Doing high-performance scrolling is a hard problem. You just can't do it in HTML, at all.
Native code is not a silver bullet. If you're implementing a table view cell, the newbie approach is to just put subviews on the cell for each slice of content. This performs horribly because the graphics card has to composite all the sublayers while you're scrolling.
The faster approach, as he alludes to, is to do everything in one view, using pen operations to move around and blit each section. If you're serious about smooth scrolling, this is what you have to do. Tweetie was famous for its smooth scrolling, for example; it's because Loren Brichter used this approach.
Of course, if you're coming from the web/css world, doing everything with pen operations seems incredibly foreign and backwards. But you get good at it quickly. And it's worth it, UX-wise.
> Doing high-performance scrolling is a hard problem. You just can't do it in HTML, at all.
Not necessarily. Especially with Apple adding momentum scrolling to Mobile Safari in iOS 5. I have no problem smoothly scrolling through tables hundreds of rows long.
Doing high-performance scrolling is a hard problem. You just can't do it in HTML, at all.
Native code is not a silver bullet. If you're implementing a table view cell, the newbie approach is to just put subviews on the cell for each slice of content. This performs horribly because the graphics card has to composite all the sublayers while you're scrolling.
The faster approach, as he alludes to, is to do everything in one view, using pen operations to move around and blit each section. If you're serious about smooth scrolling, this is what you have to do. Tweetie was famous for its smooth scrolling, for example; it's because Loren Brichter used this approach.
Of course, if you're coming from the web/css world, doing everything with pen operations seems incredibly foreign and backwards. But you get good at it quickly. And it's worth it, UX-wise.