View source for DCR Italy Video iOS SDK

{{Breadcrumb|}} {{Breadcrumb|Digital}} {{Breadcrumb|International DCR}}  {{CurrentBreadcrumb}}
[[Category:Digital]]

== Overview ==
The Nielsen SDK is one of multiple framework SDKs that Nielsen provides to enable measuring linear (live) and on-demand TV viewing using TVs, mobile devices, etc.
The App SDK is the framework for mobile application developers to integrate Nielsen Measurement into their media player applications. It supports a variety of Nielsen Measurement Products like Digital in TV Ratings, Digital Content Ratings ([[DCR & DTVR]]), and [[Digital Ad Ratings]] (DAR). Nielsen SDKs are also equipped to measure static content and can track key life cycle events of an application like:
*Application launch events and how long app was running
*Time of viewing a page / sub section in the application.

== Prerequisites ==
Before you start the integration, you will need:
{| class="wikitable"
|-
! style="width: 15%;" | Item
! Description
! Source
|-
 || '''App ID (appid)''' || Unique ID assigned to the player/site and configured by product. || Provided by Nielsen
|-
 || '''Nielsen SDK''' || Includes SDK frameworks and '''sample implementation'''; ''See [[iOS SDK Release Notes]]'' || [[Special:Downloads|Download]]
|-
 || '''sfcode''' || Unique identifier for the environment that the SDK should point to || Provided by Nielsen
|}

If need App ID(s) or our SDKs, feel free to reach out to us and we will be happy to help you get started.
Refer to [[Digital Measurement Onboarding]] guide for information on how to get a Nielsen App SDK and appid.

=== Notes for WebView Contents ===
<code>Please note that if within your APP user can surf '''static contents''' recalled from your website the [[DCR_Italy_Static_Browser_SDK|browser static SDK]] have to inhibit from this pages.</code>
__TOC__

==  Implementation ==
This guide covers implementation steps for iOS using Xcode utilizing the Standard Nielsen SDK for DCR.

<code>If you are building an app for the 'kids category' please review the [[DCR_Italy_Video_iOS_SDK#Special_Note_Regarding_Apps_in_the_Kids_Category|Opt Out Requirement.]]</code>

=== How to obtain the NielsenAppApi.Framework ===
The Nielsen AppSDK can either be downloaded directly or can be integrated directly within an application through the use of CocoaPods. We recommend using the CocoaPods-based integration whenever possible to ensure you maintain the most recent changes and enhancements to the Nielsen libraries.
* [[Digital_Measurement_iOS_Artifactory_Guide|Select to obtain CocoaPods implementation guide]]
* [[Special:Downloads|Select to Download Directly]]
* [[DCR_Video_iOS_SDK_xcframework|Using the XCFramework bundle]]

== Special Notes regarding iOS14 ==
=== Permission to Track === 

Apple recently released a new policy on consent requirements, that require the user's permission, to track them using their device's advertising identifier (IDFA).  To request the user's permission, use the AppTrackingTransparency framework. 

For more information, see:
* [https://developer.apple.com/documentation/apptrackingtransparency App Tracking Transparency]
* [https://developer.apple.com/design/human-interface-guidelines/ios/app-architecture/requesting-permission/ Human Interface Guidelines]
* [https://developer.apple.com/documentation/adsupport AdSupport Framework]

More detailed information on how the Nielsen SDK versions work with the AppTrackingTransparency framework is located on our [[ DCR Video iOS14 Migration|DCR Video iOS14 Migration]] page.

== Setting up your  Development Environment  ==
Prior to SDK Version 6.2.0.0 the  IOS framework has been distributed as a static library packaged into framework bundle format. Apple recommends to use dynamic framework, it has some benefits over static libraries like less executable file size of an app, faster startup time and native support in xCode IDE. Nielsen AppSDK has been transformed into dynamic framework in this release ([[iOS_Static_Framework_Setup|static framework]] is still available).

If migrating from the static library to this new dynamic framework, once implemented, unless your specific application requires, you can remove the following Frameworks that were once required:<code> [AdSupport, JavascriptCore, SystemConfiguration, Security, AVFoundation, libc++] </code>
<br>

The '''Dynamic framework''' is created as a fat framework. It means that it contains slices required for devices (armv7, arm64) as well as slices required for simulators (i386, x86_64). Simulator slices are needed to let clients build and debug their app on the simulators, but they should be removed before sending the app to the AppStore. The example of the shell script that should be added as a Run Script phase in the application can be [[DCR_Video_iOS_SDK#Removing_Simulators_.28Dynamic_Framework_Only.29|found below]].

'''[[DCR_Video_iOS_SDK_xcframework|XCFramework]]''' is solution for the problems described above Apple recommends to use XCFrameworks. In XCFramework, we no longer build a single framework with multiple architectures. Instead, we build one small framework for each combination of architecture and target and store it in its own folder. The top-level XCFramework folder have folders like ios-arm64, ios-arm64-simulator, etc. Each of these folders is its own framework, complete with headers, modules, and binary.

