Omnis App Framework


Omnis Software Ltd

September 2019



User Guide

Setup – Android

Instructions for setting-up the Omnis App Framework on Android devices.


Support Library

The Omnis Interface uses the AndroidX support library. At time of publication, this is a relatively new replacement to the previous Support Library used by Android apps, so you may need to migrate existing code to AndroidX.

If you are creating a new project, there is currently a checkbox shown in the New Project wizard - "Use androidx.* artifacts" - make sure to enable this.

Add The Library To Your Project

// Dependencies required by OmnisInterface (as we're not pulling it in from a repository):
implementation omnisInterfaceImplementationDependencies.values()
implementation omnisInterfaceAPIDependencies.values()

And add the following to the top of that file:

apply from: "../omnisInterface/omnisinterface_dependencies.gradle"

Add the omnisInterface module as a module dependency of your app (again accessed via the module settings window):

Instantiate The Omnis Interface


private lateinit var mOmnisInterface: OmnisInterface
override fun onStart() {
  if (!this::mOmnisInterface.isInitialized) {
    val webContainer = findViewById<OMWebContainer>(
    mOmnisInterface = OmnisInterface(webContainer, this)


 Setup - iOS

Instructions for setting-up the Omnis App Framework on iOS devices.

Add the Framework

Add the framework to your project’s Embedded Binaries:

Create a UIView, and set its Class to OMWebContainer - this view will become the container which hosts the webview to run your Remote Forms etc.


class ViewController: UIViewController {
  var omnisInterface: OmnisInterface!
@IBOutlet weak var webviewContainer: OMWebContainer!
  override func viewDidLoad() {
    omnisInterface = OmnisInterface(webviewContainer: webviewContainer, viewController: self)

Stripping The Framework

The OmnisInterface Framework is provided as a Fat Universal binary, which contains slices for both device & simulator architectures.

To keep the size of you built app down, and to allow your app to be submitted to the App Store, you should strip unused architectures (i.e. Simulator architectures from device builds).

You can do this by:

# Uncomment below to log output:
#exec > /tmp/${PROJECT_NAME}_striparchs.log 2>&1
# This script loops through the frameworks embedded in the application and
# removes unused architectures.
# Thanks to:
find "$APP_PATH" -name '*.framework' -type d | while read -r FRAMEWORK
  FRAMEWORK_EXECUTABLE_NAME=$(defaults read "$FRAMEWORK/Info.plist" CFBundleExecutable)
  echo "Executable is $FRAMEWORK_EXECUTABLE_PATH"
  for ARCH in $ARCHS
  echo "Merging extracted architectures: ${ARCHS}"
  lipo -o "$FRAMEWORK_EXECUTABLE_PATH-merged" -create "${EXTRACTED_ARCHS[@]}"
  rm "${EXTRACTED_ARCHS[@]}"
  echo "Replacing original executable with thinned version"

Loading Forms

Once you have set up your OmnisInterface, you can call methods on it (or the objects it exposes as properties - such as scafHandler) to interact with the JS Client.

To load a form, simply call OmnisInterface's loadURL method, giving it the full URL to your Remote Form's .htm file.

Android Example

val theUrl = URL("")

iOS Example

let theUrl = URL(string: "")
self.omnisInterface.loadURL(url: theUrl!)

Loading Progress Events

In order to be notified when a form begins/ends loading etc, you need to assign a class which implements theOMWebNavigationDelegate protocol to your OmnisInterface's webNavigationDelegate property.

The delegate methods will then be called at the appropriate times.

Offline Forms

You must initialise your OmnisInterface's scafHandler by calling initScafController, in order to enable support for offline forms.

This sets the ScafHandler up with details of your Omnis server, and offline form details etc.

Once this has been done, and SCAFs have been updated/extracted*, you can load the configured offline form by calling:


* Note that this is an asynchronous process, so you need some way of determining when the offline form is ready:

Implement Delegate

You need to assign some class, which implements the OMScafHandlerDelegate to the scafHandler's delegate property.

The delegate's onOfflineModeConfigured method will then be called when your offline form is ready (either after startup, once everything is prepared, or after you call updateScafs).

Custom Messaging - iOS

To implement custom messaging between the JS Client and your app:

Omnis to iOS

omnis_form.prototype.sendWrapperMessage = function(id, data, formCallbackMethod)
if (formCallbackMethod)
  var callbackString = 'var form = jOmnis.getOmnisForm(jOmnis.instIndexFromIdent(' + this.ident +
    '), jOmnis.formIndexFromIdent(' + this.ident + '));' +
    '[], 0, 0, "' + formCallbackMethod + '");' + // Insert the method name as the first argument
    'return form ? form.callMethod.apply(form, arguments) : null;';
  callbackString = "";
sendDeviceRequest(id, callbackString, data);


JavaScript: _form.sendWrapperMessage("myMessage"{firstName: "Alan", lastName: "Alphabet"}"$messageReturn");

iOS to Omnis

Or, in order to call a callback function passed to the wrapper from sendWrapperMessage above, you can use your OmnisInterface's callJSFunctionText method, passing it the value given in messageFromJSClient's retID member as the functionText.


extension MainViewController: OMCommsDelegate
  func messageFromJSClient(data: [String : AnyObject]?) -> Bool! {
  if let id = data?["ID"] as? String
   switch id
        case "myMessage":
        let firstName = data?["Data"]?["firstName"] as? String ?? ""
        let lastName = data?["Data"]?["lastName"] as? String ?? ""
        // TODO: Something with the data
        // Call back to an Omnis method, if one was provided:
        if let returnFunc = data?["retID"] as? String
          omnisInterface.callJSFunctionText(returnFunc, params: [
            "'\(id)'", // Will be first param passed to method
            "'\(firstName)'", // Will be 2nd param passed to method
            "'\(lastName)'" // Will be 3rd param passed to method
            ], completionHandler: nil)
          return false; // Let default handling occur for messages we're not explicitly handling.
    print("No ID provided!")
    return false // Let default handling occur

If you followed the examples above, after sending the message to the wrapper, the form's $messageReturn method will be called, with the following parameters:

  p1: "myMessage" (The message ID)

  p2: "Alan"

  p3: "Alphabet"

Photo Functionality - Android

In order for the photo functionality to work with your app, you must create a File Provider, which allows sharing of files within your app's internal storage area (So the Camera app can save files there).

1) Create a resource file to define the File Provider:

Create an xml resource with content to provision a folder within the "files-path" area as shareable.

Example - fileprovider.xml

<?xml version="1.0" encoding="utf-8"?>
  <files-path name="photos" path="photos" />

By default, it should have a path named "photos".

2) Include the File Provider in your Manifest

Edit your AndroidManifest.xml file, and add the File Provider to the Application section:


    android:resource="@xml/fileprovider" />

Set the android:authorities attribute to your own domain identifier.

3) Override File Provider defaults if necessary

The OMImages class has the following public static members, which should be overridden with your own values if they differ from the defaults:

FILE_PROVIDER_AUTHORITY: Should match your android:authorities above (default = "net.omnis.fileprovider").

FILE_PROVIDER_PATH: Should be the path specified for your files-path entry in fileprovider.xml (default= "photos").

Barcode Functionality - Android

Barcode functionality on Android makes use of Google's ML Kit framework, and as such requires a Firebase project.

You need to create a project in Firebase, then download the Google-Services.json file for your project, and add to the root of your App module in your Android Studio project.