2017-04-01 17:48 GMT+03:00 Peter Uhnak <i.uhnak@gmail.com>:

Hi,

I wanted to point you to the new Spec book ( http://files.pharo.org/books-pdfs/spec/2017-01-23-SpecBooklet.pdf ), but apprently it's not there.

Many Spec widgets have examples accompanying them, so always check class side (not for all though). For TreeModel you can see couple there - good for playing around; e.g.

exampleWithNoSpecifiedNodes
�� "self exampleWithNoSpecifiedNodes"
�� TreeModel new
�� roots: (1 to: 5);
�� childrenBlock: [ :item | 1+item to: 5+item ];
�� openWithSpec

You specify the initial data (root nodes) via the `roots:` message.
The `childrenBlock:` then specifies how one would retrieve data given a particular node; note that this�� applies to _any node_, not just the root ones; so you can have potentially infinitely deep trees.

A more complex example could be this (this is awful code for demonstration only ;):

TreeModel new
�� roots: {#parent. #childless. 20. #root -> #(a b c)};
�� childrenBlock: [ :item |
�� item isSymbol ifTrue: [
�� item = #parent
�� ifTrue: [ #(child1 child2) ]
�� ifFalse: [ #() ]
�� ] ifFalse: [
�� item isNumber
�� ifTrue: [ {item + 2. item ** 2} ]
�� ifFalse: [ "association" item value ]
�� ]
�� ];
�� openWithSpec

Peter

On Sat, Apr 01, 2017 at 06:49:41AM -0700, chrismihaylyk wrote:
> Hi!
>
> Could anyone explain me how works childrenBlock: method from TreeModel?
> step-by-step.
> What data it operates? How makes a result?
>
> Thanks a lot? Khrystyna.
>
>
>
>
>
> --
> View this message in context: http://forum.world.st/How-childrenBlock-in-TreeModel-works-tp4940884.html
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>