To integrate Klarna Express Button as a native view in your Android application, you need to create an instance of the view, add it to your view hierarchy, and receive the user details once the Klarna Express Button flow is completed:

1. Create an instance of the button.
2. Add the button to your screen.
3. Receive the user details by implementing the event handler.

The Klarna Express Button native view in Android is called KlarnaExpressButton. You can create an instance programmatically or inflate it from an XML file. Additionally, you can also set parameters from the XML.

Create the Button Programmatically

You can create the native view programmatically and place it in your application with desired layout options.

//Create an instance of KlarnaExpressButton
val button = KlarnaExpressButton(...)

// Add it to your container with desired layout parameters
val layoutParams = ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT)
containerViewGroup.addView(button, 0, layoutParams)

Create the Button from XML

Optionally you can also create the native view in your XML and get the view instance programmatically either by findViewById or by the generated DataBinding instance of your layout.

<com.klarna.mobile.sdk.api.expressbutton.KlarnaExpressButton
      android:id="@+id/klarnaExpressButton"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      …
/>

Parameters used for the Klarna Express Button are set as variables of the button instance or as attributes in the XML declaration.

While the user is interacting with the Klarna Express Button or when the flow is completed, you can receive events accordingly by setting an event handler when creating an instance of the button.

val eventHandler = object : KlarnaEventHandler {
   override fun onEvent(klarnaComponent: KlarnaComponent, event: KlarnaProductEvent) {
      when(event.action) {
         KlarnaExpressButtonEvent.USER_TAPPED_BUTTON -> {
            // User tapped the Klarna Express Button
         }
         KlarnaExpressButtonEvent.USER_AUTHENTICATED -> {
            // User is authenticated. You can read the user details      
            // in event.params attribute.

Klarna Express Button events are as follows:

Predefined Klarna Express Button error names are as follows:

Example of user details received with USER_AUTHENTICATED event (event.params value):

{
  first_name: "John",   
  last_name: "Doe",
  email: "example@example.com",
  date_of_birth: "1990-01-01",
  phone: "+18004444444",
  address: {
    street_address: "3100 Pear Road",
    street_address2: null,
    postal_code: "93309",

Example of user’s data token received with USER_AUTHENTICATED_DATA_TOKEN event (event.params value):

{
   express_button_data_token: "1886db92-tj82-1277-n6h2-1197be8701c6"
}

Klarna offers several theme, label, and shape options to customize the Klarna Express Button's appearance to match the look and feel of your application.

KlarnaButtonTheme

KlarnaButtonTheme enumeration will be used to define which style to be used, depending on either the app’s configuration or the system setting.

Name	Description	Express Button
KLARNA	Renders the button in the Klarna pink theme. This is the recommended theme as it has the highest brand recognition and the likelihood of usage by your customers.
LIGHT	Renders the button in white. It is recommended to use this theme on dark backgrounds.
DARK	Renders the button in black. It is recommended to use this theme on light backgrounds.
AUTO	Automatic theme (light or dark) that will use the system’s user interface style.

KlarnaButtonShape

In order for the Klarna Express Button to fit into the aesthetic of your application, we offer different button shapes.

Name	Description	Express Button
ROUNDED_RECT	Renders the button as a rectangle with rounded corners.
PILL	Renders the button as a pill-shaped button.
RECTANGLE	Renders the button as a rectangle with square corners.

KlarnaButtonLabel

KlarnaButtonLabel enumeration will be used to select which label you wish to be shown on the button.

Name	Description	Express Button
KLARNA_PRODUCT	Renders the button with this product’s specific label which is “Klarna. Express Checkout”.
KLARNA	Renders the button only with Klarna logo.