Re: Forcing a refresh on a bound control

FROM : David Dunham
DATE : Mon May 19 05:04:29 2008

On 17 May 2008, at 23:18, mmalc Crawford wrote:

>> You can force a KVO notification by sending a will/
>> didChangeValueForKey:
>> pair of messages.
>>

> As has been said on numerous occasions, no, don't do this.



Having missed all the occasions, why not?

I've got a key which is calculated (it's the number of topics which 
are filtered by a search string). As the user types into a search 
field, I need to update this derived value. How else can I let KVO 
know the calculated value has changed, so it can be displayed in the UI?

(BTW, I'm not using Core Data, and need to work on 10.4.)

David Dunham
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