GraphQL is a powerful query language for APIs that allows clients to request data from a server in a single request. By using GraphQL in your Flutter app, you can easily retrieve data from your backend and use it to create a dynamic and interactive user experience. In this article, we’ll walk through the process of setting up GraphQL in a Flutter project and making API calls.

![flutter graphql](https:&#x2F;&#x2F;devbrite.io&#x2F;media&#x2F;cover15.jpg)
## Prerequisites

Before you get started, you’ll need the following:

* A Flutter project.
* An API that supports GraphQL.
* A GraphQL client library.

## Creating a Flutter Project

If you don’t already have a Flutter project, you can create one with the following command:

&#96;&#96;&#96;
$ flutter create my_project
&#96;&#96;&#96;

## Installing GraphQL into Your Project

To add GraphQL to your project, you’ll need to install the &#96;graphql_flutter&#96; package. You can do this from your project’s &#96;pubspec.yaml&#96; file:

&#96;&#96;&#96;yaml
dependencies:
  graphql_flutter: ^3.0.0
&#96;&#96;&#96;

## Integrating GraphQL Client in Flutter

Once the package is installed, you’ll need to create a GraphQL client. You can do this by creating a &#96;GraphQLClient&#96; object and passing it your GraphQL API’s URL:

&#96;&#96;&#96;dart
final HttpLink httpLink = HttpLink(
  uri: &#x27;https:&#x2F;&#x2F;your-graphql-server.com&#x2F;graphql&#x27;,
);

final ValueNotifier&lt;GraphQLClient&gt; client = ValueNotifier(
  GraphQLClient(
    link: httpLink,
    cache: InMemoryCache(),
  ),
);
&#96;&#96;&#96;

## Creating a GraphQL Query in Flutter

Once the client is set up, you can start making GraphQL queries. To do this, you’ll need to define the query in your project’s &#96;queries.dart&#96; file. For example, the following query retrieves the user’s name and email address:

&#96;&#96;&#96;dart
const String getUserQuery = r&#x27;&#x27;&#x27;
  query getUser($id: ID!) {
    user(id: $id) {
      name
      email
    }
  }
&#x27;&#x27;&#x27;;
&#96;&#96;&#96;

## Making a GraphQL API Call in Flutter

Once the query is defined, you can make an API call by using the &#96;GraphQLClient&#96; object. Here’s an example of how you could use the &#96;getUserQuery&#96; query to make an API call:

&#96;&#96;&#96;dart
final QueryResult result = await client.query(
  QueryOptions(
    documentNode: gql(getUserQuery),
    variables: {
      &#x27;id&#x27;: &#x27;12345&#x27;
    }
  )
);
&#96;&#96;&#96;

## Creating a GraphQL Mutation in Flutter

You can also use GraphQL to make mutations, which allow you to create, update, or delete data on the server. To do this, you’ll need to define the mutation in your project’s &#96;mutations.dart&#96; file. For example, the following mutation creates a new user:

&#96;&#96;&#96;dart
const String createUserMutation = r&#x27;&#x27;&#x27;
  mutation createUser($name: String!, $email: String!) {
    createUser(name: $name, email: $email) {
      id
      name
      email
    }
  }
&#x27;&#x27;&#x27;;
&#96;&#96;&#96;

To make the mutation, you can use the &#96;GraphQLClient&#96; object, just like you did for the query. Here’s an example of how you could use the &#96;createUserMutation&#96; mutation to make a mutation call:

&#96;&#96;&#96;dart
final MutationOptions options = MutationOptions(
  documentNode: gql(createUserMutation),
  variables: {
    &#x27;name&#x27;: &#x27;John Doe&#x27;,
    &#x27;email&#x27;: &#x27;john@example.com&#x27;,
  },
);

final QueryResult result = await client.mutate(options);
&#96;&#96;&#96;

## Conclusion

Using GraphQL in your Flutter app can make it easier to retrieve data from your backend and create a dynamic user experience. In this article, we’ve covered how to set up GraphQL in a Flutter project, create GraphQL queries and mutations, and make API calls. With this knowledge, you’ll be able to create powerful and interactive apps with GraphQL.

How to Use GraphQL in Flutter

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