That worked a treat - thanks. I was already aware of the threading issues as have developed for the Mac before, but thanks for the heads up
On 19 Mar 2010, at 17:55, WT wrote: > On Mar 19, 2010, at 6:40 PM, Michael Davey wrote: > >> OK, so I have changed the code to show a placeholder image, but I am a >> little uncertain as to how to fetch the images asynchronously. I could >> start a background thread with performSelectorInBackground, but am concerned >> that this would spawn far too many threads - does anyone have any >> suggestions? > > You might want to use an NSOperationQueue. Define NSOperation instances, each > fetching one or more images. For each fetching NSOperation you define, you > should also define a "cleanup" NSOperation, dependent on its associated > fetching one, so that when the fetching one ends, the cleanup one then swaps > the placeholder image out and the fetched images in. Make sure, though, that > this swap happens in the main thread, meaning that the cleanup NSOperation > should invoke a -performSelectorInMainThread method, rather than access the > UI directly. _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
