Home > Articles > Programming > C#

Sharing Rich Content in Windows 8 Apps

  • Print
  • + Share This
In this excerpt from Building Windows 8 Apps with C# and XAML, Jeremy Likness discusses Windows 8's standard API for sharing different types of data that may range from lightweight text to bitmap images and even file system objects.
From the book

Sharing content is now more popular than ever in today’s Internet-connected social media landscape. In previous versions of Windows, the primary way to share data between applications was by using the Windows Clipboard. If you wanted to build an application that could post content to the Internet, you had to build the process yourself by creating a user interface for sharing content and building the right code to interact with the various APIs exposed by different social media providers. Windows 8 changed the game by providing a standard API for sharing different types of data that may range from lightweight text to bitmap images and even file system objects.

The Share contract enables applications to share data in a standard way without having to know the details of what other applications are installed on the system or how they might handle shared data. Your application can act as a Share Source by providing content the user may want to share. It may also act as a Share Target that consumes content. Share interactions are facilitated through the DataTransferManager WinRT component that exists in the Windows.ApplicationModel.DataTransfer namespace. Full documentation for this namespace is available online at http://msdn.microsoft.com/en-us/library/windows/apps/windows.applicationmodel.datatransfer.aspx.

Sourcing Content for Sharing

The Wintellog3 application acts as a Share Source and can share details about blogs, posts, and images. Before you can successfully share, you will need appropriate applications installed that can receive the content. The ImageHelper2 application from Chapter 3, Extensible Application Markup Language (XAML) can receive images; the Mail client can receive links and text. I recommend you download, build, and deploy the Windows 8 Sample SDK application called “Sharing content target app sample” available online at http://code.msdn.microsoft.com/windowsapps/Sharing-Content-Target-App-e2689782/.

This application is specifically designed to receive all shared content types and is a great way to see how the process works. When the user chooses the Share charm, the DataRequested event is fired on the DataTransferManager component. The App class provides a method to register for this event:

public void RegisterForShare()
    var dataManager = DataTransferManager.GetForCurrentView();
    dataManager.DataRequested += DataManager_DataRequested;

The event is fired with a reference to the DataTransferManger and a parameter of type DataRequestedEventArgs. The parameter exposes a Request property of type DataRequest that in turn exposes a DataPackage object. This object is used to wrap any data you wish to share with other applications. Table 1 lists the types of data you can associate with the package.

Table 1: Data Types Supported by the DataPackage Class




A bitmap image


A custom data format, stored as JSON based on a schema defined at http://schema.org/ or a custom schema that is published and available for other applications to consume


Hypertext Markup Language content


Rich Text Format content

Storage Items

A list of type IStorageItem used for sharing files between applications


Plain text content


Uniform Resource Identifier

The data package also provides support for asynchronous requests by setting a data provider. The provider indicates the type of information to provide along with a callback that is invoked when the target application is ready for the data. This approach is used when the data you have to share requires significant processing time to package and deliver.

Along with the actual data content, you may also provide a thumbnail image that represents the data, a title, and a description. To actually implement the sharing, a property is exposed on the main App class to allow each individual page to supply a handler for sharing so that the proper context can be provided:

public Action<DataTransferManager, DataRequestedEventArgs> 
    Share { get; set; }

Pages that don’t provide any sharing functionally will set this to null when they are navigated to like the main GroupedItemsPage:

protected override void LoadState(Object navigationParameter, 
    Dictionary<String, Object> pageState)
    App.Instance.Share = null;
    DefaultViewModel["Groups"] = App.Instance.DataSource.GroupList;
    groupGridView.ItemsSource = 

The handler itself checks to see if a callback is registered, like this:

void DataManager_DataRequested(DataTransferManager sender, 
    DataRequestedEventArgs args)
    if (Share != null)
        Share(sender, args);

If no data is supplied, a message will be provided to the user indicating there is nothing to share. You can provide additional information if necessary to indicate why the share operation failed. The following code is added after the check to see if a callback exists:

        "Please choose a blog or item to enable sharing.");

The result of a share attempt is shown in Figure 1.

Figure 1 A failed share attempt with a custom message.

