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

stelabouras

- (void)loadCameraRollAssetToInstagram:(NSURL*)assetsLibraryURL andMessage:(NSString*)message
{
    NSString *escapedString   = [assetsLibraryURL.absoluteString urlencodedString];
    NSString *escapedCaption  = [message urlencodedString];
    NSURL *instagramURL       = [NSURL URLWithString:[NSString stringWithFormat:@"instagram://library?AssetPath=%@&InstagramCaption=%@", escapedString, escapedCaption]];

    [[UIApplication sharedApplication] openURL:instagramURL];
}

hamzasood

#import <UIKit/UIKit.h>
#import <objc/runtime.h>

// Hook with ObjC runtime functions
%config(generator=internal)

// New methods created below
@interface UIGestureRecognizer ()
+ (void)hs_beginForcingAllNewGestureRecognizersToAllowPencilInput;
+ (void)hs_endForcingAllNewGestureRecognizersToAllowPencilInput;

kaishin

extension NSView {
  var snapshot: NSImage {
    guard let bitmapRep = bitmapImageRepForCachingDisplayInRect(bounds) else { return NSImage() }
    bitmapRep.size = bounds.size
    cacheDisplayInRect(bounds, toBitmapImageRep: bitmapRep)
    let image = NSImage(size: bounds.size)
    image.addRepresentation(bitmapRep)
    return image
  }
}

jspahrsummers

//
// DON'T do this, or else you risk a deadlock (e.g., by accidentally performing it in a different order somewhere)
//

dispatch_async(firstQueue, ^{
  dispatch_sync(secondQueue, ^{
    // code requiring both queues
  });
});

zwaldowski

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<!-- iOS 10, macOS Sierra, and friends bring a new logging subsystem that's
supposed to scale from the kernel, up to frameworks, and up to apps. It defaults
to a more regimented, privacy-focused approach that large apps and complex
systems need.

It, along with Activity Tracing introduced in iOS 8 and macOS Yosemite and the
Console app in macOS Sierra, hope to help you graduate from caveman debugging to

lattner

Swift Concurrency Manifesto

Author: Chris Lattner

Chinese Translation by Jason Yu

Contents

• Introduction
• Overall Vision

ole

import UIKit

/// A validation rule for text input.
public enum TextValidationRule {
    /// Any input is valid, including an empty string.
    case noRestriction
    /// The input must not be empty.
    case nonEmpty
    /// The enitre input must match a regular expression. A matching substring is not enough.
    case regularExpression(NSRegularExpression)

danielmartin

If you work on a Swift project that follows the Model-View-ViewModel (MVVM) architecture or similar, you may want to jump to counterpart in Xcode from your view to your model, and then to your view model. (ie. by using Ctrl+Cmd+Up and Ctrl+Cmd+Down).

You can do this in recent versions of Xcode by setting a configuration default.

From a terminal, just type this command and press Enter:

defaults write com.apple.dt.Xcode IDEAdditionalCounterpartSuffixes -array-add "ViewModel" "View"