=== Configuring Xcode Development Environment ===
Starting with SDK version 6.0.0.0, the Nielsen App SDK is compatible with Apple iOS versions 8.0 and above.  In addition, when using the dynamic framework,  all the required frameworks are linked automatically as the are needed.  More details can be found here: https://stackoverflow.com/questions/24902787/dont-we-need-to-link-framework-to-xcode-project-anymore

<blockquote>'''Note''': All communications between the SDK and the Census (Collection Facility) use HTTPS.</blockquote>

=== Special Note for Static Framework ===
Starting from 8.2.0.0 release framework is build from the mixed (swift + objc) source codse.
If [[iOS_Static_Framework_Setup|static (xc)framework is integrated additional settings]] should be applied to fix build or runtime issues.

=== Download Framework ===
The first step is to download and copy the [[Special:Downloads|NielsenAppApi.framework]] bundle to the app project directory. (''Not required if using CocaPods'')

=== Add Framework ===
In the General tab for app configuration add NielsenAppApi.framework in the list of Embedded Binaries.  (''Not required if using CocaPods'')

=== Add Path ===
Add path to the NielsenAppApi.framework in the Framework Search Paths build setting.  (''Not required if using CocaPods'')

=== Import Framework ===
Add NielsenAppApi.framework module in the source file of your app:

==== Using Swift ====
Add the following:
<syntaxhighlight lang="swift">
import NielsenAppApi
</syntaxhighlight>

==== Using Objective-C ====
<syntaxhighlight lang ="objective-c">
@import NielsenAppApi;
</syntaxhighlight>

==== xCode 12 building errors ====
Developers who uses "fat" framework in their apps started reporting the following error that they get building the app in xCode 12.3+:
<blockquote>Building for iOS Simulator, but the linked and embedded framework 'MyFramework.framework' was built for iOS + iOS Simulator.</blockquote>
The binary framework contains different code for the same architecture in multiple places, and Xcode doesn’t know how to handle it. There is workaround that people recommend to use in such cases:
* https://stackoverflow.com/questions/63267897/building-for-ios-simulator-but-the-linked-framework-framework-was-built
* https://stackoverflow.com/questions/63932158/xcode12-issus-ld-building-for-ios-simulator-but-linking-in-object-file-built

==== IPA processing failure ====
<code>Assertion failed: Expected 4 archs in otool output:</code>

The error above is due to the "fat" (simulator+device) framework which will not appear if you have not enabled Bitcode.  To build your app with full Bitcode support, it is recommended that you use a [[DCR_Video_iOS_SDK_xcframework|XCFramework]] to avoid the 4 archs in otool output message.

== SDK Initialization ==
The latest version of the Nielsen App SDK allows instantiating multiple instances of the SDK object, which can be used simultaneously without any issue. The sharedInstance API that creates a singleton object was deprecated prior to version 5.1.1. [[Dual_Instances_of_SDK|(Click here for an example of multiple instances)]]

The following table contains the list of arguments that can be passed via the AppInfo JSON schema.
*The appid is provided by the Nielsen Technical Account Manager (TAM). The appid is a GUID data type and is specific to the application.
{| class="wikitable"
|-
! Parameter / Argument !! Description !! Source !! Required? !! Example
|-
| appid || Unique Nielsen ID for the application. The ID is a GUID data type. If you did not receive your App ID, let us know and we will provide you. || Nielsen-specified || Yes || PXXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
|-
| appname || Name of the application
|| Client-defined || Yes || "Nielsen Sample App"
|-
| appversion || Current version of the app used
|| Client-defined || Yes || "1.0.2"
|-
| sfcode || Nielsen collection facility to which the SDK should connect.
Italian Clients:
*"it"
|| Nielsen-specified || Yes || "it"
|-
| nol_devDebug || Enables Nielsen console logging. Only required for testing
|| Nielsen-specified || Yes for Debugging / Testing App || "DEBUG"
|}

== Debug flag for development environment ==
Player application developers / integrators can use Debug flag to check whether an App SDK API call made is successful. To activate the Debug flag,
Pass the argument <code>@"nol_devDebug":@"DEBUG"</code>, in the JSON string . The permitted values are:

* '''INFO''': Displays the API calls and the input data from the application (validate player name, app ID, etc.). It can be used as certification Aid.
* '''WARN''': Indicates potential integration / configuration errors or SDK issues.
* '''ERROR''': Indicates important integration errors or non-recoverable SDK issues.
* '''DEBUG''': Debug logs, used by the developers to debug more complex issues.

Once the flag is active, it logs each API call made and the data passed. The log created by this flag is minimal.
<blockquote>'''Note''': Activate the Debug flag in a Test environment.</blockquote>

=== Sample SDK Initialization Code ===

==== App tracking transparency framework ====

To display the App Tracking Transparency authorization request for accessing the IDFA, update your <code>info.plist</code> to add the <code>NSUserTrackingUsageDescription</code> key with a custom message describing your usage. Below is an example description text:
<code><key>NSUserTrackingUsageDescription</key></code>
<code><string>This identifier will be used to deliver personalized ads to you.</string></code>

The system automatically generates the prompt’s title, which includes the name of your app, then the usage description appears as part of the App Tracking

To present the authorization request, call requestTrackingAuthorizationWithCompletionHandler.

