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@steipete
steipete / PSPDFUIKitMainThreadGuard.m
Last active May 27, 2024 12:11
This is a guard that tracks down UIKit access on threads other than main. This snippet is taken from the commercial iOS PDF framework http://pspdfkit.com, but relicensed under MIT. Works because a lot of calls internally call setNeedsDisplay or setNeedsLayout. Won't catch everything, but it's very lightweight and usually does the job.You might n…
// Taken from the commercial iOS PDF framework http://pspdfkit.com.
// Copyright (c) 2014 Peter Steinberger, PSPDFKit GmbH. All rights reserved.
// Licensed under MIT (http://opensource.org/licenses/MIT)
//
// You should only use this in debug builds. It doesn't use private API, but I wouldn't ship it.
// PLEASE DUPE rdar://27192338 (https://openradar.appspot.com/27192338) if you would like to see this in UIKit.
#import <objc/runtime.h>
#import <objc/message.h>
import lldb
import re
import shlex
# This script allows Xcode to selectively ignore Obj-C exceptions
# based on any selector on the NSException instance
def getRegister(target):
if target.triple.startswith('x86_64'):
return "rdi"
/**
Provides the ability to verify key paths at compile time.
If "keyPath" does not exist, a compile-time error will be generated.
Example:
// Verifies "isFinished" exists on "operation".
NSString *key = SQKeyPath(operation, isFinished);
// Verifies "isFinished" exists on self.
@gruber
gruber / Liberal Regex Pattern for Web URLs
Last active October 10, 2025 20:23
Liberal, Accurate Regex Pattern for Matching Web URLs
The regex patterns in this gist are intended only to match web URLs -- http,
https, and naked domains like "example.com". For a pattern that attempts to
match all URLs, regardless of protocol, see: https://gist.github.com/gruber/249502
# Single-line version:
(?i)\b((?:https?:(?:/{1,3}|[a-z0-9%])|[a-z0-9.\-]+[.](?:com|net|org|edu|gov|mil|aero|asia|biz|cat|coop|info|int|jobs|mobi|museum|name|post|pro|tel|travel|xxx|ac|ad|ae|af|ag|ai|al|am|an|ao|aq|ar|as|at|au|aw|ax|az|ba|bb|bd|be|bf|bg|bh|bi|bj|bm|bn|bo|br|bs|bt|bv|bw|by|bz|ca|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co|cr|cs|cu|cv|cx|cy|cz|dd|de|dj|dk|dm|do|dz|ec|ee|eg|eh|er|es|et|eu|fi|fj|fk|fm|fo|fr|ga|gb|gd|ge|gf|gg|gh|gi|gl|gm|gn|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|hu|id|ie|il|im|in|io|iq|ir|is|it|je|jm|jo|jp|ke|kg|kh|ki|km|kn|kp|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|lu|lv|ly|ma|mc|md|me|mg|mh|mk|ml|mm|mn|mo|mp|mq|mr|ms|mt|mu|mv|mw|mx|my|mz|na|nc|ne|nf|ng|ni|nl|no|np|nr|nu|nz|om|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|ps|pt|pw|py|qa|re|ro|rs|ru|rw|sa|sb|sc|sd|se|sg|sh|si|s
@steipete
steipete / Macros.h
Last active January 6, 2024 07:24
Declare on your main init that all other init methods should call. It's a nice additional semantic warning. Works with Xcode 5.1 and above. Not tested with earlier variants, but should just be ignored. A reference to this macro shortly appeared in https://developer.apple.com/library/ios/releasenotes/ObjectiveC/ModernizationObjC/AdoptingModernObj…
#ifndef NS_DESIGNATED_INITIALIZER
#if __has_attribute(objc_designated_initializer)
#define NS_DESIGNATED_INITIALIZER __attribute((objc_designated_initializer))
#else
#define NS_DESIGNATED_INITIALIZER
#endif
#endif
@nicklockwood
nicklockwood / Hacking UIView Animation Blocks.md
Last active August 24, 2024 17:08
This article was originally written for objc.io issue 12, but didn't make the cut. It was intended to be read in the context of the other articles, so if you aren't familiar with concepts such as CALayer property animations and the role of actionForKey:, read the articles in that issue first.

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.

@jspahrsummers
jspahrsummers / GHRunLoopWatchdog.h
Created January 28, 2015 20:50
A class for logging excessive blocking on the main thread
/// Observes a run loop to detect any stalling or blocking that occurs.
///
/// This class is thread-safe.
@interface GHRunLoopWatchdog : NSObject
/// Initializes the receiver to watch the specified run loop, using a default
/// stalling threshold.
- (id)initWithRunLoop:(CFRunLoopRef)runLoop;
/// Initializes the receiver to detect when the specified run loop blocks for
@liscio
liscio / retinaify.sh
Created March 12, 2015 18:33
Make Preview open your @2x .png files as if they are retina images
#!/bin/sh
# First, set the width/height DPI on the file
sips -s dpiWidth 144 -s dpiHeight 144 "$1"
# Fake that it is a screen capture (wat?)
xattr -wx com.apple.metadata:kMDItemIsScreenCapture "62 70 6C 69 73 74 30 30 09 08 00 00 00 00 00 00 01 01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 09" "$1"
xattr -wx com.apple.metadata:kMDItemScreenCaptureType "62 70 6C 69 73 74 30 30 59 73 65 6C 65 63 74 69 6F 6E 08 00 00 00 00 00 00 01 01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 12" "$1"
xattr -wx com.apple.FinderInfo "00 00 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00" "$1"
@tehnoir
tehnoir / getudid.sh
Last active April 13, 2025 23:35
getudid
#!/bin/bash
function getUDID {
udid=($(system_profiler SPUSBDataType | grep -A 11 -w "iPad\|iPhone\|iPod\|AppleTV" | grep "Serial Number" | awk '{ print $3 }'))
if [ -z $udid ]; then
echo "No device detected. Please ensure an iOS device is plugged in."
exit 1
else
for id in "${udid[@]}"; do
if [ ${#id} -eq 24 ]; then
@mackuba
mackuba / wwdc15.md
Last active October 20, 2025 02:33
New stuff from WWDC 2015

Here's my own list of the interesting stuff announced during this year's WWDC, collected from the keynotes, various Apple docs, blog posts and tweets.

If you're planning to watch the videos, I really recommend this Mac app that helps you download and watch them: https://github.com/insidegui/WWDC.

OS X El Capitan

http://www.apple.com/osx/elcapitan-preview/

  • split view - two apps side by side on full screen