How to draw using Quartz 2D to my ViewController
Posted on 2015-02-09
This is sort of a beginner-level question. I have inherited an iOS project and it is implemented with a few ViewControllers with associated XIB files. The XIB files contain various widgets that are controlled by code in the ViewControllers (which I think is the standard way of doing this).
However, I need to do some custom drawing (rectangles, lines, circles, text) in between the widgets, and I'd like to use the Quartz 2D library to do this. I've never used Quartz2D, and most of the sample code I find is centered around the View, not the ViewController.
Most of it has to do with implementing the "drawRect" method of your View. However, my ViewController does not have a "drawRect" function, as far as I can tell. Is there a way I can implement a "drawRect" function on my ViewController or whatever View it is controlling?
*** addendum: I have researched a bit further and reminded myself that the operational UIView is a property of the UIViewController, and it seems like UIView is created automatically by the application and bundled together with my XIB and ViewController (I think we selected "also create XIB" when we were creating a ViewController, so the UIView is implied?). I don't see where this default UIView instantiation occurs. But I assume the way to draw to it is to subclass it?
If so, what is the *cleanest* way to subclass this UIView and get access to drawRect while maintaining the connection to the existing ViewController and XIB (or storyboard)? I inherited the project and this change needs to be low-impact.
Thanks for any help/thoughts.