Tricertops

Values with priority in KeepLayout

Every numeric value used in KeepLayout need to have associated priority. This pair is then passed to the underlying NSLayoutConstraint of Auto Layout.

Before

The KeepValue type was an ordinary struct with .value and .priority, so it had to be created using one of the provided functions:

view.keepWidth.equal = KeepRequired(100); // value 100, priority 1000

Tricertops

@interface List : NSObject

@property (copy) NSArray *items;
@property (readonly) NSMutableArray *mutableItems;

@end


@implementation List

Tricertops

View → Design → Model

iOS applications are usually built with MVC (Model – View – Controller) architecture, which introduces very important concept of separating actual data (Model Layer) and their presentation (View Layer), while the application logic (Controller Layer) stands between them.

View ← Controller → Model

With MVC you typically write most of the code in UIViewController, which usually represents the Controller Layer. View Layer can be easily done in Interface Builder and Model Layer usually doesn’t need a lot of code. The UIViewControleler then holds strong references to both View and Model objects and is responsible for setting them up, handling actions and listening to events.

The problem is, that this middle layer tends to hold too much code and this situation is then jokingly called Massive View Controller. When a single class sets up views, formats data values, handles user input and actions, listens for a bunch of notif

Tricertops

import UIKit
import CoreText

extension UIFont {
    
    typealias Feature = (type: Int, selector: Int)
    struct Features {
        static var ProportionalNumbers: Feature = (kNumberSpacingType, kProportionalNumbersSelector)
        static var AlternatePunctuation: Feature = (kCharacterAlternativesType, 1) // Magic!
    }

Tricertops

@import Foundation;


@interface NSObject (ThreadSafeProxy)

- (instancetype)threadSafe;

@end

Tricertops

- (NSString *)clockForHour:(NSUInteger)hour {
    NSArray *clocks = @[ @"🕛", @"🕐", @"🕑", @"🕒", @"🕓", @"🕔",
                         @"🕕", @"🕖", @"🕗", @"🕘", @"🕙", @"🕚" ];
    NSUInteger index = hour % clocks.count;
    return [clocks objectAtIndex:index];
}

Tricertops

// This triggers correct KVO insertion notification:
[parent.mutableChildren addObject:@"Child"];

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// Network request failed, due to lost internet conenction...

OCAErrorRecoveryAttempter *recoveryAttempter = [[OCAErrorRecoveryAttempter alloc] init];

// Recovery suggestion will be be presented together with error message.
recoveryAttempter.recoverySuggestion = @"Make sure you are connected to the Internet and try again.";

// Creates reactive recovery option and chains an invocation to [self start].
[[recoveryAttempter addRecoveryOptionWithTitle:@"Retry"] invoke:OCAInvocation(self, start)];

Tricertops

<?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">
<dict>
	<key>DVTConsoleDebuggerInputTextColor</key>
	<string>0.715709 0.129913 0.185409 1</string>
	<key>DVTConsoleDebuggerInputTextFont</key>
	<string>Menlo-Regular - 13.0</string>
	<key>DVTConsoleDebuggerOutputTextColor</key>
	<string>1 1 1 1</string>

Tricertops

+ (void)enumerateAdoptedProtocolsOfProtocol:(Protocol *)protocol usingBlock:(void(^)(Protocol *adoptedProtocol))block {
    unsigned int adoptedCount = 0;
    Protocol * __unsafe_unretained *adoptedProtocolList = protocol_copyProtocolList(protocol, &adoptedCount);
    if (adoptedProtocolList) {
        for (NSUInteger index = 0; index < adoptedCount; index++) {
            Protocol *adoptedProtocol = adoptedProtocolList[index];
            
            block(adoptedProtocol);
        }
        free(adoptedProtocolList);