How to Build Responsive Applications With Flutter

Configuration changes are common for apps. The keyboard appears when the phone is rotated vertically or horizontally. Foldable smartphones, multi-window features for Android, and Catalyst have uncovered an unlimited number of screen sizes.

For your app to look polished, it must "react" appropriately to configuration changes. Flutter developers often have trouble with responsive design. Let's learn how to make a responsive Flutter app in this blog.

To begin with,

What is Responsive Design?

A responsive design allows a website or application to 'adapt' to different screen sizes without affecting function or usability. An application that is responsive to the device makes browsing more enjoyable for the user.

Responsive design implies using the same code to adapt to different screens and layouts depending on the device, whether that is a smartphone, tablet, laptop, or computer. Using it, developers can write a single HTML, CSS, and Javascript code for multiple devices and browsers.

Responsive design can be challenging, but making an app responsive can prove far more beneficial in the long run.

Responsive Design Goals:

Wider audience 

Flexible and responsive apps will attract more audiences.

Improved SEO

Flexible and responsive web design enhances search engine optimization. 

Improved browsing experience

Web app designs that are responsive and flexible improve browsing experiences and even increase sales. 

Brand visibility

A fast and beautiful app design improves brand visibility.

Why is using responsive design in Flutter a must?

Flutter applications run on mobile devices, tablets, and desktops/laptops. Apps must be responsive to all the different screen sizes and resolutions of today's mobile devices. Users can rotate their phones, and applications should adjust when viewed in landscape or portrait modes. Providing a seamless user experience requires apps to be responsive enough to meet so many user requirements.

We'll look at how iOS and Android natively handle layouts for different screen sizes.

iOS Approach

iOS's main concepts for defining responsive layouts are:

1. Auto layout

By using auto layout constraints, views can be dynamically positioned and sized based on various size classes. Constraints eliminate the need to manually update frames and positions. Views are automatically resized when the size changes.

2. Size classes

It is easy to create layouts that work on iPads and iPhones of all sizes and orientations when we use size classes.

3. UI Elements

Some of the UI elements on iOS assist in building responsive UI, such as UI View Controller and UI Split View Controller.

Android Approach

Android's main concepts for defining responsive layouts are:

• Constraint layout

With constraint layout, we can design an entire UI with drag-and-drop capabilities, enhance its performance, manage widgets through a single line of code, and add animations to the UI elements easily. With large or very few screens, a constraint layout does not solve the problem.

• Alternative layouts

In Android Studio, you can use alternative layouts to resolve the aforementioned issue. The layout files will be switched automatically depending on the device's screen size if you define separate layout files for various screen sizes.

• Fragments

Multi-pane layouts for big screens can be designed by separating the UI logic into distinct components instead of defining the logic separately.

• Vector graphics

Android Studio's Vector Asset Studio makes it easy to create vector graphics for multiple Android screens.

Responsive Design in Flutter

While designers love magic, the execution process in the real world is not as easy as they would like. Flutter will make your designers forget the phrase "it's impossible".  

Flutter provides many widgets and classes to help designers implement responsive UI ideas. Developers can decide how to implement them in their applications. Here are a few examples:

• MediaQuery 

• MediaQueryData 

• OrientationBuilder

• LayoutBuilder 

• AspectRatio

• CustomSingle

• ChildLayout

• CustomMultiChildLayout 

• FittedBox 

• FractionallySizedBox 

Keyboard changes processing

Almost all apps include text fields, and when a user interacts with an app, a keyboard appears. Scaffold widgets automatically process keyboard changes, thereby solving linking issues. MediaQueryData.viewInsets is controlled by a resizeToAvoidBottomInset field.

Using MediaQuery to define configuration

Using MediaQuery, you can find out the size of the window in real-time. The app's size and orientation are suggested. If you want to make decisions based on the context rather than just the widget's size, the MediaQuery widget is useful.

Use the LayoutBuilder Class

LayoutBuilder is a simplified version of MediaQuery, created to deal with basic size requests. Using this widget, you can understand how much space you have for the widget and build child components based on it.

You get a BoxConstraints object from its builder property. Depending on the constraint's properties (the device's height, width, aspect ratio, or some other property), you can adjust the display. If max Width exceeds your width breakpoint, return a scaffold object with a row with a list on the left. Return a Scaffold object with a drawer containing the list if it's narrower. The build function runs when the constraints change.

Use the OrientationBuilder Class

LayoutBuilder and OrientationBuilder are pretty similar widgets. The Orientation object can be obtained from its builder property. Example: use OrientationBuilder to change the number of columns of GridView.

Use the FittedBox Class

Depending on the parent widget size, you must often scale the text. For various platforms, you can either use fixed values or let the widget scale according to its parent widget.

As a result, the text is resized. Other types of BoxFit can also be used.

Use the AspectRatio Widget

You can ignore the size of an app, but you must consider the aspect ratio. No matter what the device's size is, it can be wide, thin, or square. At this point, Flutter helps you by providing the AspectRatio widget, which sizes the child value to a specific aspect ratio.

Use FractionallySizedBox Widgets

There are times when your design requires relative dimensions, for example, a button occupies 80% of the app's width but a margin takes up only 10%. This can be handled by FractionallySizedBox.

You can resize a child by wrapping it in a FractionallySizedBox. Using alignment you can control where exactly the fractionally sized widget is supposed to appear (0.8 means 80% of the available size). For fractionally sized whitespace, you can also use FractionallySizedBox without a child.

This FractionallySizedBox will probably be best wrapped in a flexible widget so it can play well with rows and columns.

CustomMultiChildLayout

The CustomMultiChildLayout widget is designed for advanced users of Flutter responsive design.

Conclusion

The design must be user-friendly and responsive no matter what device is being used. Websites that don't accommodate mobile users are becoming extinct. Websites with responsive designs load quickly and without distortion, resulting in a better online and offline browsing experience.

Companies can benefit from responsive applications by lowering development and maintenance costs, increasing search ranking, and simplifying application monitoring.

HashStudioz, the best Flutter app development company builds and deploys apps for iOS and Android devices through its excellent Flutter mobile app development services.