> For the complete documentation index, see [llms.txt](https://docs.wepin.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wepin.io/en/widget-integration/flutter-sdk/widget/initialization.md).

# Initialization

After installing the Wepin Flutter Widget SDK, the next step is to initialize the SDK. SDK initialization involves creating an instance of `WepinWidgetSDK` and using the `init()` function to proceed.

## **Import SDK**

To use the Wepin Flutter Widget SDK, you first need to import the SDK. Add the following import statements:

```dart
import 'package:wepin_flutter_widget_sdk/wepin_flutter_widget_sdk.dart';
import 'package:wepin_flutter_widget_sdk/wepin_flutter_widget_sdk_type.dart';
```

## **Creating the WepinWidgetSDK Instance**

Before creating an instance of `WepinWidgetSDK`, you must register your app's Android/iOS information in the Wepin Workspace.

{% content-ref url="/pages/jbQ0WaKQeMfxsY4nDVeP" %}
[App Registration](/en/archive/getstarted/registration.md)
{% endcontent-ref %}

Using the registered app information, create an instance of `WepinWidgetSDK`. In the `state init` stage of the `main.dart` file, create and initialize the `WepinWidgetSDK` instance as follows:

{% code title="main.dart" %}

```dart
WepinWidgetSDK wepinSDK = WepinWidgetSDK(
    wepinAppKey: wepinAppKey, 
    wepinAppId: wepinAppId
);
```

{% endcode %}

## **SDK Initialization (init)**

When initializing the Wepin Flutter Widget SDK, you can define the required widget properties.

```dart
await wepinSDK.init({WidgetAttributes? attributes});
```

#### **Parameters**

* **attributes** `<WidgetAttributes>`***optional*** -  Widget properties to define during initialization.
  * **defaultLanguage** `<String>`: \
    Set the default language of the widget. The default value is `ko`, and currently supported languages are `en`, `ja` and `ko`.
  * **defaultCurrency** `<String>`\
    Set the default currency of the widget. The default value is `KRW`, and currently supported currencies are `USD`, `JPY`and `KRW`.

#### **Return Value**

* **Future\<void>**

#### **Example**

```dart
await wepinSDK.init(WidgetAttributes(
    defaultLanguage: 'ko',
    defaultCurrency: 'KRW',
));
```

## **Checking Initialization Status (isInitialized)**

You can check whether the WepinSDK has been successfully initialized.

```dart
bool isInitialized = wepinSDK.isInitialized();
```

#### **Parameters**

* **None**

#### **Return Value**

* **\<bool>**\
  Returns `true` if the initialization was successful, and `false` if it failed.

#### **Example**

```dart
await wepinSDK.init(WidgetAttributes(
    defaultLanguage: 'ko',
    defaultCurrency: 'KRW',
));

if (wepinSDK.isInitialized()) {
  print('WepinSDK is initialized!');
}
```

## **Changing Language and Currency (changeLanguage)**

You can change the language and currency of the widget.

```dart
wepinSDK.changeLanguage({String language, String currency});
```

#### **Parameters**

* **language** `<String>`\
  Specifies the language to be displayed in the widget. Currently supported languages are `en,` `ja` and `ko`.
* **currency** `<String>`\
  Specifies the currency to be displayed in the widget. Currently supported currencies are `USD`, `JPY` and `KRW`.

#### **Example**

```dart
wepinSDK.changeLanguage(
  language: 'ko',
  currency: 'KRW'
);
```