<blockquote>Please NOTE: It is important to initialize the NielsenSDK after the ATTrackingManager has Authorized usage.  When the SDK initializes, it checks the status of the ATTrackingManager.</blockquote>

You can find an example in the file [[Special:Downloads|Global iOS SDK Download]] from the '''SDK Downloads''' section, folder name NielsenSampleVideoPlayer.

====Swift 4.0 Example:====
<code>NielsenInit.swift</code>
<syntaxhighlight lang="swift">
import Foundation
import NielsenAppApi

class NielsenInit : NSObject {
    class func createNielsenApi(delegate: NielsenAppApiDelegate) -> NielsenAppApi?{
        
        let appInformation:[String: String] = [
            "appid": "PDA7D5EE6-B1B8-4123-9277-2A788XXXXXXX",
            "appversion": "1.0.2",
            "appname": "Nielsen Sample App",
            "sfcode": "it",
            "nol_devDebug": "DEBUG"
        ]       
        return NielsenAppApi(appInfo:appInformation, delegate:delegate)
    }
}
</syntaxhighlight>

===Sample code using AVPlayer===
<code>ViewController.swift</code>

<syntaxhighlight lang="swift">
class ViewController: UIViewController, NielsenAppApiDelegate, AVPictureInPictureControllerDelegate, CLLocationManagerDelegate  {
    
    let avPlayerViewController = AVPlayerViewController()
    var avPlayer:AVPlayer?
    var nielsenAppApi: NielsenAppApi!

  override func viewDidLoad() {
        super.viewDidLoad()

self.nielsenAppApi = NielsenInit.createNielsenAppApi(delegate: self)
NSLog("Nielsen SDK initialized")

            }
  }
</syntaxhighlight>

===Objective C ==== 
Initialize the Nielsen App object within the viewDidLoad view controller delegate method using initWithAppInfo:delegate:
<blockquote>If App SDK is initialized using init or new methods, it will ignore the API calls resulting in no measurement. The SDK will not return any errors.</blockquote>
<syntaxhighlight lang="objective-c">    
#import "NlsAppApiFactory.h"
#import <NielsenAppApi/NielsenAppApi.h>

@implementation NlsAppApiFactory

+ (NielsenAppApi *)createNielsenAppApiWithDelegate:(id<NielsenAppApiDelegate>)delegate;
{
    
    
    NSDictionary *appInformation = @{ 
                                     @"appid": "PDA7D5EE6-B1B8-4123-9277-2A788XXXXXXX",
                                     @"appversion": "1.0.2",
                                     @"appname": "Nielsen Sample App",
                                     @"sfcode": "it",
                                     @"nol_devDebug": @"DEBUG"
                                    };
    
    return [[NielsenAppApi alloc] initWithAppInfo:appInformation delegate:delegate];
}

@end
</syntaxhighlight>


The following would be the <code>NlsAppApiFactory.h</code> file:
<syntaxhighlight lang="objective-c">
#import <Foundation/Foundation.h>

@class NielsenAppApi;
@protocol NielsenAppApiDelegate;

@interface NlsAppApiFactory : NSObject 

+ (NielsenAppAPI *) createNielsenAppApiWithDelegate:(id<NielsenAppApiDelegate>)delegate;

@end
</syntaxhighlight>

=== Sample Code: ===
<syntaxhighlight lang="objective-c">
@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
        
    //Getting the instance of Nielsen SDK
    nielsenApi = [NlsAppApiFactory createNielsenAppApiWithDelegate:nil];
}}
</syntaxhighlight>

<!--
== Initializing the Nielsen AppSDK to measure the Viewability ==
The integrator to support the viewability metrics in the application has to provide a tag value of the player view to let Nielsen AppSDK know that there is a player that needs to be tracked. It’s called the ‘containerId’ and it should be passed in application info dictionary as string while initializing the Nielsen AppSDK.

=== Android ===
{| class="wikitable"
|-
! #	!! Parameter Name	!! Description !! Supported Values !! Example
|-
| 1	|| containerId ||View ID of the UI element used as player view in application. getId() method of View class can be used to get this value.	||A positive integer used to identify the view. || 2131558561
|}

=== iOS ===
{| class="wikitable"
|-
! #	!! Parameter Name	!! Description !! Supported Values !! Example
|-
| 1	|| containerId ||The tag of the UIView that represents the Player View	||The string value representing the NSInteger value with maximum value of NSIntegerMax that is related on 32- or 64-bit applications. || "100" <br> "2131558561"
|}

For iOS it is required to link additional frameworks that are needed for viewability engine:<br>
<code>JavaScriptCore.framework</code> <br>
<code>WebKit.framework</code>

The Nielsen AppSDK uses a tracking WebView (TWV) approach.  For more information on Viewability, please refer to [https://engineeringportal.nielsen.com/docs/Implementing_Viewability_with_AppSDK Implementing Viewability with AppSDK.]
-->

== APP SDK Error & Event Codes ==
To view the Error and Event codes for iOS, please review the [[APP SDK Event Codes|App SDK Event Code]] Reference page.

