21 Jan
2008
21 Jan
'08
12:29 p.m.
Ch Lamprecht wrote:
Lukas Renggli schrieb:
I could work around by creating a new description class and corresponding
MAStringWriter subclass then setting the reference attribute to it:
MASingleOptionDescription new
label: 'Label' ;
reference: MAMyStringDescription new;
selectorAccessor: #myAccessor;
options: [WAPersonManager persons]asDynamicObject;
Then MAPersonModel >> printString returns lastName or something useful.
That way everything works fine and the choices are dynamic (hitting reload in
the browser updates the list)
if an
Object holds a collection of other Objects (like a group of
Persons), and
these (Persons) should not be created/edited but a list to choose
from should be
presented - would a MAMultipleOptionDescription be appropriate? If
so, how can
the options presented be made dynamic.
There are several ways to make properties of descriptions dynamic.
1. Override #description on the instance-side and build your
descriptions programmatically. Don't forget to copy the descriptions,
in case you call super to get modify the default behavior.
2. Pass the property a block that you send #asDynamicObject. See the
senders of this message for examples. This approach is simple and works
in most cases, there are some possible drawbacks however: (1) the
implementation uses a proxy object that might not get properly resolved
in all cases, (2) the proxy object references a block context that
might not be serializeable with your preferred persistency mechanism,
(3) proxies are hard to debug, and (4) from within the block you don't
have access to the described object.
I hope this made sense... Cheers, Christoph
Hmm, maybe it did not...
Is #reference: meant for 'public' use with MA*OptionDescription ?
Thank you, Christoph