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@intergalacticspacehighway
intergalacticspacehighway / PinchToZoom.tsx
Last active April 23, 2024 20:16
Pinch to zoom reanimated + gesture handler
import React, { useMemo, useState } from "react";
import { LayoutChangeEvent, StyleSheet } from "react-native";
import {
PinchGestureHandler,
PinchGestureHandlerGestureEvent,
} from "react-native-gesture-handler";
import Animated, {
useAnimatedGestureHandler,
useAnimatedStyle,
useSharedValue,
import type { LoaderFunction, ActionFunction } from "remix";
import { useLoaderData, useFetcher } from "remix";
import invariant from "tiny-invariant";
import cuid from "cuid";
import React from "react";
import type { Task, User } from "@prisma/client";
import { requireAuthSession } from "~/util/magic-auth";
import { ensureUserAccount } from "~/util/account";
import { placeCaretAtEnd } from "~/components/range";
import { getBacklog } from "~/models/backlog";
@kitze
kitze / store.js
Created January 24, 2018 13:14
simplified redux
import produce from 'immer';
import {createStore} from 'redux';
const handleActions = (actionsMap, defaultState) => (
state = defaultState,
{type, payload}
) =>
produce(state, draft => {
const action = actionsMap[type];
action && action(draft, payload);
@knowbody
knowbody / RNfontWeights.js
Created July 14, 2016 13:42
React Native Font Weight Cheatsheet iOS
{ fontWeight: '100' }, // Thin
{ fontWeight: '200' }, // Ultra Light
{ fontWeight: '300' }, // Light
{ fontWeight: '400' }, // Regular
{ fontWeight: '500' }, // Medium
{ fontWeight: '600' }, // Semibold
{ fontWeight: '700' }, // Bold
{ fontWeight: '800' }, // Heavy
{ fontWeight: '900' }, // Black
@irace
irace / CenteringView.swift
Last active November 29, 2017 19:31
I’m building a complex new app entirely with programmatic Auto Layout. It only supports iOS 9 so that means `UIStackView` and `NSLayoutAnchor` exclusively. These two classes have been very handy thus far, in the spirit of composition over inheritance.
final class CenteringView: UIView {
// MARK: - Initialization
init(contentView: UIView) {
super.init(frame: .zero)
addSubview(contentView)
contentView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activateConstraints([
@lunelson
lunelson / gsap-properties-cheat-sheet.md
Last active January 28, 2024 22:07
Greensock Properties Cheat Sheet

Greensock CSS properties Cheat Sheet

I wrote this as a reference for myself because some of the property names are non-obvious, and there are a number of relevant special properties, and there is no central concise listing of them all in GSAP Docs, other than (in longer form) on the CSSPlugin page.

Standard CSS properties

...are all supported, with hyphenated-names becoming camelCaseNames. Non-animatable properties are also supported but they will be set at the beginning of the tween.

Special mentions:

@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
@nicklockwood
nicklockwood / Hacking UIView Animation Blocks.md
Last active June 18, 2024 15:35
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.

@jstn
jstn / RandomNumbers.swift
Last active May 5, 2023 03:26
generate random numbers for 64-bit types while mitigating modulo bias
/*
`arc4random_uniform` is very useful but limited to `UInt32`.
This defines a generic version of `arc4random` for any type
expressible by an integer literal, and extends some numeric
types with a `random` method that mitigates for modulo bias
in the same manner as `arc4random`.
`lower` is inclusive and `upper` is exclusive, thus:
@steipete
steipete / UIKitLegacyDetector.m
Last active March 12, 2024 13:57
A simple way to detect at runtime if we're running in UIKit legacy mode or the new "flat" variant. Written for our PDF iOS SDK (http://pspdfkit.com), where the precompiled binary needs to detect at runtime in what variant it's running. Want more stuff like that? Follow me on Twitter: http://twitter.com/steipete
// Taken from http://PSPDFKit.com. This snippet is under public domain.
#define UIKitVersionNumber_iOS_7_0 0xB57
BOOL PSPDFIsUIKitFlatMode(void) {
static BOOL isUIKitFlatMode = NO;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
// We get the modern UIKit if system is running >= iOS 7 and we were linked with >= SDK 7.
if (kCFCoreFoundationVersionNumber >= kCFCoreFoundationVersionNumber_iOS_7_0) {
isUIKitFlatMode = (NSVersionOfLinkTimeLibrary("UIKit") >> 16) >= UIKitVersionNumber_iOS_7_0;
}