== Configure Metadata ==
=== Handling JSON Metadata ===
All the SDK methods handles only two types of objects: NSString, NSDictionary. The parameters passed must be either a JSON formatted string or a NSDictionary object. The JSON passed in the SDK must be well-formed.
* NSDictionary object
** If an object of unexpected type is passed to the method, the error message will be logged.
** If string has invalid JSON format, the error message will be logged.
* JSON value must be string value.
** This includes boolean and numeric values. For example, a value of true should be represented with "true", number value 123 should be "123".
** All the Nielsen Key names (e.g. appid, program) are case-sensitive. Use the correct variable name as specified in the documentation.
* JSON string can be prepared using either raw NSString or serialized NSDictionary.
{{ExampleCode|
|Swift = 
<syntaxhighlight lang="swift">

let channelInfo = [
            "channelName": "My Channel Name 1",
];
        
let contentMetadata = [
            "type": "content",
            "assetid": "88675545",
            "title": "Program S3, EP1",
            "isfullepisode":"y",
            "adloadtype":"2",
            "program":"Program Name",
            "length":"3600", 
            "airdate":"20171020 10:05:00"
];
</syntaxhighlight>     
|Objective C = <syntaxhighlight lang="objective-c">
NSDictionary  *channelInfo = @
{
  @"channelName":@"My Channel Name 1",
}

NSDictionary * contentMetadata = @ {
    @ "type": @ "content",
    @ "assetid": @ "88675545",
    @ "title": @ "Program S3, EP1",
    @ "isfullepisode": @ "y",  
    @ "program": @ "Program Name",
    @ "length": @ "3600",
    @ "airdate": @ "20200321 10:05:00",
    @ "adloadtype": @ "2"
}
</syntaxhighlight>
}}
<!--
=== Configure metadata === 
channelName should remain constant throughout the completion of an episode or live stream.
{| class="wikitable"
|-
! Key !! Description !!	Values	 !! Required
|-
| channelName	|| ChannelInfo refers to the Channel name. This can be a free-form value
value such as a friendly name for the content being played. the SDK<br/>
will pass the application name automatically.
|| custom	|| No
|-
|}
-->

=== Configure metadata ===
Configure metadata should remain constant throughout the completion of an episode or live stream
{| class="wikitable"
|-
! Keys	!! Description	!! Values	!! Required
|-
| channelName 	|| Any string representing the channel/stream || custom || Yes
|}


=== Content Metadata ===
Content metadata should remain constant throughout the entirety of an episode/clip including when ads play.
{| class="wikitable"
|-
! Keys	!! Description	!! Values	!! Required
|-
| type 	|| type of asset || <code>'content'</code> || Yes
|-
| assetid || unique ID assigned to asset (32 Character limit) || custom (no [[Special Characters|Special Characters]]) || Yes
|-
| program || name of program (100 character limit) || custom || Yes
|-
| title || name of program (100 character limit) || custom || Yes
|-
| length || length of content in seconds || <code>seconds</code> (0 for live stream) || Yes
|-
| airdate || the airdate in the linear TV || YYYYMMDD HH24:MI:SS || Yes
|-
| isfullepisode || full episode flag || <code>'y'</code>- full episode, <code>'n'</code>- non full episode || Yes
|-
| adloadtype || type of ad load:
*<code>'1'</code> Linear – matches TV ad load
*<code>'2'</code> Dynamic – Dynamic Ad Insertion (DAI)
|| <code>'2'</code> - DCR measures content with dynamic ads 
|| Yes

|}

=== Ad Metadata ===
The Ad Metadata (if applicable) should be passed for each individual ad.
{| class="wikitable"
|-
! Keys	!! Description	!! Values	!! Required
|-
| type 	|| type of Ad	||  <code>'preroll'</code>,  <code>'midroll'</code>,  <code>'postroll'</code> || Yes
|-
| assetid ||	unique ID assigned to Ad	|| custom (no [[Special Characters|Special Characters]]) || Yes
|}

=== Example Ad Object ===
<syntaxhighlight lang="javascript">
// create Ad object
"ad": {
  "type": "preroll",
  "assetid": "AD-ID123"
}
</syntaxhighlight>

== Configure API Calls ==
<!--[[File:appsdkTimeline-DCR.png|icon|link=]]-->
=== Sample API Sequence ===
A Sample API sequence could follow this flow:
{| class="wikitable"
|-
! Type !! Sample code !! Description
|-
|On App Start||<syntaxhighlight lang=Swift>
NielsenInit.createMainBrandApi(delegate: self)
self.data = loadStaticMetadata()
self.nielsenMeter .loadMetadata(self.data)</syntaxhighlight> || // Pass Static Metadata here if applicable
|-
| rowspan="2" | Start of stream || <code>nielsenMeter.play()</code> || // Call at start of each new stream
|-
| <code>nielsenMeter.loadMetadata(contentMetadata)</code> || // MetadataObject contains the JSON metadata<br> for the content being played
|-
| Content || <code>nielsenMeter.playheadPosition(pos);</code> || // playheadPosition is position of the playhead <br>while the content is being played
|-
| End of Stream || <code>nielsenMeter.end()</code> || // Content playback is completed.
|}

