JeOam

Author: https://www.cyanhall.com/

1. The Layer Tree

Core Animation's original name is Layer Kit

Core Animation is a compositing engine; its job is to compose different pieces of visual content on the screen, and to do so as fast as possible. The content in question is divided into individual layers stored in a hierarchy known as the layer tree. This tree forms the underpinning for all of UIKit, and for everything that you see on the screen in an iOS application.

In UIView, tasks such as rendering, layout and animation are all managed by a Core Animation class called CALayer. The only major feature of UIView that isn’t handled by CALayer is user interaction.

There are four hierarchies, each performing a different role:

skyfishjy

/*
 * Copyright (C) 2014 skyfish.jy@gmail.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software

tfrank64

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool {
        // Override point for customization after application launch.
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        
        var nav1 = UINavigationController()
        var first = FirstViewController(nibName: nil, bundle: nil)
        nav1.viewControllers = [first]
        
        var second = SecondViewController(nibName: nil, bundle: nil)
        var nav2 = UINavigationController()

n-b

//
//  NBResponderChainUtilities.h
//  
//  Created by Nicolas @ bou.io on 19/04/13.
//

#import <UIKit/UIKit.h>

@interface UIView (NBResponderChainUtilities)
- (UIView*) nb_firstResponder; // Recurse into subviews to find one that responds YES to -isFirstResponder

joaofranca

- (void)layoutSubviews{
    
    [super layoutSubviews];

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:0.0f];
    
    for (UIView *subview in self.subviews) {