Xamarin iOS Applications

11 Xamarin iOS Applications

If you use the Xamarin platform to develop iOS apps, you can use the SDK that Oracle Mobile Cloud Service (MCS) provides for Xamarin iOS apps. This SDK simplifies authentication with MCS and provides native wrapper classes for MCS platform APIs.

Getting the SDK for Xamarin iOS

To get the MCS client SDK for Xamarin iOS, go to the Oracle Technology Network’s MCS download page.

To use this SDK, you should have the following software on your system:

Microsoft Visual Studio, with support for Xamarin development.
Xcode 9.1 or later and iphoneos 11.0.

See http://www.oracle.com/technetwork/java/javase/downloads/index.html for JDK downloads.

Adding the SDK to a Xamarin iOS Project

If you haven’t already done so, extract the contents from the SDK zip.
In Visual Studio, create a Visual C# iOS app.
Add the SDK's DLL file to your app by right-clicking the project's References node and selecting Edit References, clicking the .NET Assembly tab, and then browsing to the IOS.dll file in the extracted SDK zip.
Add the configuration file to the app by right-clicking the project's root node and selecting Add > Add Files and then navigating to the SDK's OMC.plist file.
Select the node for OMC.plist so that it's properties are displayed in the Properties pane. Then make sure that the Build Action property is set to BundleResource.
Add the SynchStore.momd folder to the app by right-clicking the project's root node and selecting Add > Add Existing Folder and then navigating to the SDK's SynchStore folder.
For all of the files in the SynchStore.momd folder, make sure that the Build Action property is set to BundleResource.
Open OMC.plist and fill in the environment details for the mobile backend that the app will be using. See Configuring SDK Properties for Xamarin iOS.

Configuring SDK Properties for Xamarin iOS

To use the SDK in a Xamarin iOS project, you need to add the OMC.plist configuration file to the app and fill it in with environment details for your mobile backend. In turn, the SDK classes use this information to access the mobile backend and construct HTTP headers for REST calls made to APIs.

You package the configuration file in the root of your app’s main bundle.

Here’s an example of the contents of the OMC.plist file. Pay careful attention to the hierarchy of elements.

Description of omcplist_screenshot.png follows

Description of the illustration omcplist_screenshot.png

Here’s the source code for the same example:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"
<plist version="1.0">
<dict>
  <key>mobileBackends</key>
  <dict>
    <key>FixItFast_Customer</key>
    <dict>
      <key>default</key>
      <true/>
      <key>baseURL</key>
      <string>https://fif.cloud.oracle.com</string>
      <key>appKey</key>
      <string>ebfbc8ea-9173-442b-8a5e-2fae63c64422</string>
      <key>authorization</key>
      <dict>
        <key>authenticationType</key>
        <string>OAuth</string>
        <key>OAuth</key>
        <dict>
          <key>tokenEndpoint</key>
          <string>https://oam.oracle.com/oam/oauth2/tokens</string>
          <key>clientID</key>
          <string>ddb7ff5a-0d86-4b4a-8164-ddad03734249</string>
          <key>clientSecret</key>
          <string>pFmzazXzNTBNVDyraQs7</string>
        </dict>
      </dict>
    </dict>
  </dict>
  <key>logLevel</key>
  <string>debug</string>
</dict>
</plist>

Here are the key entries in the OMC.plist file. You can obtain the necessary environment details from the Settings and Clients pages of the mobile backend.

mobileBackends — a dictionary entry containing a nested dictionary for your mobile backend such as FixItFast_Customer. (When you call OMCMobileBackend in an app, you need to supply the value of that entry as a parameter to OMCMobileBackendManager.) That entry, in turn, contains entries for appKey, baseURL, authenticationType, mobileBackendID, anonymousKey, and, optionally, networkConnectionTimeout. See the example below.
baseURL — The URL your application uses to connect to its mobile backend.
appKey — The application key, which is a unique string assigned to your app when you register it as a client in MCS. See Registering an App as a Client in MCS. If you have not registered the app as a client in MCS, assign a placeholder value for this entry.
authorization — Use this key to define the type of authentication the app will be using and specify the required credentials. The contents of the authorization key depend on the type of authentication.
- authenticationType — Defines the type of authentication mechanism being used in your mobile application. Possible values are OAuth (for OAuth Consumer), basic (for HTTP Basic), SSO, SSOTokenExchange and Facebook. Include a dictionary for each supported authentication type with the required credentials as explained in the sections that follow.
networkConnectionTimeout — (Optional) The network timeout for API calls, in seconds. Should you need to do any network performance tuning, you can add this property, though you should use it with care. Keep in mind that app responsiveness issues might be better addressed in the app design itself. The default timeout is 60 seconds.
logLevel — Determines how much SDK logging is displayed in the app’s console. The default value is error. Other possible values (in increasing level of detail) are warning, info, and debug. It is also possible to set the value to none.
logHTTPRequestBody — When set to true, the SDK will also log the HTTP and HTTPS headers and body in the requests to MCS.
logHTTPResponseBody — When set to true, the SDK will also log the HTTP and HTTPS headers and body in responses from MCS.
offlineAuthenticationEnabled — If set to true, offline login will be allowed.

The contents and sub-elements of the authorization dictionary depend on what kind of authentication the app will be using.

OAuth Consumer

For OAuth, set the value of the authenticationType property to OAuth and fill in the OAuth credentials provided by the mobile backend.

tokenEndpoint — The URL of the OAuth server your application goes to, to get its authentication token.
clientID — The unique client identifier assigned to all applications when they’re first created in your mobile backend.
clientSecret — The unique secret string assigned to all applications when they’re first created in your mobile backend.