joyrexus

collapsible markdown?

CLICK ME

yes, even hidden code blocks!

print("hello world!")

nicklockwood

Suppose we want to add support for a new iOS 8 API in our framework that replaces an older iOS 7 API. There are a few problems we might face:

1. The new API will crash if we call it on iOS 7
2. The new API won't compile if we build it using the iOS 7 SDK
3. The old API will raise a deprecation warning if built with a deployment target of iOS 8 and up

These three problems require three different technical solutions:

1. We can avoid calling the new API on an old OS version by using runtime detection (e.g. respondsToSelector:)
2. We can avoid compiling new APIs on old SDKs using the __IPHONE_OS_VERSION_MAX_ALLOWED macro

steipete

static Boolean PSPDFCaseInsensitiveEqualCallback(const void *a, const void *b) {
    id objA = (__bridge id)a, objB = (__bridge id)b;
    Boolean ret = FALSE;
    if ([objA isKindOfClass:NSString.class] && [objB isKindOfClass:NSString.class]) {
        ret = ([objA compare:objB options:NSCaseInsensitiveSearch|NSLiteralSearch] == NSOrderedSame);
    }else {
        ret = [objA isEqual:objB];
    }
    return ret;
}

floriankugler

NSURLConnection                                                                                             | NSURLSession
------------------------------------------------------------------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------
NSURLConnectionDelegate            connectionShouldUseCredentialStorage:                                    |
------------------------------------------------------------------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------
NSURLConnectionDelegate            connection:willSendRequestForAuthenticationChallenge:                    | NSURLSessionDelegate            URLSession:didReceiveChallenge:completionHandler:
                                                                                                            | N

steipete

// 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>

steipete

// Defines a yet undocumented method to add a warning if super isn't called.
#ifndef NS_REQUIRES_SUPER
#if __has_attribute(objc_requires_super)
#define NS_REQUIRES_SUPER __attribute((objc_requires_super))
#else
#define NS_REQUIRES_SUPER
#endif
#endif

@interface UIViewController (SubclassingWarnings)

tomohisa

// add child view
    UIViewController* controller = [self.storyboard instantiateViewControllerWithIdentifier:@"test"];
    [self addChildViewController:controller];
    controller.view.frame = CGRectMake(0, 44, 320, 320);
    [self.view addSubview:controller.view];
    [controller didMoveToParentViewController:self];

// remove child view
    UIViewController *vc = [self.childViewControllers lastObject];
    [vc.view removeFromSuperview];

jxson

Synopsis

At the top of the file there should be a short introduction and/ or overview that explains what the project is. This description should match descriptions added for package managers (Gemspec, package.json, etc.)

Code Example

Show what the library does as concisely as possible, developers should be able to figure out how your project solves their problem by looking at the code example. Make sure the API you are showing off is obvious, and that your code is short and concise.

Motivation