Question

I would like to create a custom NSView that takes a layered approach to painting. I imagine the majority of the layers would be the same width and height as the backing view.

Is it appropriate to use the Core Animation classes like CALayer for this task, even though I don’t expect to need much animation? Is there a more appropriate approach?

To clarify, the view is not meant to be like a canvas in a Photoshop-like application. It more of a data display that should allow for user interaction (selecting, moving, scrolling, etc.)

Answer 1

If it’s display and layout you’re after, I’d say that a CALayer-based architecture is a good choice. For the open source Core Plot framework, we construct all of our graphs and plot elements out of CALayers, and organize them in a regular hierarchy. CALayers are lightweight and use almost identical APIs between Mac and iPhone. They can even be made to respond to touch or mouse events.

For another example of a CALayer-based user interface, my iPhone application‘s entire equation entry interface is composed of CALayers, including the menu that slides up from below. Performance is slightly better than that of my previous UIView-based implementation, but the same code also works within my preliminary desktop version of the application.