Hi -

I thought I'd use Spec2 transmissions to implement an album exporer. that is, a 
list of albums next to a list of the tracks on that album next to some 
information about the track:

A structure like this: albumlist ==> trackList ==> track details 

I've had no trouble connecting the album list to the track list, but I cannot 
connect the tracklist to a label (or textInput for that matter) to show any 
track details.

I'm using Pharo 11.

**defaultLayout**

^ SpBoxLayout newHorizontal 

add: (albumListPresenter);

add: (trackListPresenter );

add:(writerPresenter);

yourself

**initializePresenters**

albumListPresenter := self newList.

albumListPresenter display: \[ :item | item displayString\]. 

albumListPresenter items: Repository albums.

trackListPresenter := self newList.

trackListPresenter display: \[ :item | item displayString\]. 

writerPresenter := self newLabel.

**connectPresenters** 

"The first transmission works perfectly"

albumListPresenter transmitTo:  trackListPresenter  transform: \[  :anAlbum | 
anAlbum tracks \]. 

"But this similar one does not work - aTrack appears to be null.". 

trackListPresenter transmitTo:  writerPresenter    transform: \[  :aTrack | 
aTrack  writerDetails  \]. 

There are obviously other ways to code this but I thought transmissions would 
be a good fit here yet I can't quite make it work.

Any help appreciated.

Ken

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