=== SDK Events ===
{| class="wikitable"
|-
! Event !!	Parameter	!! Description
|-
| 'play'	|| 	|| Call at start of each new stream
|-
| 'loadMetadata'	|| content/ad metadata object	|| Needs to be called at the beginning of each asset
|-
| 'playheadPosition'	|| playhead position as integer<br/>
VOD: current position in seconds <br/>
Live: current UNIX timestamp (seconds since Jan-1-1970 UTC) <br/>
Note: 'PlayheadPosition' has to be called every second
||
Pass playhead position every second during playback
|-
| 'stop' ||	playhead position	|| Call during any interruption to content or Ad playback and at the end of each Ad.
|-
| 'end'	|| playhead position in seconds	|| Call when the current video asset completes playback and pass the playhead position. <br/>
Example: At the end of the content stream, if the user switches to another piece of content, when the videoplayer is reloaded or closed.
|}
<blockquote>Note: For livestream, send the UNIX timestamp, for VOD send the time in seconds as integer. The final playhead position must be sent for the current asset being played before calling <code>'''stop'''</code>, <code>'''end'''</code> or<code> '''loadmetadata'''</code>,.</blockquote>

=== Life cycle of SDK instance ===
Life cycle of SDK instance includes four general states:
# '''Initial state''' – The SDK is not initialized and hence, not ready to process playing information. Once the SDK is moved out of this state, it needs instantiation of the new SDK instance in order to get the instance in the '''Idle state'''.
# '''Idle state''' – The SDK is initialized and is ready to process playing information. Once Initialized, the SDK instance is not processing any data, but is listening for an event to occur.
# '''Processing state''' – The SDK instance is processing playing information. The <code>'''play'''</code> and <code>'''loadMetadata''' </code> calls move the SDK instance into this state. In this state, the SDK instance will be able to process the following calls.
## <code>'''playheadPosition'''</code> – Call this API every one second when playhead position is active.  If a LIVE event, use the current UNIX timestamp (seconds since Jan-1-1970 UTC).
## <code>'''stop'''</code> – Call this API when the content or Ad playback is interrupted and at the end of each Ad. 
## <code>'''end'''</code> – Call when content completes. When called, the SDK instance exits from Processing state.
# '''Disabled state''' – The SDK instance is disabled and is not processing playing information. 
## <code>'''appDisableApi'''</code> is set to <code>true</code>

<blockquote>'''Note:''' For API Version 5.1 and above, App SDK will fire data pings and continue measurement even after the user has opted out from Nielsen measurement on a device. The data ping will be marked as opted-out ping.

'''Note''': In case of any interruptions during playback due to alarm, calendar, call, flight mode, Wi-Fi toggle, channel change, etc., call [[stop]] to stop the measurement.
* As soon as the playback resumes, call <code>'''loadMetadata''' </code> and   <code>'''playheadPosition'''</code> </blockquote>

=== API Call Sequence ===
==== Use Case 1: Content has no Advertisements ====
Call [[play()]] at start of stream

Call [[loadMetadata()]] with JSON metadata for content as below.
<syntaxhighlight lang="json">{
  "type": "content",
  "assetid": "88675545",
  "title": "Program S3, EP1",
  "isfullepisode":"y",
  "adloadtype":"2",
  "program":"Program Name",
  "length":"3600", 
  "airdate":"20171020 10:05:00"   
}</syntaxhighlight>
Call [[playheadPosition|playheadPosition()]] every one second until a pause / stop.
Use the sample API sequence below as a reference to identify the specific events that need to be called during content playback without ads.
{| class="wikitable"
|-
! Type !! Sample code !! Description
|-
| rowspan="2" | Start of stream || <code>mAppSdk.play(); </code> || // Call at start of each new stream
|-
| <code>mAppSdk.loadMetadata(contentMetaDataObject);</code> || // contentMetadataObject contains the JSON metadata for the content being played
|-
| Content || <code>mAppSdk.setPlayheadPosition(playheadPosition);</code> || // position is position of the playhead while the content is being played
|-
| Interruption || <code>mAppSdk.stop();</code> || // call stop when content playback is interrupted
|-
| rowspan="2" | Resume Content || <code>mAppSdk.loadMetadata(contentMetaDataObject);</code>  || // Call loadMetadata and pass content metadata object when content resumes
|- 
|<code>mAppSdk.setPlayheadPosition(playheadPosition);</code> || // continue pasing playhead position every second starting from position where content is resumed
|- 
| End of Stream || <code>mAppSdk.end();</code> || // Content playback is completed.
|}

==== Use Case 2: Content has Advertisements ====

<blockquote>Note:
*For Audiweb there is no need to tag ads in video stream ... please see 1st example about how to use the SDK without ads.</blockquote>

Call [[play()]] at start of stream

Call [[loadMetadata()]] with JSON metadata for ad as below.
<syntaxhighlight lang="json">{
   "type": "preroll",
   "assetid": "ad123"
}</syntaxhighlight>
<blockquote>Note: In case the individual ad details are not available, send ad pod (presence) details through the [[loadMetadata]] and playhead position through [[playheadPosition]].</blockquote>

Call [[playheadPosition|playheadPosition()]] every one second until a pause / stop / another [[loadMetadata()]] is called. Playhead should be passed for the entire duration of ad pod, if the ad pod details are passed as part of [[loadMetadata()]].

The sample API sequence can be used as a reference to identify the specific events that need to be called during content and ad playback.
{| class="wikitable"
|-
! Type !! Sample code !! Description
|-
| rowspan="2" | Start of stream || <code>mAppSdk.play(); </code> || // stream starts
|-
| <code>mAppSdk.loadMetadata(contentMetaDataObject);</code> || // contentMetadataObject contains the JSON metadata for the content being played
|-
| rowspan="3" | Preroll || <code>mAppSdk.loadMetadata(prerollMetadataObject);</code> || // prerollMetadataObject contains the JSON metadata for the preroll ad
|-
| <code>mAppSdk.playheadPosition(playheadPosition);</code> || // position is position of the playhead while the preroll ad is being played
|-
| <code>mAppSdk.stop();</code> || // Call stop after preroll occurs
|-
| rowspan="2" | Content || <code>mAppSdk.loadMetadata(contentMetaDataObject);</code> || // contentMetadataObject contains the JSON metadata for the content being played
|-
| <code>mAppSdk.playheadPosition(playheadPosition);</code> || // position is position of the playhead while the content is being played
|-
| rowspan="3" | Midroll || <code>mAppSdk.loadMetadata(midrollMetaDataObject);</code> || // midrollMetadataObject contains the JSON metadata for the midroll ad
|-
| <code>mAppSdk.playheadPosition(playheadPosition);</code> || // position is position of the playhead while the midroll ad is being played
|-
| <code>mAppSdk.stop();</code> || // Call stop after midroll occurs
|-
| rowspan="2" | Content Resumes || <code>mAppSdk.loadMetadata(contentMetaDataObject);</code> || // contentMetadataObject contains the JSON metadata for the content being played
|-
| <code>mAppSdk.playheadPosition(playheadPosition);</code> || // position is position of the playhead while the content is being played
|-
| End of Stream || <code>mAppSdk.end();</code> || // Call end() at the end of content
|-
| rowspan="3" | Postroll || <code>mAppSdk.loadMetadata(postrollMetaDataObject);</code> || // postrollMetadataObject contains the JSON metadata for the postroll ad
|-
| <code>mAppSdk.playheadPosition(playheadPosition);</code> || // position is position of the playhead while the postroll ad is being played
|-
| <code>mAppSdk.stop();</code> || // Call stop after postroll occurs
|}

<blockquote>Note: Each Ad playhead should begin from 0 at ad start.  When content has resumed following an ad break, playhead position must continue from where previous content segment was left off.</blockquote>

== Sequence of Calls ==
=== play ===
Call <code>play</code> at the start of each new stream. If changing videos or watching a new video, call <code>play()</code> each time. 
{{ExampleCode|
|Objective C = <syntaxhighlight lang="objective-c">   [nielsenAppApi play:()];</syntaxhighlight>
|Swift = <syntaxhighlight lang="swift">nielsenAppApi?.play();</syntaxhighlight>
}}

=== loadMetadata ===
{{ExampleCode|
|Objective C = <syntaxhighlight lang="objective-c">[nielsenApi loadMetadata:(contentMetadata)];</syntaxhighlight>
|Swift = <syntaxhighlight lang="swift">self.nielsenAppApi?.loadMetadata(contentMetadata)</syntaxhighlight>
}}

=== playheadPosition ===
{{ExampleCode|
|Objective C = <syntaxhighlight lang="objective-c">

-(void) setPlayHeadPosition {
    
    //Setting play head position
    CMTime timeInterval = CMTimeMakeWithSeconds(1, 1);
    [player addPeriodicTimeObserverForInterval:(timeInterval) queue:dispatch_get_main_queue() usingBlock:^(CMTime time){
        NSTimeInterval seconds = CMTimeGetSeconds(time);
        NSInteger intSec = seconds;
        
        //Sending data dictionary to SDK with updated playHead position.
        [nielsenApi playheadPosition:(intSec)];
    }];
}
</syntaxhighlight>

|Swift = <syntaxhighlight lang="swift">
        //Monitor the Playhead position of the AVPlayer
        let timeInterval: CMTime = CMTimeMakeWithSeconds(1.0,10)
        self.avPlayerViewController.player?.addPeriodicTimeObserver(forInterval: timeInterval, queue: DispatchQueue.main) {(elapsedTime: CMTime) -> Void in
            if self.avPlayerViewController.player!.currentItem?.status == .readyToPlay {
                let time : Float64 = self.avPlayerViewController.player!.currentTime().seconds;
                let pos = Int64(time);
                NSLog("New Elapse Time = \(time)");
                self.nielsenAppApi?.playheadPosition(pos);
            }
        }
    }
</syntaxhighlight>
}}

=== stop ===
{{ExampleCode|
|Objective C = <syntaxhighlight lang="objective-c">[nielsenApi stop];</syntaxhighlight>
|Swift = <syntaxhighlight lang="swift">nielsenApi.stop()</syntaxhighlight>
}}

=== end ===
When content stop is initiated and content cannot be resumed from the same position (it can only be restarted from the beginning of stream).
{{ExampleCode|
|Objective C = <syntaxhighlight lang="objective-c">[nielsenApi end];</syntaxhighlight>
|Swift = <syntaxhighlight lang="swift">nielsenApi.end()</syntaxhighlight>
}}

== Handling Foreground and Background states ==
For iOS, background/foreground detection is handled by the app lifecylce APIs which are provided by [https://developer.apple.com/library/content/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/TheAppLifeCycle/TheAppLifeCycle.html Apple:]

Foreground/Background state measurement is a requirement of Nielsen AppSDK implementation which is especially crucial for static measurement.

