Posted by Ben Coman on Oct 11, 2013; 3:55pm
URL: https://forum.world.st/Spec-Lists-setting-the-selection-tp4713776p4713873.html

Benjamin wrote:

Ben

On Oct 11, 2013, at 9:24 AM, [hidden email] wrote:

  

[hidden email] wrote:
    

I found it hard to find documentation on Spec beyond [1],[2],[3], some of which seem to have changed some syntax since they were written. I've been piecing things together to work out how to set the selected item with the simplest example I could. Even though it turns out pretty simple, I thought I'd share in case it was useful for others that haven't dipped their toes into Spec yet.

ComposableModel subclass: #TestSpec
instanceVariableNames: 'list text'
classVariableNames: ''
poolDictionaries: ''
category: 'BTCPlay'

TestSpec >> initializeWidgets
self instantiateModels: #( #list #ListModel ).

TestSpec >> getList
^list

TestSpec class >> mySpecLayout
<spec:#default>
^ SpecLayout composed
add:#getList ;
yourself.

Then from Workspace
x := (TestSpec new openWithSpec ; yourself).
x getList items: { 1 . 2 . 3 . 4}.
x getList setSelectedItem: 2.

cheers -ben

[1] hal.inria.fr/hal-00759030/PDF/Spec-IWST12-Final.pdf‎
[2] https://ci.inria.fr/pharo-contribution/job/PharoForTheEnterprise/lastSuccessfulBuild/artifact/Spec/Spec.pier.pdf 
[3] http://hal.inria.fr/docs/00/70/80/67/PDF/SpecTechReport.pdf



      

So here is the same thing with TreeModel.

ComposableModel subclass: #TestSpec2
  instanceVariableNames: 'tree'
  classVariableNames: ''
  poolDictionaries: ''
  category: 'BTCPlay'

TestSpec2 >> initializeWidgets
  self instantiateModels: #( #tree #TreeModel ).      tree
      childrenBlock: [  :treeItem | self haltOnce. (treeItem isKindOf: Association) ifTrue: [ treeItem value ] ifFalse: [ {} ] ].

TestSpec2 >> getTree
  ^tree

TestSpec2 class >> mySpecLayout
  <spec:#default>
  ^ SpecLayout composed
      add:#getTree ;
      yourself.

Then from Workspace (referring to attached pic)
x := (TestSpec2 new openWithSpec ; yourself).
x getTree roots: {  10 -> {  11. 12 } . 20 -> { 21 . 22 }  } .
x getTree selectedItem.  "<Print It> --> 21 "
x getTree selectedItem: ????

Now how do I select a particular tree item at each level ?
eg. Select 10 and Select 12 ?

cheers, ben
    

There was something missing here at the two levels :)
You can see case 11849[1] fixing the morphic issue
and case 11850 [2] fixing the Spec problem :)
  

Thanks. I'll try it.

Then your example make me think that using association 
to describe the path may lead to an ambiguous situation
  

True. But to clarify things, ListModel suffers the same ambiguity as follows...
x := (TestSpec new openWithSpec ; yourself).
x getList items: { 1 . 2 . 3 . 2 . 4}.
x getList setSelectedItem: 2.

... ListModel and Treemodel should be consistent in this respect.  

Musing further about this...
In the case of a multi-selection ListModel/TreeModel, it is probably reasonable to select all matching.
For a single-selection, I'm not sure.  Considering ListModel first, maybe defaulting to selecting the first matching is reasonable, perhaps with a backup method to select the Nth match. Then again, if the identical object appears in the list multiple times, then #setSelectedItem: might visually highlight all occurances while still reporting only a single object with #selectedItems.  I think part of a test would go...

x getList items: { 1 . 2 . 3 . 2 . 4}.
x getList setSelectedItem: 2.
y := x getList selectedItem.
x getList setSelectedItem: y.
z := x getList selectedItem.
self assert: (y = z)

...which actually works so ListModel is cool in that regard - except maybe an option to visually highlight both 2s would be useful - but as a visual thing maybe that is a handled outside of ListModel.
Actually that should work the same with multi-selection.

x getList items: { 1 . 2 . 3 . 2 . 4}.
x getList setSelectedItems: { 2. 3 }.
y := x getList selectedItems.
x getList setSelectedItems: y.
z := x getList selectedItems.
self assert: (y = z)

Actually it seems there is no #setSelectedItems:.
How then do you save and restore a multi-selection.  e.g....
savedSelection := x getList selectedItems.
"other code that clears/modifies the selection - like refresh for additional items"
 x getList selectedItems: savedSelection.

cheers -ben

Ben

[1] https://pharo.fogbugz.com/default.asp?11849
[2] https://pharo.fogbugz.com/default.asp?11850

  

<Spec-TreeModel-simple-example.png>