> For the complete documentation index, see [llms.txt](https://docs.caf.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.caf.io/caf-sdk/android/standalone-modules/cafsmartauth/builder.md).

# Building the SDK

## Creating a CafSmartAuth SDK instance

In order to create a `CafSmartAuth` instance, you need to use the `CafBuilder` class. This class provides a set of methods to configure the SDK instance.

### Builder Properties

| Property      | Type    | Description                            | Required |
| ------------- | ------- | -------------------------------------- | :------: |
| `mobileToken` | String  | Mobile token provided by the platform. |     ✅    |
| `context`     | Context | Context of the application.            |     ✅    |

### Builder Methods

| Method                         | Type                         | Description                                                                              | Required |
| ------------------------------ | ---------------------------- | ---------------------------------------------------------------------------------------- | :------: |
| `setStage`                     | CafStage                     | Defines the environment stage (e.g., PROD, BETA). Default is PROD.                       |     ❌    |
| `setEmailUrl`                  | String                       | Sets the email authentication URL. Must be HTTPS protocol.                               |     ❌    |
| `setPhoneUrl`                  | String                       | Sets the phone authentication URL. Must be HTTPS protocol.                               |     ❌    |
| `setFaceAuthenticatorSettings` | CafFaceAuthenticatorSettings | Sets the face liveness authentication settings.                                          |     ❌    |
| `setThemeConfigurator`         | CafTheme                     | Sets the theme configuration for the SDK. Customize appearance for light and dark modes. |     ❌    |

### Theme Configuration

To customize the appearance of the SDK, use the theme configurator methods. Two structures are used for theme configuration: `CafThemeConfigurator` and `CafTheme`.

#### CafThemeConfigurator

```kotlin
data class CafThemeConfigurator(
    val lightTheme: CafTheme = CafTheme(),
    val darkTheme: CafTheme = CafTheme(),
)
```

This structure allows you to define separate themes for light and dark modes. Each theme is defined by a CafTheme structure.

```kotlin
data class CafTheme(
    val backgroundColor: String = "#FFFFFF",
    val textColor: String = "#FF000000",
    val linkColor: String = "#004AF7",
    val boxBorderColor: String = "#004AF7",
    val boxBackgroundColor: String = "#0A004AF7",
    val boxTextColor: String = "#004AF7",
    val progressColor: String = "#004AF7",
)
```

This structure defines various appearance attributes for the SDK. You can customize colors for backgrounds, text, links, borders, and progress indicators by providing hex string values.

### Example

```kotlin
    private fun setupCafFaceLiveness() {
        smartAuth = CafSmartAuth.CafBuilder("myMFAToken", this)
            .setStage(CafStage.PROD)
            .setEmailUrl("myEmailUrl") // Not mandatory
            .setPhoneUrl("myPhoneUrl") // Not mandatory
            .setFaceAuthenticatorSettings(
                CafFaceAuthenticatorSettings(
                    "myFaceAuthToken",
                    false,
                    true,
                    CafFilterStyle.LINE_DRAWING
                )
            )
            .setThemeConfigurator(
                CafThemeConfigurator(
                    lightTheme = CafTheme(
                        backgroundColor = "#FFFFFF",
                        textColor = "#FF000000",
                    )
                    darkTheme = CafTheme(
                        backgroundColor = "#FF000000",
                        textColor = "#FFFFFF",
                    )
                )
            )
            .build()
    }
```


---

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