharo.org
http://consortium.pharo.org



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