Flutter – Cupertino Activity Indicator

The CupertinoActivityIndicator widget in Flutter is a part of the Cupertino widget set, which is designed to provide an iOS-like look and feel to your Flutter apps. It displays an iOS-style circular loading spinner, often used to indicate that some operation is in progress. In this article, we are going to implement the CupertinoActivityIndicator widget. A sample video is given below to get an idea about what we are going to do in this article.

Basic Syntax of CupertinoActivityIndicator Widget

CupertinoActivityIndicator(
  radius: 20.0, // Customize the size
  animating: true, // Control animation
  valueColor: AlwaysStoppedAnimation<Color>(Colors.blue), // Customize color
)

Required Tools

To build this app, you need the following items installed on your machine:

• Visual Studio Code / Android Studio
• Android Emulator / iOS Simulator / Physical Device device.
• Flutter Installed
• Flutter plugin for VS Code / Android Studio.

Step By Step Implementation

Step 1: Create a New Project in Android Studio

To set up Flutter Development on Android Studio please refer to Android Studio Setup for Flutter Development, and then create a new project in Android Studio please refer to Creating a Simple Application in Flutter.

Step 2: Import the Package

First of all import material.dart file.

import 'package:flutter/cupertino.dart';

Step 3: Execute the main Method

Here the execution of our app starts.

Dart

void main() {
  runApp(MyApp());
}

Step 4: Create CupertinoActivityIndicatorExample Class

In this class we are going to implement the CupertinoApp, here we can also set the Theme of our App. Here we call CupertinoActivityIndicatorExample class where the CupertinoActivityIndicator Widget is implemented .

Dart

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return CupertinoApp(
      debugShowCheckedModeBanner: false,
      home: CupertinoActivityIndicatorExample(),
    );
  }
}

Step 5: Create CupertinoActivityIndicatorExample Class

In this class we are going to Implement the CupertinoActivityIndicator widget that help to displays an iOS-style circular loading spinner used to indicate that some operation is in progress. Comments are added for better understanding.

Dart

class CupertinoActivityIndicatorExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      navigationBar: CupertinoNavigationBar(
        middle: Text('Cupertino Activity Indicator Example'),
      ),
      child: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            CupertinoActivityIndicator(), // This displays the activity indicator
            SizedBox(
                height: 16.0), // Adding some space below the activity indicator
            Text('Loading...'), // Text to describe the loading process
          ],
        ),
      ),
    );
  }
}

Here is the full Code of main.dart file

Dart

import 'package:flutter/cupertino.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return CupertinoApp(
      debugShowCheckedModeBanner: false,
      home: CupertinoActivityIndicatorExample(),
    );
  }
}

class CupertinoActivityIndicatorExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      navigationBar: CupertinoNavigationBar(
        middle: Text('Cupertino Activity Indicator Example'),
      ),
      child: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            CupertinoActivityIndicator(), // This displays the activity indicator
            SizedBox(
                height: 16.0), // Adding some space below the activity indicator
            Text('Loading...'), // Text to describe the loading process
          ],
        ),
      ),
    );
  }
}

Output: