Question

I have items which can have very different sizes. They can contain picture, or two.

I used ListBox inside ScrollViewer, scrolling was wery fast, but initialization was taking time.

I tried to use just ListBox or LongListSelector, I can’t say it works: scrolling is very jumpy, some lags.

What can I use for this items to achieve fast enough initialization and smooth scrolling?

Answer 1

Inorder to overcome the black occurrence on scrolling you need to virtualize your scroll control. For that you should inherit IList and create a Collection of your own similar to ObservableCollection in which you will have to override the default indexer depending on your caching requirement and simultaneously maintain a cache for your items. I feel this might be what you are looking for: http://blogs.msdn.com/b/ptorr/archive/2010/08/16/virtualizing-data-in-windows-phone-7-silverlight-applications.aspx

There is a sample project on that page. Try that out.

I also feel that you are facing this problem http://blog.rsuter.com/?p=258. I guess this will be solved using virtualization itself. For initialization, use lazy loading. Hope it helps