originell

Analysis of Apple’s rubber band scrolling

January 6, 2013

I recently saw a post on Twitter from @chpwn that described the alogorithm that Apple uses for its “rubber band” or “bungee” scrolling.

b = (1.0 – (1.0 / ((x * c / d) + 1.0))) * d

carlosefonseca

#!/usr/bin/env bash

# obtains all data tables from database
TS=`sqlite3 $1 "SELECT tbl_name FROM sqlite_master WHERE type='table' and tbl_name not like 'sqlite_%';"`

# exports each table to csv
for T in $TS; do

sqlite3 $1 <<!
.headers on

eladb

- (void)setupCamera
{
    self.coreImageContext = [CIContext contextWithOptions:nil];

    // session
    self.cameraSession = [[AVCaptureSession alloc] init];
    [self.cameraSession setSessionPreset:AVCaptureSessionPresetPhoto];
    [self.cameraSession commitConfiguration];
    
    // input

nicktoumpelis

git clean -xfd
git submodule foreach --recursive git clean -xfd
git reset --hard
git submodule foreach --recursive git reset --hard
git submodule update --init --recursive

nicklockwood

Hacking UIView animation blocks for fun and profit

In this article, I'm going to explore a way that we can create views that implement custom Core Animation property animations in a natural way.

As we know, layers in iOS come in two flavours: Backing layers and hosted layers. The only difference between them is that the view acts as the layer delegate for its backing layer, but not for any hosted sublayers.

In order to implement the UIView transactional animation blocks, UIView disables all animations by default and then re-enables them individually as required. It does this using the actionForLayer:forKey: method.

Somewhat strangely, UIView doesn't enable animations for every property that CALayer does by default. A notable example is the layer.contents property, which is animatable by default for a hosted layer, but cannot be animated using a UIView animation block.

ZevEisenberg

osascript -e 'tell application "iOS Simulator" to quit'
osascript -e 'tell application "Simulator" to quit'
xcrun simctl erase all

brandonscript

// Requires macros:

#define RADIANS_TO_DEGREES(radians) ((radians) * (180.0 / M_PI))
#define DEGREES_TO_RADIANS(angle) (angle / 180.0 * M_PI)

- (UIImage *)imageRotatedByDegrees:(CGFloat)degrees
{
    // calculate the size of the rotated view's containing box for our drawing space
    UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0,0,self.size.width, self.size.height)];
    CGAffineTransform t = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(degrees));

ffried

extension UIImage {
    public func imageRotatedByDegrees(degrees: CGFloat) -> UIImage {
        let radiansToDegrees: (CGFloat) -> CGFloat = {
            return $0 * (180.0 / CGFloat(M_PI))
        }
        let degreesToRadians: (CGFloat) -> CGFloat = {
            return $0 / (180.0 * CGFloat(M_PI))
        }
        
        // calculate the size of the rotated view's containing box for our drawing space

robnadin

//
//  DetailViewController.swift
//  TransitionCoordinator
//
//  Created by Rob Nadin on 15/02/2015.
//  Copyright (c) 2015 Rob Nadin. All rights reserved.
//

import UIKit

AliSoftware

// #!Swift-1.1
import Foundation


// MARK: - (1) classes

// Solution 1:
//  - Use classes instead of struct
// Issue: Violate the concept of moving model to the value layer
//        http://realm.io/news/andy-matuschak-controlling-complexity/