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@mayoff
mayoff / makeAnimatedGif.m
Created February 16, 2013 23:00
Example of creating an animated GIF on iOS, with no 3rd-party code required. This should also be easy to port to OS X.
#import <UIKit/UIKit.h>
#import <ImageIO/ImageIO.h>
#import <MobileCoreServices/MobileCoreServices.h>
static UIImage *frameImage(CGSize size, CGFloat radians) {
UIGraphicsBeginImageContextWithOptions(size, YES, 1); {
[[UIColor whiteColor] setFill];
UIRectFill(CGRectInfinite);
CGContextRef gc = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(gc, size.width / 2, size.height / 2);
@mmick66
mmick66 / UICollectionViewFlowLayoutCenterItem.m
Last active August 2, 2022 10:06
UICollectionViewFlowLayout with arbitrary sized Paging
#import "UICollectionViewFlowLayoutCenterItem.h"
@implementation UICollectionViewFlowLayoutCenterItem
- (CGPoint)targetContentOffsetForProposedContentOffset:(CGPoint)proposedContentOffset withScrollingVelocity:(CGPoint)velocity
{
CGSize collectionViewSize = self.collectionView.bounds.size;
CGFloat proposedContentOffsetCenterX = proposedContentOffset.x + self.collectionView.bounds.size.width * 0.5f;
CGRect proposedRect = self.collectionView.bounds;
@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.

@mnbayan
mnbayan / MKMapViewExtension.swift
Created February 23, 2015 02:33
MKMapView extension to center map to coordinates with defined zoom level using Swift language
//
// MKMapViewExtension.swift
// AutocompleteTextfieldSwift
//
// Created by Mylene Bayan on 2/22/15.
// Copyright (c) 2015 MaiLin. All rights reserved.
//
import Foundation
import MapKit
@hfossli
hfossli / Display.swift
Last active July 13, 2020 16:22
Display mode
import UIKit
public enum DisplayType {
case unknown
case iphone4
case iphone5
case iphone6
case iphone6plus
static let iphone7 = iphone6
static let iphone7plus = iphone6plus
@objc protocol Refreshable
{
/// The refresh control
var refreshControl: UIRefreshControl? { get set }
/// The table view
var tableView: UITableView! { get set }
/// the function to call when the user pulls down to refresh
@objc func handleRefresh(_ sender: Any);
@NikhilManapure
NikhilManapure / Gif.swift
Last active October 29, 2023 07:31
Create Gif from array of UIImages in Swift 3
import Foundation
import UIKit
import ImageIO
import MobileCoreServices
extension UIImage {
static func animatedGif(from images: [UIImage]) {
let fileProperties: CFDictionary = [kCGImagePropertyGIFDictionary as String: [kCGImagePropertyGIFLoopCount as String: 0]] as CFDictionary
let frameProperties: CFDictionary = [kCGImagePropertyGIFDictionary as String: [(kCGImagePropertyGIFDelayTime as String): 1.0]] as CFDictionary
@shaps80
shaps80 / AVPlayer+Scrubbing.swift
Last active June 12, 2024 00:09
Enables smooth frame-by-frame scrubbing (in both directions) – similar to Apple's applications.
public enum Direction {
case forward
case backward
}
internal var player: AVPlayer?
private var isSeekInProgress = false
private var chaseTime = kCMTimeZero
private var preferredFrameRate: Float = 23.98
@vhart
vhart / Swift4-ReadWriteDelete.swift
Last active November 8, 2022 16:15
File Handling from an Xcode Playground
//: Playground - noun: a place where people can play
import UIKit
import PlaygroundSupport
func setUpDemo() {
let testContents = """
This is a test
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