leilee

+ (void)animateWithDuration:(NSTimeInterval)duration
             timingFunction:(CAMediaTimingFunction*)timingFunction
                 animations:(void (^)(void))animations
                 completion:(void (^)(BOOL finished))completion
{
    [CATransaction begin];
    [CATransaction setAnimationDuration:duration];
    [CATransaction setAnimationTimingFunction:timingFunction];

    [UIView animateWithDuration:duration animations:animations completion:completion];

leilee

class ClosureSleeve {
    let closure: () -> ()
    
    init(attachTo: AnyObject, closure: @escaping () -> ()) {
        self.closure = closure
        objc_setAssociatedObject(attachTo, "[\(arc4random())]", self, .OBJC_ASSOCIATION_RETAIN)
    }
    
    @objc func invoke() {
        closure()

leilee

extension Int {
    func times(_ closure: (Int) throws -> Void) rethrows {
        try (0...self).forEach {
            try closure($0)
        }
    }
    
    @discardableResult
    func times<T>(_ closure: (Int) throws -> T) rethrows -> [T] {
        var result: [T] = []

leilee

Just launch Wireshark from terminal:

sudo /Applications/Wireshark.app/Contents/MacOS/Wireshark

leilee

extension UIColor {
    
    class var random: UIColor {
        get {
            let hue : CGFloat = CGFloat(arc4random() % 256) / 256 // use 256 to get full range from 0.0 to 1.0
            let saturation : CGFloat = CGFloat(arc4random() % 128) / 256 + 0.5 // from 0.5 to 1.0 to stay away from white
            let brightness : CGFloat = CGFloat(arc4random() % 128) / 256 + 0.5 // from 0.5 to 1.0 to stay away from black
            
            return UIColor(hue: hue, saturation: saturation, brightness: brightness, alpha: 1)
        }

leilee

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        auto opMaker = ^NSOperation*(int idx) {
            return [NSBlockOperation blockOperationWithBlock:^{
                sleep(1);
                NSLog(@"opration %zd finished", idx);
            }];
        };

leilee

• Open Xcode -> Preferences -> Components.
• Open the Console App, clear the console.
• Go back to the Xcode preferences. Start the simulator download, then cancel it.
• Now in the Console, you will see something about the cancellation with the download URL.
• Copy the URL from the Console, download it.
• Copy this file to ~/Library/Caches/com.apple.dt.Xcode/Downloads.
  • If Downloads did not exist, create a new Downloads directory.
  • If Downloads exists, remove all *.dvtdownloadableindex files under it.
• Open Xcode -> Preferences -> Components, start the simulator download again, it should find the file you downloaded and install it.

leilee

+ (void)memoryCacheBenchmark
{
    NSMutableDictionary* dict = [NSMutableDictionary new];
    NSCache* cache = [NSCache new];
    int count = 10000, repeat = 100;

    NSMutableArray* keys = [NSMutableArray new];
    NSMutableArray* values = [NSMutableArray new];
    for (int i = 0; i < count; i++)
    {

leilee

- (void)showCamera
{
    auto showCamera = ^{
        if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
        {
            // TODO: alert
            return;
        }

        auto availableMediaTypes = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypeCamera];

leilee

#pragma once

#import <CoreGraphics/CoreGraphics.h>

#pragma mark - CGSize

CG_INLINE
CGSize operator*(const CGSize& lhs, CGFloat f)
{
    return (CGSize){lhs.width * f, lhs.height * f};