== Interruptions during playback ==
As part of integrating Nielsen App SDK with the player application, the Audio / Video app developer needs to handle the following possible interruption scenarios:
* Pause / Play
* Network Loss (Wi-Fi / Airplane / Cellular)
* Call Interrupt (SIM or Third party Skype / Hangout call)
* Alarm Interrupt
* Content Buffering
* Device Lock / Unlock 
* App going in the Background/Foreground 
* Channel / Station Change Scenario
* Unplugging of headphone
In case of encountering one of the above interruptions, the player application needs to
* Call [[stop]] immediately (except when content is buffering) and withhold sending playhead position.
* Start sending API calls – <code>'loadMetadata'</code> and <code>'playheadPosition'</code> for the new viewing session, once the playback resumes.
Please see the [https://engineeringportal.nielsen.com/docs/Digital_Measurement_Interruption_Scenarios Interruption Scenarios Page] for more details

== Privacy and Opt-Out ==
There are two primary methods for implementing user Opt-out preferences:

*[[DCR_Italy_Video_iOS_SDK#OS-level_Opt-out|OS-level Opt-out]] - managed by AppTracking or Limit Ad Tracking setting on device (preferred approach).
*[[DCR_Italy_Video_iOS_SDK#User_Choice|User Choice]] - Direct call to SDK. Can be used without the Ad Framework

=== Special Note Regarding Apps in the Kids Category ===
If you are building an app that will be listed in the Kids Category:

Ensure that you are using the [https://nielsendownloads-green.digitalengsdk.com/digital/Nielsen-iOS-App-SDK-GlobalNoId_latest.zip NoID version:] of the Nielsen SDK Framework. Also, you can use the [[Digital_Measurement_iOS_Artifactory_Guide|Artifactory method.]]
Immediately following the initialization of the Nielsen SDK ensure you call the userOptOut API with Opt out selection:
<syntaxhighlight lang="swift">NielsenAppApi?.userOptOut("nielsenappsdk://1"); // User opt-outv</syntaxhighlight>

=== OS-level Opt-out ===
''OS-level Opt-out'' method available on Nielsen iOS

The Nielsen SDK automatically leverages the iOS's '''Limit Ad Tracking''' or '''AppTracking''' setting.

*If the User's device is running < iOS 13.x, the Nielsen SDK will check the status of '''Limit Ad Tracking'''.
*iOS14 modifies the way Apple manages the collection of a User's Opt-In status through '''AppTracking'''. Starting with Version 8.x+, the Nielsen App SDK will check the iOS version during initialization. If the device is running iOS12 or iOS13, the Limit Ad Tracking setting is requested. If iOS14.x +, then AppTracking is utilized.

==== Get the latest Nielsen opt-out URL ====

*Get the current Nielsen opt-out URL via [[optOutURL|optOutURL]]
*Display a WebView element whose loadUrl is set to the value obtained from [[optOutURL|optOutURL]]

==== Webview Example ====
The below code is an example of displaying the Nielsen Privacy page to the user.
<blockquote>Note: Apple released a policy update stating that the App Store will no longer accept updates for apps using the deprecated UIWebView (no specific date has been confirmed). Since then, we’ve recommended that you adopt WKWebView instead of UIWebView and WebView.
</blockquote>
<syntaxhighlight lang="swift">
import UIKit
import WebKit
import NielsenAppApi

class OptOutVC: UIViewController, NielsenAppApiDelegate, WKNavigationDelegate {
    var webView: WKWebView!
    var nielsenApi: NielsenAppApi!
    
    override func loadView() {
        webView = WKWebView()
        webView.navigationDelegate = self
        view = webView  }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.view.backgroundColor = UIColor(patternImage: UIImage(named: "new_ios_bg.png")!) 
        self.nielsenApi = NielsenInit.createNielsenApi(delegate: self)  //create an instance 
        
        if let appApi = self.nielsenApi {
            //Getting the optPut URL from SDK
            if let url = URL(string: appApi.optOutURL) { //query the nielsensdk for the current privacy page
                webView.load(URLRequest(url: url))
                webView.allowsBackForwardNavigationGestures = true
            }}}}
</syntaxhighlight>

=== User Choice ===
The User Choice method can be used without the Ad Framework, or in situations where the publisher does not wish to use the [https://developer.apple.com/documentation/apptrackingtransparency App Tracking Transparency Framework.]

