Updated: Feb 1, 2019
I was fortunate enough to do a little bit of Mac development today. Cocoa was refreshing with Swift, it was like running around an old house I once knew well. Even though I haven't spent time here in awhile, I still felt like I knew where the butter was.
I got through the easy stuff, Cocoa uses NSViewControllers that are embedded in windows. There was no learning curve when it came to creating my UI and an initial state of my app. I added a few labels, and an image well to the middle of the initial view controller.
My goal for this app was something I could use as a tool. I wanted to be able to do my image resizing without specifying the sizes and names at each permutation. So with this store icon converter, I can drag in an image file and pick a disk location for my new app icon assets. Before I would get the icon from my designer, then use Acorn to do the resizing for each app icon device. Instead this Mac app will generate the entire app icon asset and write it to an existing .xcassets for you! It really feels great after the converter promptly handles your project, the app icon is quickly seen in project, and viewable next build.
These are simple resizes from a source image. Some companies will create new icons for each app device. A better solution for the day to to day developer may be creating one asset then converting to conform with .xcassets app icon. At least it was for me.