ns-CloudKit.xml

<Namespace Name="CloudKit">
  <Docs>
    <summary>The CloudKit namespace provides access to iCloud.</summary>
    <remarks>
      <para>The CloudKit namespace allows application developers to control the flow of data between their applications and iCloud. iCloud provides server-side data storage, both "public" that is shared between all instances of an application or specific applications and "private" that is unique to a single user. iCloud storage and transport is encrypted and synchronized between Apple devices. CloudKit does not provide client-side persistence or data caching -- CloudKit functionality is only available while the user has an active Internet connection.</para>
      <para>The highest-level class in the CloudKit is <see cref="T:CloudKit.CKContainer" />. A CloudKit Container (sometimes referred to in Apple documentation as a "Ubiquity container") is an information store identified with a particular name. Apple advises using a name of the form "iCloud.{reverse DNS}.{appName}", for instance, "iCloud.com.mycompany.MyApp". Developers must create and configure their containers using the iCloud Dashboard, available by way of the Apple developer portal.</para>
      <para>A single <see cref="T:CloudKit.CKContainer" /> may contain both public data, which is shared between all instances of the app (see <see cref="P:CloudKit.CKContainer.PublicCloudDatabase" />), and private data, which contains user-specific data (see <see cref="P:CloudKit.CKContainer.PrivateCloudDatabase" />). Within iCloud, public data is stored in the app's iCloud storage while private data is stored in the user's private iCloud storage. The public <see cref="T:CloudKit.CKDatabase" /> is available to all connected users of the app, whether or not they are logged in to iCloud. The private <see cref="T:CloudKit.CKDatabase" /> is only if the user is logged in to iCloud. Developers must write their code such that it reacts gracefully to changes in the user's login or connection status.</para>
      <para>These public and private <see cref="T:CloudKit.CKDatabase" /> objects store structured records. These are represented by <see cref="T:CloudKit.CKRecord" /> objects. In addition to field-like key-value data, these records may hold <see cref="T:CloudKit.CKAsset" /> large objects either directly (retrieved with the containing <see cref="T:CloudKit.CKRecord" />) or as references (allowing lazy retrieval of the large data).</para>
      <para>All <see cref="T:CloudKit.CKRecord" /> instances are stored within a <see cref="T:CloudKit.CKRecordZone" />. A <see cref="T:CloudKit.CKRecordZone" /> is something like a traditional database instance: it can contain multiple <see cref="T:CloudKit.CKRecord" /> stores that may refer to each other but not to stores in other <see cref="T:CloudKit.CKRecordZone" /> instances and <see cref="T:CloudKit.CKRecordZone" /> objects can be used to coordinate atomic operations across multiple <see cref="T:CloudKit.CKRecord" /> stores. The similarity to a database instance is not universal; for instance, a developer may use <format type="text/html"><a href="https://docs.microsoft.com/en-us/search/index?search=M:CKDatabase.FetchRecordAsync(CKRecordID)&amp;scope=Xamarin" title="M:CKDatabase.FetchRecordAsync(CKRecordID)">M:CKDatabase.FetchRecordAsync(CKRecordID)</a></format> to retrieve a <see cref="T:CloudKit.CKRecord" /> directly from the <see cref="T:CloudKit.CKDatabase" /> without referring to the zone. The default <see cref="T:CloudKit.CKRecordZone" /> is available via <format type="text/html"><a href="https://docs.microsoft.com/en-us/search/index?search=P:CloudKit.CKRecordZone.DefaultRecordZone()&amp;scope=Xamarin" title="P:CloudKit.CKRecordZone.DefaultRecordZone()">P:CloudKit.CKRecordZone.DefaultRecordZone()</a></format>. Developers may create additional zones using the CloudKit dashboard and use them to partition their data logically.</para>
      <para>CloudKit apps require a provisioning profile with the <c>com.apple.developer.icloud-services</c> entitlement and an app-specific Bundle Identifier (e.g., "com.mycompany.CloudKitApp"). Developers must create and configure such an provisioning profile.</para>
      <para>The following demonstrates some typical uses of CloudKit that work on single records:</para>
      <example>
        <code lang="csharp lang-csharp"><![CDATA[
//Create 
private async Task<CKRecord> StoreInCloudKit (string name, CLLocation loc, int stationId)
{
    string containerName = "iCloud.com.xamarin.CKWork";
    var container = CKContainer.FromIdentifier (containerName);
    CKDatabase publicDatabase = container.PublicCloudDatabase;
    var zoneId = CKRecordZone.DefaultRecordZone ().ZoneId;
    var recordType = "StationReferences";

    var record = new CKRecord (recordType);
    record ["Name"] = new NSString (name);
    record ["Position"] = loc;
    record ["StationID"] = new NSNumber (stationId);

    var storedRecord = await publicDatabase.SaveRecordAsync (record);
    return storedRecord;
}

//Retrieve (via ID)
private async Task<CKRecord> AccessCloudKit ()
{
    string containerName = "iCloud.com.xamarin.CKWork";
    var container = CKContainer.FromIdentifier (containerName);
    CKDatabase publicDatabase = container.PublicCloudDatabase;

    var recordNameIHappenToKnow = "7eaf0432-2fa4-475f-851a-c6a19b3f8587";
    var recordId = new CKRecordID (recordNameIHappenToKnow);
    var record = await publicDatabase.FetchRecordAsync (recordId);

    return record;
}

//Retrieve (query)
private async Task<CKRecord []> QueryCloudKit ()
{
    string containerName = "iCloud.com.xamarin.CKWork";
    var container = CKContainer.FromIdentifier (containerName);
    CKDatabase publicDatabase = container.PublicCloudDatabase;
   
    var zoneId = CKRecordZone.DefaultRecordZone ().ZoneId;
    Console.WriteLine ($"Default zone name = '{zoneId.ZoneName}' owner = '{zoneId.OwnerName}'");
    /*
    var zoneName = "_defaultZone";
    var ownerName = "__defaultOwner__";
    var zoneId0 = new CKRecordZoneID (zoneName, ownerName);

    Console.WriteLine ($"Assert { zoneId0 == zoneId }");
    */

    var recordType = "StationReferences";

    var location = new CLLocation (19.7303, -155.056);
    var predicate = NSPredicate.FromFormat ("distanceToLocation:fromLocation:(Position, %@) < 100", location);

    var query = new CKQuery (recordType, predicate);

    var result = await publicDatabase.PerformQueryAsync (query, zoneId);
    return result;
}

//Update
private async Task<CKRecord> UpdateInCloudKit (CKDatabase database, CKRecord record, NSString key, NSObject newValue)
{
    record [key] = newValue;
    var modifiedRecord = await database.SaveRecordAsync (record);
    return modifiedRecord;
}

//Delete 
private async Task<CKRecordID> DeleteRecord (CKDatabase database, CKRecord record)
{
    var id = record.Id;
    var deletedId = await database.DeleteRecordAsync (id);
    return deletedId;
}
    ]]></code>
      </example>
    </remarks>
  </Docs>
</Namespace>