The pages that allow sharing register a method to handle the callback:

App.Instance.Share = Share;

If the user navigates to a blog entry, the share operation will provide the URL for the blog. First, a “reality check” ensures a current blog exists:

var group = DefaultViewModel["Group"] as BlogGroup;         
if (group == null)

Next, a title and description are supplied along with the URL:

dataRequestedEventArgs.Request.Data.Properties.Title = group.Title;
dataRequestedEventArgs.Request.Data.Properties.Description = 
    "Wintellog RSS feed.";

The ItemDetailPage contains more complex logic for sharing. If the user simply invokes the Share charm without selecting any text, the application will provide a link to the blog post along with the entire contents:


If an image exists for the blog post, the image itself is packaged as a bitmap:

if (item.DefaultImageUri != null)

The information for the blog post is also packaged using the custom data format.

Custom Data

Custom data enables you to package data based on a well-known schema like one provided at http://schema.org/ or your own. A schema is provided for blog posts at http://schema.org/BlogPosting, so any application that recognizes that schema can parse the information that is shared.

Custom data is typically stored in a JSON format. Due to limitations in the built-in DataContractJsonSerializer class (it does not provide a standardized format and requires attributes to successfully serialize an instance), I chose to use the popular open source Json.NET serializer by James Newton-King. You can read about it at http://james.newtonking.com/projects/json-net.aspx.

The library is packaged using NuGet (http://nuget.org), so installing it is as simple as opening the package manager (Tools[ra]Library Package Manager[ra]Package Manager Console) and typing the following (note the package name is case sensitive):

install-package Newtonsoft.Json

This automatically pulls down all necessary files and inserts a reference into the current project. This has already been done for you in the sample application. With the Json.NET library, I can create an anonymous type to hold the blog information and serialize it to JSON with a single line of code, as shown in Listing 1.

Listing 1: Serializing a Dynamic Type with Json.NET

private static async Task<string> CustomData(BlogItem item)
    var schema = new
            type = "http://shema.org/BlogPosting",
            properties = new
                    description = string.Format(
                    "Blog post from {0}.", 
                    image = item.DefaultImageUri,
                    name = item.Title,
                    url = item.PageUri,
                    audience = "Windows 8 Developers",
                    datePublished = item.PostDate,
                    headline = item.Title,
                    articleBody = item.Description
    return await JsonConvert.SerializeObjectAsync(schema);

To package the custom data, the SetData method is called and passed the schema and the JSON content:

var data = await CustomData(item);
    "http://schema.org/BlogPosting", data);

There are hundreds of existing schemas available for sharing rich data and content between applications. If you want to provide your own schema, you simply need to provide a unique URL that describes the schema format and then package the data using that schema. Any application that is aware of your schema can process the data by checking the schema type and handling the resulting data. You will learn how to receive and process shared data later in this chapter.

Text Selection

What if the user only desires to share a small excerpt from the blog post? Text selection is built into the existing text-based XAML controls. The content of the blog posts are hosted in a RichTextBlock control. The control exposes a SelectionChanged event:

<RichTextBlock x:Name="richTextBlock" Width="560" 
    Style="{StaticResource ItemRichTextStyle}"

Whenever this event fires, the selected text is saved to a local variable:

private void RichTextBlock_SelectionChanged_1(object sender, 
    RoutedEventArgs e)
    var richTextControl = sender as RichTextBlock;
    _selection = richTextControl != null ? 
        richTextControl.SelectedText : string.Empty;

When the Share charm is invoked and a selection exists, it is provided like this:

dataRequestedEventArgs.Request.Data.Properties.Title = 
    string.Format("Excerpt from {0}", item.Title);
dataRequestedEventArgs.Request.Data.Properties.Description =
    string.Format("An excerpt from the {0} blog at {1}.", 
    item.Group.Title, item.PageUri);
    string.Format("{0}\r\n\r\n{1}", _selection, item.Group.RssUri));

Figure 2 shows the result of selecting a single sentence from a blog post then sharing it to the sample application referred to earlier in this chapter.

Figure 2 Sharing a simple excerpt

The decision to include the URL of the original post in the text instead of the package itself is an example of targeting the share for a specific purpose. It is the excerpt that is the focus when text is selected, not the source page. Sharing the source URL in the main package may cause other applications to pull the full page and lose the intent of simply sharing an excerpt. Therefore, the only content provided is in the text portion of the data package.

  • + Share This
  • 🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020