After a little Cocoa break I’m back, while continuing through the book I seemed to have forgotten some stuff already, not good.
So, next up, Keyboard Events.
This chapter explains how the events are used for handling keystrokes as well as the first responder concept. The first responder being the active view element (button, text area,…) and there’s a whole mechanism working in the background when the first responder changes. Not a lot of ground breaking material here, probably the most important piece of code here is an example of how to code the fuzzy blue box around an active custom view.
Chapter 20, Drawing text with attributes.
Here we are taught how to show strings in various formats, not that interesting. One nice feature however is that all the drawing commands you write can be converted into PDF by the AppKit framework.
Chapter 21, Pasteboards and Nil-Targeted actions.
The clipboard in Windows, pasteboard in OS X. Different name, same concept, although I’ve never read about it in any .Net book I’ve seen but you know what it does :). What you need to remember from this chapter is that you can do a lazy paste. Meaning that you don’t have to put it in the clip errr pasteboard when the user presses the copy command. You can wait until he presses paste, very valuable if you’re working with large quantities of data.
Nil targeted actions are best explained with an example. You can set the selector (method signature for .net people) of a menu item to anything you want, say removeEmployee:, when the menu item’s target is nil and the menu item is invoked, it will traverse the responder tree until someone acts upon it.
Nothing fancy was covered in these past chapters, but you need to know about these things. I did spend quite some time on the applications, probably because there was a two week pause. For those interested I’ve attached all the source code.
As always, you can get the book here
TypingTutor – Chapter 19.zip (46.44 kb)
TypingTutor – Chapter 20.zip (53.47 kb)
TypingTutor – Chapter 20 Challenge 1.zip (53.73 kb)
TypingTutor – Chapter 20 Challenge 2.zip (57.89 kb)
TypingTutor – Chapter 21.zip (53.58 kb)