Unlocking the Power of Progress Indicators in Flutter
Have you ever wondered how mobile apps communicate the status of user requests? It’s all about graphical decorators, and in Flutter, they’re called progress indicators. In this article, we’ll explore how to implement Flutter’s built-in progress indicators in asynchronous applications, and even build two apps that showcase their power.
What are Asynchronous Applications?
Asynchronous applications are composed of tasks that run independently while the rest of the program continues to execute. To determine if your app needs asynchronous execution, identify tasks that can be executed independently and those that depend on the completion of other processes.
The Role of Progress Indicators
Progress indicators help communicate the status of a user’s request, such as downloading files, uploading files, submitting forms, or loading a page. Flutter provides an abstract ProgressIndicator class, with two concrete subclasses: LinearProgressIndicator and CircularProgressIndicator.
Types of Progress Indicators
There are two types of progress indicators: determinate and indeterminate. Determinate indicators display the fraction or percentage of the task completed, while indeterminate indicators show that a task is processing without a definite duration.
Building a Determinate Progress Indicator
Let’s create an app that downloads a file from the internet and displays the progress using a circular progress indicator. We’ll use the path_provider and http dependencies to store the downloaded file and make the HTTP request.
Building an Indeterminate Progress Indicator
Next, we’ll build an app that makes an HTTP request to a GitHub Rest API and renders some of the obtained data on the screen. Since we don’t know how long the request will take, we’ll implement an indeterminate progress indicator using the flutter_spinkit package.
Choosing the Right Progress Indicator
The user experience contributed by a progress indicator is invaluable. When choosing an indicator, consider whether you can measure the task’s progress. If you can, use a determinate indicator; otherwise, opt for an indeterminate one.
Final Thoughts
Progress indicators play a crucial role in enhancing the user experience of asynchronous Flutter applications. By following this guide, you’ll be able to choose and implement the right progress indicators for your apps, ensuring that your users are always informed about the status of their requests.