Alex Jiang

November 11, 2014

ImageIO - could not find ColorSync function [Solved]

Recently I found an undocumented bug in iOS 8 when I tried to generate pdf under UIkit framework. The bug blocks me from generating pdf in a preferred way using UIPrint, so I had to use a more primitve method to generate the pdf in iOS8.

For better understanding this issue, first I will introduce ways of generating PDF in iOS, and why it may become a problem in iOS8 or above.

October 14, 2014

The Nib file

• User interface objects(Visual elements)
• File Owner, placeholder, a controller object that is responsible for contents of nib file.
  • Usually you will want to connect a controller to the nib file, so that controller’s view can be connected with nib’s top-level object
  • However, if you want to break a view into different nib components, then assemble them together in one controller, you can leave this File Owner blank, and load all nibs in your controller.
• First Responder, placeholder, the first object in your app’s responder chain.
  • The UIKit framework automatically set first responder for you

October 12, 2014

View Controller Essentials :

• An instance of a subclass of UIViewController
• It manages a view hierarchy
• It’s responsible for creating view objects, handling events