iOS 9 Adaptation Tutorial Series

This article is a contribution article, author: ChenYilong (https://github.com/ChenYilong/iOS9AdaptationTips)

Demo1_iOS9 network adaptation_Switch to more secure HTTPS

iOS9 changes all http requests to https: Network requests sent by iOS9 system will all use TLS 1.2 SSL. The purpose of using TLS 1.2 protocol is to enforce enhanced data access security, and related network requests under the system Foundation framework will no longer use unsafe network protocols such as Http by default, but use TLS 1.2 by default. Therefore, the server needs to be updated to parse the relevant data. If not updated, it can be declared in Info.plist to fall back to unsafe network requests.

Before the discussion, as usual, let's talk about the issues that iOS programmers are most concerned about:

What does it have to do with me? Do you need me to work overtime?!

First, let's take a look at the industry's comments on Apple's approach:

This was a discussion on a social app. It seems that there are both complaints and affirmations in the industry.

Conclusion:

It has a lot to do with you, work overtime, young man!

Let's get back to the topic [serious face], let's formally discuss WHAT, WHY, HOW:

1. WHAT (What is SSL/TLS? How does it relate to HTTP and HTTPS)

2. WHY (Can't the old HTTP be used? Why use SSL/TLS? Are you so idle?! Is Apple being anti-human again?)

3. HOW (How to adapt? --- Just a quick question: How long will it take to work overtime?)

WHAT (What is SSL/TLS? How does it relate to HTTP and HTTPS)

As usual, let me start with the conclusion:

 HTTP+SSL/TLS+TCP = HTTPS

TLS is the new nickname for SSL. For example:

"TLS1.0" is to "SSL3.1" as "2015 AD" is to "104 of the Republic of China", or "one kilogram" is to "one kilogram", or "half a catty" is to "eight taels": different names, but the same meaning.

The subsequent iterations of SSL 3.0 were renamed TLS 1.0.

That is:

 TLS 1.0 = SSL 3.1  

So they are the same thing, and we often simply see the term "SSL/TLS".

The most commonly used ones are the following:

• SSL 2.0

• SSL 3.0

• TLS 1.0 (SSL 3.1)

• TLS 1.1 (SSL 3.1)

• TLS 1.2 (SSL 3.1)

So why is the title "Use HTTPS" and doesn't mention anything about SSL and TLS? To understand this, look at the next formula:

 HTTP+SSL/TLS+TCP = HTTPS

To use an analogy: if the original HTTP is a plastic water pipe that is easily punctured, then the newly designed HTTPS is like wrapping a metal water pipe around the original plastic water pipe. First, the original plastic water pipe still works; second, after being reinforced with metal, it is not easy to be punctured.

Currently, the most widely used is TLS 1.0, followed by SSL 3.0. However, mainstream browsers have already implemented support for TLS 1.2.

Apple allows you to use SSL/TLS protocol for HTTP, which means you can switch from HTTP to HTTPS

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WHY (Can't the old HTTP be used? Why use SSL/TLS? Are you so idle?! Is Apple being anti-human again?)

HTTP communication without SSL/TLS is unencrypted communication!

All information is transmitted in plain text, which brings three major risks:

1. Eavesdropping risk: A third party may be able to learn the content of the communication.

2. Tampering risk: A third party can modify the content of the communication.

3. Pretending risk: A third party can pretend to be someone else and participate in the communication.

The SSL/TLS protocol is designed to address these three risks, hoping to achieve:

1. All information is transmitted in encrypted form and cannot be eavesdropped by third parties.

2. It has a verification mechanism. Once it is tampered with, the communicating parties will find it immediately.

3. Equipped with identity certificate to prevent identity impersonation.

HOW (How to adapt? --- Just a quick question: How long will it take to work overtime?)

As stated at the beginning of the article:

TLS 1.2 protocol enforces enhanced data access security. Network requests under the Foundation framework will no longer use unsafe network protocols such as Http by default, but will use TLS 1.2 by default. The server therefore needs to be updated to parse relevant data. If not updated, you can declare in Info.plist to fall back to unsafe network requests.

Solution 1: Immediately upgrade the company's server to use TLS 1.2

Solution 2: Although Apple does not recommend it, you can declare in Info.plist that falling back to insecure network requests will still allow the App to access the specified http, or even any http.

See the gif for specific steps and Demo1 for example

As Apple's official documentation says:

The XML source code in the Info.plist configuration is as follows:

The above is a more rigorous approach, which specifies which specific HTTPs can be accessed. Of course, there are also violent approaches: completely fall back to insecure HTTP network requests, and can make any HTTP request, for example, if you are developing a browser app, or you want to be lazy, or the backend wants to be lazy, or the company does not upgrade the server for you...

Disclaimer: Currently, Apple's official documentation does not mention how to configure in Info.plist. I will pay close attention to the official documentation and update this article if it is mentioned.

