while we're on the topic, i was just having a conversation off-list and it reminded me: we really should do another lcb class. i looked at lcb a couple of times, messed with it, and then said "meh", and moved on.
On Fri, Aug 19, 2022 at 8:56 AM panagiotis m via use-livecode < use-livecode@lists.runrev.com> wrote: > Hello, > > Thank you all for the useful comments. > > I *think* the LCB feature in LC 10 Steven mentioned is the "is > valid" operator, that returns a boolean value indicating whether or not the > image data is valid. > Also, note that in the upcoming releases of LC 10 we will add syntax for > checking if a file/directory exists, so we could check not only image > validity but also image existence in the first place. > > BTW, we have found a workaround for allowing this stack (lazy image > example) to work in LC 9 as well. The updated bundle will probably appear > in your account area in the next couple of days. > > Kind regards, > Panos > -- > > On Fri, 19 Aug 2022 at 01:13, Alex Tweedly via use-livecode < > use-livecode@lists.runrev.com> wrote: > > > > > On 18/08/2022 17:34, Steven Crighton via use-livecode wrote: > > > Hi Mike, > > > > > > I just tested the lazy load example and hit populate and clicked around > > etc and could not trigger an error. > > > > As already confirmed, that problem is fixed in 10. > > > > However, the lazy load example still contains bugs due to race > > conditions, some of which I described in some forum post somewhere (Boy > > do I hate the forums! Surely there's some way to check what posts I have > > done myself). > > > > Thinking about it more, there are other race conditions which are > > perhaps more obscure, but more serious. I know it's only an example, and > > maybe can't be expected to be bulletproof, but as an example of how to > > do Lazy Loading it is (IMHO) really too naive and simplistic. People > > expect to take those examples and just use them. > > > > The obvious race conditions are: > > > > 1. if multiple entries reference the same image, then there is a chance > > the earlier ones never get properly updated (sURLToIndex[pURL] will have > > been overwritten by the next call to onlineImage before the image value > > gets set). > > > > 2. if the user (or anything else) resets the dataContent of the widget > > while there are outstanding "load URL"s, then when the downloadComplete > > is triggered, it will set the image value for some random new item to > > the image of the earlier one. > > > > 3. And if the one which was wrongly set in case 2 above also happens to > > be a URL that occurs multiple time (i.e. case 1 above), then that > > wrongly set image will remain "forever". > > > > Alex. > > _______________________________________________ > > use-livecode mailing list > > use-livecode@lists.runrev.com > > Please visit this url to subscribe, unsubscribe and manage your > > subscription preferences: > > http://lists.runrev.com/mailman/listinfo/use-livecode > > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > -- On the first day, God created the heavens and the Earth On the second day, God created the oceans. On the third day, God put the animals on hold for a few hours, and did a little diving. And God said, "This is good." _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
