You can check out the example I wrote at code.google.com/p/shelves. It does lazy loading of images from the sdcard.
On Tue, Dec 8, 2009 at 11:45 PM, skyhigh <[email protected]> wrote: > I haven't tried to do a lazy background image load like you are doing, > but have done some code that uses a holder/wrapper to store the layout > findViewById which is a nice optimization so that it doesn't have to > call inflate and findViewById again when each row is displayed. My > understanding is that when you do this it will allocate enough views > for each of the rows that are visible on the screen, and then as a row > scrolls off the screen, it will reuse the already initialized view for > a new row that is scrolling onto the screen. > > In looking at your code I think you may have a problem because of the > way that the views for each row get reused when they disappear from > sight. The same view that was used for a row that just disappeared > can be reused for a new row that is appearing as the list scrolls. > Your getView routine is handling this by detecting that the > convertView is non-null when it has already been filled in when this > view was used by a previous row. However you don't have any mechanism > to detect when a view has been reused and is now displaying a > different row and the URL has changed to a different URL while the > background AsyncTask was retrieving the image. By the time the > AsyncTask finishes retrieving the image, the view that it saved the > reference to, in order to set the image, could have been reused to > display a different row in the list. If you can add code to check if > it is still the expected URL prior to setting the image I think it > might solve your problem. If the URL has changed then skip setting > the lazy image on that view, and just add the image to your cache. > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en > -- Romain Guy Android framework engineer [email protected] Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
