Hi, On Wed, Jan 28, 2015 at 1:59 PM, Werner Lehmann < lehm...@media-interactive.de> wrote:
> Robert, > > I think Tomas is right, load your thumbnails on demand when updateItem is > called for an item with missing thumbnail. You say that the cell of a > visible item gets reused for another item. If that is the case I guess that > the item is "moved" to another cell. Wouldn't it be possible to have an > image property on your items and the lazy loading is done on the item, > triggered when the item is passed to updateItem of any cell? That That is exactly what I have implemented but the problem is as described above - Too many non-visible images are loaded (I could probably live with that for a while) - I have yet to find a criterion to decide an image is no longer needed and thus its loading job needs to be removed from the job stack (see below) > should trigger the demand-loading and it would be robust against the > tableview exchanging cells for individual items. > As to the question when to start or stop lazy loading for items, I would > add the load-demands to a stack. Each time the image for a new item is > requested it is put to the top of the stack and you have one or more > threads processing items on the stack (LIFO). An an image is requested > which is already on the stack move it to the top of the stack. If an item > is removed from a cell remove it from the stack. That should do it. > > That's what I am doing already. Regards, Robert Werner > > On 28.01.2015 09:30, Robert Krüger wrote: > >> Doesn't help. The patterns of this property being changed are just as >> unusable for my purposes as with the other approaches (e.g. I can clearly >> see that item is set to a different value for a cell that is still >> visible, >> > ... > > -- Robert Krüger Managing Partner Lesspain GmbH & Co. KG www.lesspain-software.com