Draw line in cocoa

I want to draw line on iP开发者_StackOverflow中文版ad using user points. How can I do that? Kindly reply if you know

For simple 2D graphics you'll want to use Quartz 2D.

This Stackoverflow question has some good examples, and apple provide full documentation here

Also - see this very similar question: How do I draw a line on the iPhone? The accepted answer includes instructions and sample code.