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  • Dialog class and aspectBuffer

    From [email protected]@21:1/5 to All on Sat Mar 20 04:11:04 2021
    I have a class Guest, which has parameters #isAttending (Boolean) and #person (Person class). Person class has the given names, family name and title.

    Guest UI is a Dialog that contains #isAttending (a checkbox) and Person (a Presenter).

    In Guest>>#model: I have an aspectBuffer to buffer changes. However the changes to person are always written even if I send #cancel. The change to #isAttending is always buffered.

    Is there a way around this? I followed the PersonalMoney example, specifically PersonalAccountTransactionDialog>>#model: where the aspectBuffer is used.

    Vince

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From [email protected]@21:1/5 to All on Tue Mar 23 04:10:03 2021
    I had to override copy. The changes in the Dialog are correctly buffered and discarded when I press 'Cancel' and written to the backing model when I press 'Save'.

    The structure is as follows. The models:

    Model subclass: #Guest
    instanceVariableNames: 'person isAttending'
    classVariableNames: ''
    poolDictionaries: ''
    classInstanceVariableNames: ''

    Model subclass: #Person
    instanceVariableNames: 'title givenNames familyName dateOfBirth'
    classVariableNames: ''
    poolDictionaries: ''
    classInstanceVariableNames: ''

    Guest>>#person
    ^ person ifNil: [ person := Person new ]

    The Ui classes:

    Presenter subclass: #PersonUi
    instanceVariableNames: 'title givenNames familyName dateOfBirth'
    classVariableNames: ''
    poolDictionaries: ''
    classInstanceVariableNames: ''

    Dialog subclass: #NppGuestView
    instanceVariableNames: 'person isAttending'
    classVariableNames: ''
    poolDictionaries: ''
    classInstanceVariableNames: ''

    Guest>>#model: anObject
    | aspectBuffer |

    super model: anObject.
    aspectBuffer := self model.
    self person model: (aspectBuffer aspectValue: #person).
    self isAttending model: (aspectBuffer aspectValue: #isAttending)

    The class comment for AspectBuffer says: "In order to be correctly used with an AspectBuffer, a subject object must be able to be sensibly duplicated using #copy."

    So I implemented the following:

    Guest>>#copy
    ^ self species new
    person: self person copy;
    isAttending: self isAttending copy

    Vince

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)