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Demo2_iOS9 new features_More flexible background positioning

Demo: GitHub address

[There is both bad news and good news about iOS9's positioning] Bad news: If you don't support iOS9, you can't secretly position in the background (without the blue bar, see the picture)! Good news: This scenario will be allowed: multiple location managers in the same app: some can only position in the foreground, and others can position in the background, and you can turn on or off the background positioning of a specific location manager at any time.

If you do not request background location permission, you can still locate in the background, but there will be a blue bar:

How to secretly locate in the background: Request background location permission:

   // 1. Instantiate the positioning manager  
 _locationManager = [[CLLocationManager alloc] init];
 // 2. Set up the proxy  
 _locationManager.delegate = self;
 // 3. Positioning accuracy  
 [_locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
 // 4. Request user permissions: divided into: ?Only enable positioning in the foreground?Allow positioning in the background,  
 //Note: It is recommended to request only one of ? and ?. If both permissions are required, only request ?.  
 //??Such an order will lead to a bug: after the first launch of the program, the system will only request the permission of ?, and will not request the permission of ?. It will only request ? when the application is launched next time.  
 if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8 ) {
 //[_locationManager requestWhenInUseAuthorization]; //? Only enable positioning in the foreground  
 [_locationManager requestAlwaysAuthorization]; //? Location is also possible in the background  
 }
 // 5. New features of iOS 9: This scenario will be allowed: multiple location managers in the same app: some can only be located in the foreground, while others can be located in the background (and their background positioning can be disabled at any time).  
 if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 9 ) {
    _locationManager.allowsBackgroundLocationUpdates = YES;
 }
 // 6. Update user location  
 [_locationManager startUpdatingLocation];

But if you try this approach without configuring Info.plist, your app will 100% crash with the following error:

 *** Assertion failure in -[CLLocationManager setAllowsBackgroundLocationUpdates:],
 /BuildRoot/Library/Caches/com.apple.xbs/Sources/CoreLocationFramework_Sim/CoreLocation-1808.1.5/
 Framework/CoreLocation/CLLocationManager.m:593

To configure Info.plist as follows:

The corresponding Info.plist XML source code is:

Bitcode (Popular explanation: online version of Android ART mode)

In the future, Watch apps must include Bitcode. iOS does not require it, but Xcode7 will enable Bitcode by default.

How to adapt?

Method 1: Update the library to include Bitcode, otherwise the following warning will appear;

 ( null ): URGENT: all bitcode will be dropped because '/Users/myname/Library/
 Mobile Documents/com~apple~CloudDocs/foldername/appname/GoogleMobileAds.framework/
 GoogleMobileAds(GADSlot+AdEvents.o)' was built without bitcode.
 You must rebuild it with bitcode enabled (Xcode setting ENABLE_BITCODE),
 obtain an updated library from the vendor, or disable bitcode for   this target.
 Note: This will be an error in the future.

For more information, please visit Apple's official documentation on bitcode and WWDC 2015 Session 102: "Platforms State of the Union"

[[140110]]

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Enterprise-level distribution

Before iOS9, enterprise-level distribution was very convenient: click on the App and a “Trust button” will appear.

After iOS9, enterprise-level ipa packages will be treated the same as dmg installation packages on Mac: they cannot be installed by default, and the "Trust button" will no longer appear.

The user must make the settings shown in the gif (related Demo: https://github.com/ChenYilong/iOS9AdaptationTips/ )

URL scheme

In iOS 9, if you use URL scheme, you must whitelist the URL scheme you want to call externally in "Info.plist", otherwise it cannot be used. The key is called LSApplicationQueriesSchemes, and the key value is

 LSApplicationQueriesSchemes urlscheme urlscheme2 urlscheme3 urlscheme4

Recommend a blog: http://awkwardhare.com/post/121196006730/quick-take-on-ios-9-url-scheme-changes

The most critical parts are as follows:

 If you call the “canOpenURL” method on a URL that is not in your whitelist,
 it will return “NO”, even if there is an app installed that has registered to handle this scheme.
 A “This app is not allowed to query for scheme xxx” syslog entry will appear.
 If you call the “openURL” method on a URL that is not in your whitelist, it will fail silently.
 A “This app is not allowed to query for scheme xxx” syslog entry will appear.

For more information, please go to: WWDC 2015 Session 703: "Privacy and Your App" at around 30:18

iPad adapts Slide Over and Split View

[iPad adapts Slide Over and Split View] If you want to adapt to the multi-tasking feature, the only suggestion is to abandon pure code and use storyboard and xib instead. This is the case for all Apple WWDC demos:

1. Mysteries of Auto Layout, Part 1

2. What's New in Storyboards

3. Implementing UI Designs in Interface Builder

4. Getting Started with Multitasking on iPad in iOS 9

5. Optimizing Your App for Multitasking on iPad in iOS