Friedrich Dominicus wrote: 
Bernat Romagosa <tibabenfortlapalanca@gmail.com> writes:

  
ouch, I added a . in the middle, sorry!

elements := #('eins' 'zwei' 'drei' 'vier').
elements
do: [ :element | (Delay forSeconds: 2) wait ]
displayingProgress: [ :element | 'Working on', element asString ].

2014-03-18 9:55 GMT+01:00 Bernat Romagosa
<tibabenfortlapalanca@gmail.com>:

    Without having tried it, I think you're missing a #wait message in
    there:
    
    
    
    elements := #('eins' 'zwei' 'drei' 'vier').
    elements do: [ :element | (Delay forSeconds: 2) wait ].
    
    displayingProgress: [ :element | 'Working on', element asString ].
    
Sorry even with that I do not see the 'Working on ' message.
It's just a progress bar with nothing else. No "Working on" anywhere.

Regards
Friedrich

I'm not sure what the expected result is, but if you debug/step into that code a few times you find yourself in...
    Array(Collection)>>do:displayingProgress:every:

Looking at expression...
     aStringOrBlock isString
I guessed something might be learnt from stepping through...
    elements := #('eins' 'zwei' 'drei' 'vier').
    elements do: [ :element | (Delay forSeconds: 2) wait ] displayingProgress: 'MyProgress'
and indeed progress bar text is updated by the line...
    bar label: aStringOrBlock.

Now stepping through your original script, #label: never seems to be executed
So replacing...
    [ProgressNotification signal: '' extra: (oldLabel := newLabel)]
with...
    [   bar label: newLabel.   
        ProgressNotification signal: '' extra: (oldLabel := newLabel).
    ].
seems to do the trick, although as I said before, I don't know what the expected behaviour is.  Is that what you need?

I've not looked at this code before so I've learnt something new today. In particular, for a while I was wondering purpose ProgressNotification served since tracing through it seemed to do nothing, and then I realised it might be used something like this...
    elements := #('eins' 'zwei' 'drei' 'vier' ).
    [   elements do: [ :element | (Delay forSeconds: 2) wait ]
        displayingProgress: [ :element | 'Working on ', element asString ]
    ] on: ProgressNotification do:
    [     :notice |
          self inform: notice extraParam printString.
          notice resume
    ]

I've logged a case https://pharo.fogbugz.com/f/cases/13101/Progress-bar-progressive-text-update-not-working

cheers -ben