==== The User Choice opt-out method works as follows: ====

*Get the Nielsen opt-out URL via [[optOutURL|optOutURL]]
*Display a WebView element whose loadUrl is set to the value obtained from [[optOutURL|optOutURL]]
*Detect if the WebView URL changes to a special URL that indicates Opt-in, or Opt-out and close the WebView
**Opt-out if the WebView URL = <code>nielsenappsdk://1</code>
**Opt-in if the WebView URL = <code>nielsenappsdk://0</code>
*Pass the detected URL to the [[userOptOut|userOptOut]] function
Example:
<syntaxhighlight lang="swift">NielsenAppApi?.userOptOut("nielsenappsdk://1"); // User opt-out </syntaxhighlight>

==== Opt-out example code ====
<blockquote>Note: Apple released a policy update stating that the App Store will no longer accept updates for apps using the deprecated UIWebView (no specific date has been confirmed). Since then, we’ve recommended that you adopt WKWebView instead of UIWebView and WebView.
</blockquote>

===== Objective-C =====

<syntaxhighlight lang="objective-c">
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)
navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {

    NSURLRequest *request = [navigationAction request];
    NSString *url = [[request URL]absoluteString];
    
    if([url isEqualToString:self.NIELSEN_URL_OPT_OUT] || [url isEqualToString:self.NIELSEN_URL_OPT_IN]){
        [self.nielsenApi userOptOut:url];
        decisionHandler(WKNavigationActionPolicyAllow);
    }else{
        decisionHandler(WKNavigationActionPolicyCancel);
    }        
}
</syntaxhighlight>

===== Swift =====
<syntaxhighlight lang="swift">
var webView: WKWebView!
var NIELSEN_URL_OPT_OUT : String = "nielsenappsdk://1"
var NIELSEN_URL_OPT_IN : String = "nielsenappsdk://0"

func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, 
decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {

       let urlStr = navigationAction.request.url?.absoluteString

        if(urlStr == NIELSEN_URL_OPT_OUT || urlStr == NIELSEN_URL_OPT_IN){
            let appApi = self.nielsenApi
            appApi?.userOptOut(urlStr)
            decisionHandler(.allow)

        }else{
           decisionHandler(.cancel)
        }
    }
</syntaxhighlight>

=== Retrieve current Opt-Out preference ===
Whether the user is opted out via OS-level Opt-out or via User Choice Opt-out, the current Opt-Out status as detected by the SDK is available via the [[optOutStatus|optOutStatus]] property in the Nielsen SDK API

==== Required Privacy Links ====
Users must either have access to the "About Nielsen Measurement" page, or have similar text available within the native app. Include "About Nielsen Measurement" and "Your Choices" link in the Privacy Policy / EULA or as a button near the link to the app's Privacy Policy.

In addition, the following text must be included in your app store description.

"Si prega di notare che questa app include il software di misurazione proprietario di Nielsen che contribuisce alla ricerca di mercato. Per ulteriori informazioni, si prega di consultare il seguente link [https://www.nielsen.com/it/it/legal/privacy-statement/digital-measurement/ https://www.nielsen.com/it/it/legal/privacy-statement/digital-measurement/]"

== Going Live ==
Following Nielsen testing, you will need to:

# '''Disable Debug Logging''': Disable logging by deleting <code>{nol_devDebug: 'DEBUG'}</code> from initialization call.
# '''Notify Nielsen''': Once you are ready to go live, let us know so we can enable you for reporting. We will not be able to collect or report data prior to receiving notification from you.

== Removing Simulators (Dynamic Framework Only)==

Simulator slices are needed to let clients build and debug their app on the simulators, but they should be removed before sending the app to the AppStore.  Here is an example Shell script that could be added as a Run Script phase in the application.


<syntaxhighlight lang='bash'>

APP_PATH="${TARGET_BUILD_DIR}/${WRAPPER_NAME}"

# This script loops through the frameworks embedded in the application and
# removes unused architectures.
find "$APP_PATH" -name '*.framework' -type d | while read -r FRAMEWORK
do
FRAMEWORK_EXECUTABLE_NAME=$(defaults read "$FRAMEWORK/Info.plist" CFBundleExecutable)
FRAMEWORK_EXECUTABLE_PATH="$FRAMEWORK/$FRAMEWORK_EXECUTABLE_NAME"
echo "Executable is $FRAMEWORK_EXECUTABLE_PATH"

EXTRACTED_ARCHS=()

for ARCH in $ARCHS
do
echo "Extracting $ARCH from $FRAMEWORK_EXECUTABLE_NAME"
lipo -extract "$ARCH" "$FRAMEWORK_EXECUTABLE_PATH" -o "$FRAMEWORK_EXECUTABLE_PATH-$ARCH"
EXTRACTED_ARCHS+=("$FRAMEWORK_EXECUTABLE_PATH-$ARCH")
done

echo "Merging extracted architectures: ${ARCHS}"
lipo -o "$FRAMEWORK_EXECUTABLE_PATH-merged" -create "${EXTRACTED_ARCHS[@]}"
rm "${EXTRACTED_ARCHS[@]}"

echo "Replacing original executable with thinned version"
rm "$FRAMEWORK_EXECUTABLE_PATH"
mv "$FRAMEWORK_EXECUTABLE_PATH-merged" "$FRAMEWORK_EXECUTABLE_PATH"

done
</syntaxhighlight>

== Sample Applications ==
You can find some examples in the file [[Special:Downloads|Global iOS SDK Download]] from the '''SDK Downloads''' section