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Introduction
In this part, we'll look at using the REST API in a Flutter application. The majority of apps nowadays use APIs to access external data. As a result, this section will be crucial for developers who want to create a career in Flutter. So let's start with the topic.
Flutter REST API
To use HTTP resources, Flutter offers the HTTP package. The HTTP package employs await and async capabilities and provides several high-level methods for sending and receiving data from distant places, including read, get, post, put, head, and delete. These techniques make it easier to create REST-based mobile apps.
Methods of Flutter API
The following is a detailed explanation of the HTTP package's basic methods:
Read: This method is used to read or retrieve a resource's representation. It uses the get function to request the supplied URL and returns the response as a Future<String>.
Get: This function uses the get method to fetch the supplied URL and produces a Futureresponse> as a response. In this case, the answer is a class containing the response data.
Post: This method is used to submit the data to the specified resources. It requests the specified URL by posting the given data and returns a response as Future<response>.
Put: This procedure is used to update the system's capabilities. It incorporates the request payloads into all existing representations of the target resource. This function requests the supplied URL and returns a Future response. <response>.
Head: It is the same as the Get method but without a response body.
Delete: This method is used to remove all the specified resources.
How to Fetch the data from the internet
Add the HTTP package
The HTTP package is the most straightforward way to retrieve data from the internet.
Add the HTTP package to the pubspec.yaml file's requirements section to install it. The current version of the HTTP package may be found at the pub.dev.
Make a network request
This will explain how to use the http.get() function to acquire a sample album from a JSONPlaceholder.
The function http.get() produces a Future containing a Response.
Future is a fundamental Dart class that allows you to interact with async activities. A Future object denotes a prospective value or error that will be accessible later.
The data obtained from a successful http call is stored in the http.Response class.
Fetch the data
In either the initState() or didChangeDependencies() methods, use the fetchAlbum() function.
The initState() function is only called once and is never invoked again. Put the call inside the didChangeDependencies() function if you wish to have the option of refreshing the API in response to an InheritedWidget updating.
Display the data
Use the FutureBuilder widget to display the data on the screen. Flutter includes the FutureBuilder widget, which simplifies working with asynchronous data sources.
There are two criteria that you must provide:
You wish to collaborate with the Future. The Future is returned by the fetchAlbum() method in this situation.
Depending on the state of the Future: loading, success, or error, this function Object() { [native code] } function informs Flutter what to render.
Frequently Asked Questions
How to create an API in Flutter?
The first and most fundamental step in creating a new flutter application. Open your project's pubspec.yaml file and add the requirements you need to add.
What is HTTP in Flutter?
The http package in Flutter allows you to consume HTTP resources. http is a Future-based library with capabilities like await and async. It includes several high-level techniques that make developing REST-based mobile apps more accessible.
How to test the integration of the client with the REST API?
We must validate the following to evaluate our client's integration with the Rest API: Endpoint, verb, headers, and content, if appropriate, are all correctly provided to the API. The server answers are successfully parsed. Error answers from the server are handled appropriately.
Conclusion
In this article, we have exhaustively explained the Flutter REST API integration topic.
We have explained the topic, the methods used in the Flutter API, and how to fetch the data from the internet.
If you want to know more about Flutter, visit here.
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